Code re-work: shadow mapping.

includes/learnopengl/shader.h

@@ -106,40 +106,40 @@ public:
     }
     // utility uniform functions
     // ------------------------------------------------------------------------
-    void setBool(std::string name, bool value) 
+    void setBool(std::string name, bool value) const
     {         
         glUniform1i(glGetUniformLocation(ID, name.c_str()), (int)value); 
     }
     // ------------------------------------------------------------------------
-    void setInt(std::string name, int value) 
+    void setInt(std::string name, int value) const
     { 
         glUniform1i(glGetUniformLocation(ID, name.c_str()), value); 
     }
     // ------------------------------------------------------------------------
-    void setFloat(std::string name, float value) 
+    void setFloat(std::string name, float value) const
     { 
         glUniform1f(glGetUniformLocation(ID, name.c_str()), value); 
     }
     // ------------------------------------------------------------------------
-    void setVec2(std::string name, const glm::vec2 &value)  
+    void setVec2(std::string name, const glm::vec2 &value) const
     { 
         glUniform2fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]); 
     }
-    void setVec2(std::string name, float x, float y) 
+    void setVec2(std::string name, float x, float y) const
     { 
         glUniform2f(glGetUniformLocation(ID, name.c_str()), x, y); 
     }
     // ------------------------------------------------------------------------
-    void setVec3(std::string name, const glm::vec3 &value)    
+    void setVec3(std::string name, const glm::vec3 &value) const
     { 
         glUniform3fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]); 
     }
-    void setVec3(std::string name, float x, float y, float z) 
+    void setVec3(std::string name, float x, float y, float z) const
     { 
         glUniform3f(glGetUniformLocation(ID, name.c_str()), x, y, z); 
     }
     // ------------------------------------------------------------------------
-    void setVec4(std::string name, const glm::vec4 &value)             
+    void setVec4(std::string name, const glm::vec4 &value) const
     { 
         glUniform4fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]); 
     }
@@ -148,17 +148,17 @@ public:
         glUniform4f(glGetUniformLocation(ID, name.c_str()), x, y, z, w); 
     }
     // ------------------------------------------------------------------------
-    void setMat2(std::string name, const glm::mat2 &mat)
+    void setMat2(std::string name, const glm::mat2 &mat) const
     {
         glUniformMatrix2fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, &mat[0][0]);
     }
     // ------------------------------------------------------------------------
-    void setMat3(std::string name, const glm::mat3 &mat)
+    void setMat3(std::string name, const glm::mat3 &mat) const
     {
         glUniformMatrix3fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, &mat[0][0]);
     }
     // ------------------------------------------------------------------------
-    void setMat4(std::string name, const glm::mat4 &mat)
+    void setMat4(std::string name, const glm::mat4 &mat) const
     {
         glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, &mat[0][0]);
     }

includes/learnopengl/shader_m.h

@@ -74,65 +74,65 @@ public:
     }
     // activate the shader
     // ------------------------------------------------------------------------
-    void use() 
+    void use() const
     { 
         glUseProgram(ID); 
     }
     // utility uniform functions
     // ------------------------------------------------------------------------
-    void setBool(std::string name, bool value) 
+    void setBool(std::string name, bool value) const
     {         
         glUniform1i(glGetUniformLocation(ID, name.c_str()), (int)value); 
     }
     // ------------------------------------------------------------------------
-    void setInt(std::string name, int value) 
+    void setInt(std::string name, int value) const
     { 
         glUniform1i(glGetUniformLocation(ID, name.c_str()), value); 
     }
     // ------------------------------------------------------------------------
-    void setFloat(std::string name, float value) 
+    void setFloat(std::string name, float value) const
     { 
         glUniform1f(glGetUniformLocation(ID, name.c_str()), value); 
     }
     // ------------------------------------------------------------------------
-    void setVec2(std::string name, const glm::vec2 &value)  
+    void setVec2(std::string name, const glm::vec2 &value) const
     { 
         glUniform2fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]); 
     }
-    void setVec2(std::string name, float x, float y) 
+    void setVec2(std::string name, float x, float y) const
     { 
         glUniform2f(glGetUniformLocation(ID, name.c_str()), x, y); 
     }
     // ------------------------------------------------------------------------
-    void setVec3(std::string name, const glm::vec3 &value)    
+    void setVec3(std::string name, const glm::vec3 &value) const
     { 
         glUniform3fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]); 
     }
-    void setVec3(std::string name, float x, float y, float z) 
+    void setVec3(std::string name, float x, float y, float z) const
     { 
         glUniform3f(glGetUniformLocation(ID, name.c_str()), x, y, z); 
     }
     // ------------------------------------------------------------------------
-    void setVec4(std::string name, const glm::vec4 &value)             
+    void setVec4(std::string name, const glm::vec4 &value) const
     { 
         glUniform4fv(glGetUniformLocation(ID, name.c_str()), 1, &value[0]); 
     }
-    void setVec4(std::string name, float x, float y, float z, float w) 
+    void setVec4(std::string name, float x, float y, float z, float w) const
     { 
         glUniform4f(glGetUniformLocation(ID, name.c_str()), x, y, z, w); 
     }
     // ------------------------------------------------------------------------
-    void setMat2(std::string name, const glm::mat2 &mat)
+    void setMat2(std::string name, const glm::mat2 &mat) const
     {
         glUniformMatrix2fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, &mat[0][0]);
     }
     // ------------------------------------------------------------------------
-    void setMat3(std::string name, const glm::mat3 &mat)
+    void setMat3(std::string name, const glm::mat3 &mat) const
     {
         glUniformMatrix3fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, &mat[0][0]);
     }
     // ------------------------------------------------------------------------
-    void setMat4(std::string name, const glm::mat4 &mat)
+    void setMat4(std::string name, const glm::mat4 &mat) const
     {
         glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE, &mat[0][0]);
     }

includes/learnopengl/shader_s.h

@@ -78,17 +78,17 @@ public:
     }
     // utility uniform functions
     // ------------------------------------------------------------------------
-    void setBool(std::string name, bool value) 
+    void setBool(std::string name, bool value) const
     {         
         glUniform1i(glGetUniformLocation(ID, name.c_str()), (int)value); 
     }
     // ------------------------------------------------------------------------
-    void setInt(std::string name, int value) 
+    void setInt(std::string name, int value) const
     { 
         glUniform1i(glGetUniformLocation(ID, name.c_str()), value); 
     }
     // ------------------------------------------------------------------------
-    void setFloat(std::string name, float value) 
+    void setFloat(std::string name, float value) const
     { 
         glUniform1f(glGetUniformLocation(ID, name.c_str()), value); 
     }

src/4.advanced_opengl/1.1.depth_testing/depth_testing.cpp

@@ -7,7 +7,7 @@
 #include <glm/gtc/type_ptr.hpp>
 
 #include <learnopengl/filesystem.h>
-#include <learnopengl/shader_m.h>
+#include <learnopengl/shader.h>
 #include <learnopengl/camera.h>
 #include <learnopengl/model.h>
 

src/5.advanced_lighting/2.gamma_correction/gamma_correction.cpp

@@ -7,7 +7,7 @@
 #include <glm/gtc/type_ptr.hpp>
 
 #include <learnopengl/filesystem.h>
-#include <learnopengl/shader_m.h>
+#include <learnopengl/shader.h>
 #include <learnopengl/camera.h>
 #include <learnopengl/model.h>
 

src/5.advanced_lighting/3.1.1.shadow_mapping_depth/3.1.1.debug_quad.vs

@@ -1,11 +1,11 @@
 #version 330 core
-layout (location = 0) in vec3 position;
+layout (location = 0) in vec3 aPos;
-layout (location = 1) in vec2 texCoords;
+layout (location = 1) in vec2 aTexCoords;
 
 out vec2 TexCoords;
 
 void main()
 {
-    gl_Position = vec4(position, 1.0f);
+    TexCoords = aTexCoords;
-    TexCoords = texCoords;
+    gl_Position = vec4(aPos, 1.0);
 }

src/5.advanced_lighting/3.1.1.shadow_mapping_depth/3.1.1.debug_quad_depth.fs

@@ -1,11 +1,13 @@
 #version 330 core
-out vec4 color;
+out vec4 FragColor;
+
 in vec2 TexCoords;
 
 uniform sampler2D depthMap;
 uniform float near_plane;
 uniform float far_plane;
 
+// required when using a perspective projection matrix
 float LinearizeDepth(float depth)
 {
     float z = depth * 2.0 - 1.0; // Back to NDC 
@@ -16,5 +18,5 @@ void main()
 {             
     float depthValue = texture(depthMap, TexCoords).r;
     // color = vec4(vec3(LinearizeDepth(depthValue) / far_plane), 1.0); // perspective
-    color = vec4(vec3(depthValue), 1.0); // orthographic
+    FragColor = vec4(vec3(depthValue), 1.0); // orthographic
 }

src/5.advanced_lighting/3.1.1.shadow_mapping_depth/3.1.1.shadow_mapping_depth.vs

@@ -1,10 +1,10 @@
 #version 330 core
-layout (location = 0) in vec3 position;
+layout (location = 0) in vec3 aPos;
 
 uniform mat4 lightSpaceMatrix;
 uniform mat4 model;
 
 void main()
 {
-    gl_Position = lightSpaceMatrix * model * vec4(position, 1.0f);
+    gl_Position = lightSpaceMatrix * model * vec4(aPos, 1.0f);
 }

src/5.advanced_lighting/3.1.1.shadow_mapping_depth/shadow_mapping_depth.cpp

@@ -1,416 +1,381 @@
-// GLEW
+#include <glad/glad.h>
-#define GLEW_STATIC
-#include <GL/glew.h>
-
-// GLFW
 #include <GLFW/glfw3.h>
+#include <stb_image.h>
 
-// GL includes
-#include <learnopengl/shader.h>
-#include <learnopengl/camera.h>
-
-// GLM Mathemtics
 #include <glm/glm.hpp>
 #include <glm/gtc/matrix_transform.hpp>
 #include <glm/gtc/type_ptr.hpp>
 
-// Other Libs
-#include <SOIL.h>
 #include <learnopengl/filesystem.h>
+#include <learnopengl/shader.h>
+#include <learnopengl/camera.h>
+#include <learnopengl/model.h>
 
-// Properties
+#include <iostream>
-const GLuint SCR_WIDTH = 800, SCR_HEIGHT = 600;
 
-// Function prototypes
+void framebuffer_size_callback(GLFWwindow* window, int width, int height);
-void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);
-void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
 void mouse_callback(GLFWwindow* window, double xpos, double ypos);
-void Do_Movement();
+void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
-GLuint loadTexture(GLchar const * path);
+void processInput(GLFWwindow *window);
-void RenderScene(Shader &shader);
+unsigned int loadTexture(const char *path);
-void RenderCube();
+void renderScene(const Shader &shader);
-void RenderQuad();
+void renderCube();
+void renderQuad();
 
-// Camera
+// settings
+const unsigned int SCR_WIDTH = 1280;
+const unsigned int SCR_HEIGHT = 720;
+
+// camera
 Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
+float lastX = (float)SCR_WIDTH / 2.0;
+float lastY = (float)SCR_HEIGHT / 2.0;
+bool firstMouse = true;
 
-// Delta
+// timing
-GLfloat deltaTime = 0.0f;
+float deltaTime = 0.0f;
-GLfloat lastFrame = 0.0f;
+float lastFrame = 0.0f;
 
-// Options
+// meshes
-GLboolean shadows = true;
+unsigned int planeVAO;
 
-// Global variables
-GLuint woodTexture;
-GLuint planeVAO;
-
-// The MAIN function, from here we start our application and run our Game loop
 int main()
 {
-    // Init GLFW
+    // glfw: initialize and configure
+    // ------------------------------
     glfwInit();
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
     glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
-    glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
 
-    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", nullptr, nullptr); // Windowed
+    // glfw window creation
+    // --------------------
+    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
     glfwMakeContextCurrent(window);
-
+    if (window == NULL)
-    // Set the required callback functions
+    {
-    glfwSetKeyCallback(window, key_callback);
+        std::cout << "Failed to create GLFW window" << std::endl;
+        glfwTerminate();
+        return -1;
+    }
+    glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
     glfwSetCursorPosCallback(window, mouse_callback);
     glfwSetScrollCallback(window, scroll_callback);
 
-    // Options
+    // tell GLFW to capture our mouse
     glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
 
-    // Initialize GLEW to setup the OpenGL Function pointers
+    // glad: load all OpenGL function pointers
-    glewExperimental = GL_TRUE;
+    // ---------------------------------------
-    glewInit();
+    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
+    {
+        std::cout << "Failed to initialize GLAD" << std::endl;
+        return -1;
+    }
 
-    // Define the viewport dimensions
+    // configure global opengl state
-    glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+    // -----------------------------
-
-    // Setup some OpenGL options
     glEnable(GL_DEPTH_TEST);
 
-    // Setup and compile our shaders
+    // build and compile shaders
-    Shader shader("shadow_mapping.vs", "shadow_mapping.frag");
+    // -------------------------
-    Shader simpleDepthShader("shadow_mapping_depth.vs", "shadow_mapping_depth.frag");
+    Shader simpleDepthShader("3.1.1.shadow_mapping_depth.vs", "3.1.1.shadow_mapping_depth.fs");
-    Shader debugDepthQuad("debug_quad.vs", "debug_quad_depth.frag");
+    Shader debugDepthQuad("3.1.1.debug_quad.vs", "3.1.1.debug_quad_depth.fs");
 
-    // Set texture samples
+    // set up vertex data (and buffer(s)) and configure vertex attributes
-    shader.Use();
+    // ------------------------------------------------------------------
-    glUniform1i(glGetUniformLocation(shader.Program, "diffuseTexture"), 0);
+    float planeVertices[] = {
-    glUniform1i(glGetUniformLocation(shader.Program, "shadowMap"), 1);
+        // positions            // normals         // texcoords
+         25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,  25.0f,  0.0f,
+        -25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,   0.0f,  0.0f,
+        -25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,   0.0f, 25.0f,
 
-    GLfloat planeVertices[] = {
-        // Positions            // Normals           // Texture Coords
          25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,  25.0f,  0.0f,
         -25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,   0.0f, 25.0f,
-        -25.0f, -0.5f,  25.0f,  0.0f,  1.0f,  0.0f,  0.0f,  0.0f,
+         25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,  25.0f, 10.0f
-
-         25.0f, -0.5f,  25.0f,  0.0f,  1.0f,  0.0f,  25.0f, 0.0f,
-         25.0f, -0.5f, -25.0f,  0.0f,  1.0f,  0.0f,  25.0f, 25.0f,
-        -25.0f, -0.5f, -25.0f,  0.0f,  1.0f,  0.0f,  0.0f,  25.0f
     };
-    // Setup plane VAO
+    // plane VAO
-    GLuint planeVBO;
+    unsigned int planeVBO;
     glGenVertexArrays(1, &planeVAO);
     glGenBuffers(1, &planeVBO);
     glBindVertexArray(planeVAO);
     glBindBuffer(GL_ARRAY_BUFFER, planeVBO);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), &planeVertices, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), planeVertices, GL_STATIC_DRAW);
     glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
     glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
     glEnableVertexAttribArray(2);
-    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
     glBindVertexArray(0);
 
-    // Light source
+    // load textures
-    glm::vec3 lightPos(-2.0f, 4.0f, -1.0f);
+    // -------------
+    unsigned int woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
 
-    // Load textures
+    // configure depth map FBO
-    woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
+    // -----------------------
-
+    const unsigned int SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
-    // Configure depth map FBO
+    unsigned int depthMapFBO;
-    const GLuint SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
-    GLuint depthMapFBO;
     glGenFramebuffers(1, &depthMapFBO);
-    // - Create depth texture
+    // create depth texture
-    GLuint depthMap;
+    unsigned int depthMap;
     glGenTextures(1, &depthMap);
     glBindTexture(GL_TEXTURE_2D, depthMap);
-
     glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, SHADOW_WIDTH, SHADOW_HEIGHT, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    GLfloat borderColor[] = { 1.0, 1.0, 1.0, 1.0 };
+    // attach depth texture as FBO's depth buffer
-    glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
-
     glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
     glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthMap, 0);
     glDrawBuffer(GL_NONE);
     glReadBuffer(GL_NONE);
     glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
-    glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
 
-    // Game loop
+    // shader configuration
+    // --------------------
+    debugDepthQuad.use();
+    debugDepthQuad.setInt("depthMap", 0);
+
+    // lighting info
+    // -------------
+    glm::vec3 lightPos(-2.0f, 4.0f, -1.0f);
+
+    // render loop
+    // -----------
     while (!glfwWindowShouldClose(window))
     {
-        // Set frame time
+        // per-frame time logic
-        GLfloat currentFrame = glfwGetTime();
+        // --------------------
+        float currentFrame = glfwGetTime();
         deltaTime = currentFrame - lastFrame;
         lastFrame = currentFrame;
 
-        // Check and call events
+        // input
-        glfwPollEvents();
+        // -----
-        Do_Movement();
+        processInput(window);
 
-        // Change light position over time
+        // render
-        lightPos.z = cos(glfwGetTime()) * 2.0f;
+        // ------
+        glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-        // 1. Render depth of scene to texture (from light's perspective)
+        // 1. render depth of scene to texture (from light's perspective)
-        // - Get light projection/view matrix.
+        // --------------------------------------------------------------
         glm::mat4 lightProjection, lightView;
         glm::mat4 lightSpaceMatrix;
-        GLfloat near_plane = 1.0f, far_plane = 7.5f;
+        float near_plane = 1.0f, far_plane = 7.5f;
         lightProjection = glm::ortho(-10.0f, 10.0f, -10.0f, 10.0f, near_plane, far_plane);
-        //lightProjection = glm::perspective(45.0f, (GLfloat)SHADOW_WIDTH / (GLfloat)SHADOW_HEIGHT, near_plane, far_plane); // Note that if you use a perspective projection matrix you'll have to change the light position as the current light position isn't enough to reflect the whole scene.
         lightView = glm::lookAt(lightPos, glm::vec3(0.0f), glm::vec3(0.0, 1.0, 0.0));
         lightSpaceMatrix = lightProjection * lightView;
-        // - now render scene from light's point of view
+        // render scene from light's point of view
-        simpleDepthShader.Use();
+        simpleDepthShader.use();
-        glUniformMatrix4fv(glGetUniformLocation(simpleDepthShader.Program, "lightSpaceMatrix"), 1, GL_FALSE, glm::value_ptr(lightSpaceMatrix));
+        simpleDepthShader.setMat4("lightSpaceMatrix", lightSpaceMatrix);
+
         glViewport(0, 0, SHADOW_WIDTH, SHADOW_HEIGHT);
         glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
             glClear(GL_DEPTH_BUFFER_BIT);
-            RenderScene(simpleDepthShader);
-        glBindFramebuffer(GL_FRAMEBUFFER, 0);
-
-        // 2. Render scene as normal
-        glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-        shader.Use();
-        glm::mat4 projection = glm::perspective(camera.Zoom, (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
-        glm::mat4 view = camera.GetViewMatrix();
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "projection"), 1, GL_FALSE, glm::value_ptr(projection));
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "view"), 1, GL_FALSE, glm::value_ptr(view));
-        // Set light uniforms
-        glUniform3fv(glGetUniformLocation(shader.Program, "lightPos"), 1, &lightPos[0]);
-        glUniform3fv(glGetUniformLocation(shader.Program, "viewPos"), 1, &camera.Position[0]);
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "lightSpaceMatrix"), 1, GL_FALSE, glm::value_ptr(lightSpaceMatrix));
-        // Enable/Disable shadows by pressing 'SPACE'
-        glUniform1i(glGetUniformLocation(shader.Program, "shadows"), shadows);
             glActiveTexture(GL_TEXTURE0);
             glBindTexture(GL_TEXTURE_2D, woodTexture);
-        glActiveTexture(GL_TEXTURE1);
+            renderScene(simpleDepthShader);
-        glBindTexture(GL_TEXTURE_2D, depthMap);
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
-        RenderScene(shader);
 
-        // 3. DEBUG: visualize depth map by rendering it to plane
+        // reset viewport
-        debugDepthQuad.Use();
+        glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
-        glUniform1f(glGetUniformLocation(debugDepthQuad.Program, "near_plane"), near_plane);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-        glUniform1f(glGetUniformLocation(debugDepthQuad.Program, "far_plane"), far_plane);
+
+        // render Depth map to quad for visual debugging
+        // ---------------------------------------------
+        debugDepthQuad.use();
+        debugDepthQuad.setFloat("near_plane", near_plane);
+        debugDepthQuad.setFloat("far_plane", far_plane);
         glActiveTexture(GL_TEXTURE0);
         glBindTexture(GL_TEXTURE_2D, depthMap);
-        //RenderQuad(); // uncomment this line to see depth map
+        renderQuad();
 
-
+        // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
-        // Swap the buffers
+        // -------------------------------------------------------------------------------
         glfwSwapBuffers(window);
+        glfwPollEvents();
     }
 
+    // optional: de-allocate all resources once they've outlived their purpose:
+    // ------------------------------------------------------------------------
+    glDeleteVertexArrays(1, &planeVAO);
+    glDeleteBuffers(1, &planeVBO);
+
     glfwTerminate();
     return 0;
 }
 
-void RenderScene(Shader &shader)
+// renders the 3D scene
+// --------------------
+void renderScene(const Shader &shader)
 {
-    // Floor
+    // floor
     glm::mat4 model;
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    shader.setMat4("model", model);
     glBindVertexArray(planeVAO);
     glDrawArrays(GL_TRIANGLES, 0, 6);
-    glBindVertexArray(0);
+    // cubes
-    // Cubes
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(0.0f, 1.5f, 0.0));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    model = glm::scale(model, glm::vec3(0.5f));
-    RenderCube();
+    shader.setMat4("model", model);
+    renderCube();
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(2.0f, 0.0f, 1.0));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    model = glm::scale(model, glm::vec3(0.5f));
-    RenderCube();
+    shader.setMat4("model", model);
+    renderCube();
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(-1.0f, 0.0f, 2.0));
-    model = glm::rotate(model, 60.0f, glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
+    model = glm::rotate(model, glm::radians(60.0f), glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
-    model = glm::scale(model, glm::vec3(0.5));
+    model = glm::scale(model, glm::vec3(0.25));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    shader.setMat4("model", model);
-    RenderCube();
+    renderCube();
 }
 
 
-// RenderQuad() Renders a 1x1 quad in NDC, best used for framebuffer color targets
+// renderCube() renders a 1x1 3D cube in NDC.
-// and post-processing effects.
+// -------------------------------------------------
-GLuint quadVAO = 0;
+unsigned int cubeVAO = 0;
-GLuint quadVBO;
+unsigned int cubeVBO = 0;
-void RenderQuad()
+void renderCube()
+{
+    // initialize (if necessary)
+    if (cubeVAO == 0)
+    {
+        float vertices[] = {
+            // back face
+            -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
+             1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 1.0f, // top-right
+             1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 0.0f, // bottom-right         
+             1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 1.0f, // top-right
+            -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
+            -1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 1.0f, // top-left
+            // front face
+            -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 0.0f, // bottom-left
+             1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 0.0f, // bottom-right
+             1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 1.0f, // top-right
+             1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 1.0f, // top-right
+            -1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 1.0f, // top-left
+            -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 0.0f, // bottom-left
+            // left face
+            -1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-right
+            -1.0f,  1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 1.0f, // top-left
+            -1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-left
+            -1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-left
+            -1.0f, -1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 0.0f, // bottom-right
+            -1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-right
+            // right face
+             1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-left
+             1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-right
+             1.0f,  1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 1.0f, // top-right         
+             1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-right
+             1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-left
+             1.0f, -1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 0.0f, // bottom-left     
+            // bottom face
+            -1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 1.0f, // top-right
+             1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 1.0f, // top-left
+             1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 0.0f, // bottom-left
+             1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 0.0f, // bottom-left
+            -1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 0.0f, // bottom-right
+            -1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 1.0f, // top-right
+            // top face
+            -1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 1.0f, // top-left
+             1.0f,  1.0f , 1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 0.0f, // bottom-right
+             1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 1.0f, // top-right     
+             1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 0.0f, // bottom-right
+            -1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 1.0f, // top-left
+            -1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 0.0f  // bottom-left        
+        };
+        glGenVertexArrays(1, &cubeVAO);
+        glGenBuffers(1, &cubeVBO);
+        // fill buffer
+        glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
+        glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+        // link vertex attributes
+        glBindVertexArray(cubeVAO);
+        glEnableVertexAttribArray(0);
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
+        glEnableVertexAttribArray(1);
+        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
+        glEnableVertexAttribArray(2);
+        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        glBindVertexArray(0);
+    }
+    // render Cube
+    glBindVertexArray(cubeVAO);
+    glDrawArrays(GL_TRIANGLES, 0, 36);
+    glBindVertexArray(0);
+}
+
+// renderQuad() renders a 1x1 XY quad in NDC
+// -----------------------------------------
+unsigned int quadVAO = 0;
+unsigned int quadVBO;
+void renderQuad()
 {
     if (quadVAO == 0)
     {
-        GLfloat quadVertices[] = {
+        float quadVertices[] = {
-            // Positions        // Texture Coords
+            // positions        // texture Coords
             -1.0f,  1.0f, 0.0f, 0.0f, 1.0f,
             -1.0f, -1.0f, 0.0f, 0.0f, 0.0f,
              1.0f,  1.0f, 0.0f, 1.0f, 1.0f,
              1.0f, -1.0f, 0.0f, 1.0f, 0.0f,
         };
-        // Setup plane VAO
+        // setup plane VAO
         glGenVertexArrays(1, &quadVAO);
         glGenBuffers(1, &quadVBO);
         glBindVertexArray(quadVAO);
         glBindBuffer(GL_ARRAY_BUFFER, quadVBO);
         glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
         glEnableVertexAttribArray(0);
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)0);
         glEnableVertexAttribArray(1);
-        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
+        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
     }
     glBindVertexArray(quadVAO);
     glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
     glBindVertexArray(0);
 }
 
-// RenderCube() Renders a 1x1 3D cube in NDC.
+// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
-GLuint cubeVAO = 0;
+// ---------------------------------------------------------------------------------------------------------
-GLuint cubeVBO = 0;
+void processInput(GLFWwindow *window)
-void RenderCube()
 {
-    // Initialize (if necessary)
+    if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
-    if (cubeVAO == 0)
+        glfwSetWindowShouldClose(window, true);
-    {
-        GLfloat vertices[] = {
-            // Back face
-            -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // Bottom-left
-            0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,  // top-right
-            -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,  // bottom-left
-            -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f,// top-left
-            // Front face
-            -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
-            0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f,  // bottom-right
-            0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,  // top-right
-            0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
-            -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f,  // top-left
-            -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,  // bottom-left
-            // Left face
-            -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-            -0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-left
-            -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,  // bottom-left
-            -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-            -0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f,  // bottom-right
-            -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-            // Right face
-            0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
-            0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,  // bottom-right
-            0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,  // top-left
-            0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-left
-            // Bottom face
-            -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f, // top-left
-            0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,// bottom-left
-            0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, // bottom-left
-            -0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-            -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
-            // Top face
-            -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-            0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, // top-right
-            0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-            -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-            -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f // bottom-left
-        };
-        glGenVertexArrays(1, &cubeVAO);
-        glGenBuffers(1, &cubeVBO);
-        // Fill buffer
-        glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
-        glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
-        // Link vertex attributes
-        glBindVertexArray(cubeVAO);
-        glEnableVertexAttribArray(0);
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
-        glEnableVertexAttribArray(1);
-        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
-        glEnableVertexAttribArray(2);
-        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
-        glBindVertexArray(0);
-    }
-    // Render Cube
-    glBindVertexArray(cubeVAO);
-    glDrawArrays(GL_TRIANGLES, 0, 36);
-    glBindVertexArray(0);
-}
 
-// This function loads a texture from file. Note: texture loading functions like these are usually
+    float cameraSpeed = 2.5 * deltaTime;
-// managed by a 'Resource Manager' that manages all resources (like textures, models, audio).
+    if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS)
-// For learning purposes we'll just define it as a utility function.
-GLuint loadTexture(GLchar const * path)
-{
-    // Generate texture ID and load texture data
-    GLuint textureID;
-    glGenTextures(1, &textureID);
-    int width, height;
-    unsigned char* image = SOIL_load_image(path, &width, &height, 0, SOIL_LOAD_RGB);
-    // Assign texture to ID
-    glBindTexture(GL_TEXTURE_2D, textureID);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
-    glGenerateMipmap(GL_TEXTURE_2D);
-
-    // Parameters
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-    glBindTexture(GL_TEXTURE_2D, 0);
-    SOIL_free_image_data(image);
-    return textureID;
-
-}
-
-bool keys[1024];
-bool keysPressed[1024];
-// Moves/alters the camera positions based on user input
-void Do_Movement()
-{
-    // Camera controls
-    if (keys[GLFW_KEY_W])
         camera.ProcessKeyboard(FORWARD, deltaTime);
-    if (keys[GLFW_KEY_S])
+    if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS)
         camera.ProcessKeyboard(BACKWARD, deltaTime);
-    if (keys[GLFW_KEY_A])
+    if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS)
         camera.ProcessKeyboard(LEFT, deltaTime);
-    if (keys[GLFW_KEY_D])
+    if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS)
         camera.ProcessKeyboard(RIGHT, deltaTime);
-
-    if (keys[GLFW_KEY_SPACE] && !keysPressed[GLFW_KEY_SPACE])
-    {
-        shadows = !shadows;
-        keysPressed[GLFW_KEY_SPACE] = true;
-    }
 }
 
-GLfloat lastX = 400, lastY = 300;
+// glfw: whenever the window size changed (by OS or user resize) this callback function executes
-bool firstMouse = true;
+// ---------------------------------------------------------------------------------------------
-// Is called whenever a key is pressed/released via GLFW
+void framebuffer_size_callback(GLFWwindow* window, int width, int height)
-void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
 {
-    if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
+    // make sure the viewport matches the new window dimensions; note that width and 
-        glfwSetWindowShouldClose(window, GL_TRUE);
+    // height will be significantly larger than specified on retina displays.
-
+    glViewport(0, 0, width, height);
-    if (key >= 0 && key <= 1024)
-    {
-        if (action == GLFW_PRESS)
-            keys[key] = true;
-        else if (action == GLFW_RELEASE)
-        {
-            keys[key] = false;
-            keysPressed[key] = false;
-        }
-    }
 }
 
+
+// glfw: whenever the mouse moves, this callback is called
+// -------------------------------------------------------
 void mouse_callback(GLFWwindow* window, double xpos, double ypos)
 {
     if (firstMouse)
@@ -420,8 +385,8 @@ void mouse_callback(GLFWwindow* window, double xpos, double ypos)
         firstMouse = false;
     }
 
-    GLfloat xoffset = xpos - lastX;
+    float xoffset = xpos - lastX;
-    GLfloat yoffset = lastY - ypos;
+    float yoffset = lastY - ypos; // reversed since y-coordinates go from bottom to top
 
     lastX = xpos;
     lastY = ypos;
@@ -429,7 +394,48 @@ void mouse_callback(GLFWwindow* window, double xpos, double ypos)
     camera.ProcessMouseMovement(xoffset, yoffset);
 }
 
+// glfw: whenever the mouse scroll wheel scrolls, this callback is called
+// ----------------------------------------------------------------------
 void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
 {
     camera.ProcessMouseScroll(yoffset);
 }
+
+// utility function for loading a 2D texture from file
+// ---------------------------------------------------
+unsigned int loadTexture(char const * path)
+{
+    unsigned int textureID;
+    glGenTextures(1, &textureID);
+
+    int width, height, nrComponents;
+    unsigned char *data = stbi_load(path, &width, &height, &nrComponents, 0);
+    if (data)
+    {
+        GLenum format;
+        if (nrComponents == 1)
+            format = GL_RED;
+        else if (nrComponents == 3)
+            format = GL_RGB;
+        else if (nrComponents == 4)
+            format = GL_RGBA;
+
+        glBindTexture(GL_TEXTURE_2D, textureID);
+        glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
+        glGenerateMipmap(GL_TEXTURE_2D);
+
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT); // for this tutorial: use GL_CLAMP_TO_EDGE to prevent semi-transparent borders. Due to interpolation it takes texels from next repeat 
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+        stbi_image_free(data);
+    }
+    else
+    {
+        std::cout << "Texture failed to load at path: " << path << std::endl;
+        stbi_image_free(data);
+    }
+
+    return textureID;
+}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/3.1.2.shadow_mapping.fs

@@ -14,8 +14,6 @@ uniform sampler2D shadowMap;
 uniform vec3 lightPos;
 uniform vec3 viewPos;
 
-uniform bool shadows;
-
 float ShadowCalculation(vec4 fragPosLightSpace)
 {
     // perform perspective divide
@@ -26,28 +24,8 @@ float ShadowCalculation(vec4 fragPosLightSpace)
     float closestDepth = texture(shadowMap, projCoords.xy).r; 
     // Get depth of current fragment from light's perspective
     float currentDepth = projCoords.z;
-    // Calculate bias (based on depth map resolution and slope)
-    vec3 normal = normalize(fs_in.Normal);
-    vec3 lightDir = normalize(lightPos - fs_in.FragPos);
-    float bias = max(0.05 * (1.0 - dot(normal, lightDir)), 0.005);
     // Check whether current frag pos is in shadow
-    // float shadow = currentDepth - bias > closestDepth  ? 1.0 : 0.0;
+    float shadow = currentDepth > closestDepth  ? 1.0 : 0.0;
-    // PCF
-    float shadow = 0.0;
-    vec2 texelSize = 1.0 / textureSize(shadowMap, 0);
-    for(int x = -1; x <= 1; ++x)
-    {
-        for(int y = -1; y <= 1; ++y)
-        {
-            float pcfDepth = texture(shadowMap, projCoords.xy + vec2(x, y) * texelSize).r; 
-            shadow += currentDepth - bias > pcfDepth  ? 1.0 : 0.0;        
-        }    
-    }
-    shadow /= 9.0;
-    
-    // Keep the shadow at 0.0 when outside the far_plane region of the light's frustum.
-    if(projCoords.z > 1.0)
-        shadow = 0.0;
 
     return shadow;
 }
@@ -57,22 +35,22 @@ void main()
     vec3 color = texture(diffuseTexture, fs_in.TexCoords).rgb;
     vec3 normal = normalize(fs_in.Normal);
     vec3 lightColor = vec3(0.3);
-    // Ambient
+    // ambient
     vec3 ambient = 0.3 * color;
-    // Diffuse
+    // diffuse
     vec3 lightDir = normalize(lightPos - fs_in.FragPos);
     float diff = max(dot(lightDir, normal), 0.0);
     vec3 diffuse = diff * lightColor;
-    // Specular
+    // specular
     vec3 viewDir = normalize(viewPos - fs_in.FragPos);
     vec3 reflectDir = reflect(-lightDir, normal);
     float spec = 0.0;
     vec3 halfwayDir = normalize(lightDir + viewDir);  
     spec = pow(max(dot(normal, halfwayDir), 0.0), 64.0);
     vec3 specular = spec * lightColor;    
-    // Calculate shadow
+    // calculate shadow
-    float shadow = shadows ? ShadowCalculation(fs_in.FragPosLightSpace) : 0.0;                      
+    float shadow = ShadowCalculation(fs_in.FragPosLightSpace);                      
     vec3 lighting = (ambient + (1.0 - shadow) * (diffuse + specular)) * color;    
     
-    FragColor = vec4(lighting, 1.0f);
+    FragColor = vec4(lighting, 1.0);
 }

src/5.advanced_lighting/3.1.2.shadow_mapping_base/3.1.2.shadow_mapping.vs

@@ -0,0 +1,27 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aNormal;
+layout (location = 2) in vec2 aTexCoords;
+
+out vec2 TexCoords;
+
+out VS_OUT {
+    vec3 FragPos;
+    vec3 Normal;
+    vec2 TexCoords;
+    vec4 FragPosLightSpace;
+} vs_out;
+
+uniform mat4 projection;
+uniform mat4 view;
+uniform mat4 model;
+uniform mat4 lightSpaceMatrix;
+
+void main()
+{
+    vs_out.FragPos = vec3(model * vec4(aPos, 1.0));
+    vs_out.Normal = transpose(inverse(mat3(model))) * aNormal;
+    vs_out.TexCoords = aTexCoords;
+    vs_out.FragPosLightSpace = lightSpaceMatrix * vec4(vs_out.FragPos, 1.0);
+    gl_Position = projection * view * model * vec4(aPos, 1.0f);
+}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/debug_quad.vs

@@ -1,11 +0,0 @@
-#version 330 core
-layout (location = 0) in vec3 position;
-layout (location = 1) in vec2 texCoords;
-
-out vec2 TexCoords;
-
-void main()
-{
-    gl_Position = vec4(position, 1.0f);
-    TexCoords = texCoords;
-}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/debug_quad_depth.fs

@@ -1,20 +0,0 @@
-#version 330 core
-out vec4 color;
-in vec2 TexCoords;
-
-uniform sampler2D depthMap;
-uniform float near_plane;
-uniform float far_plane;
-
-float LinearizeDepth(float depth)
-{
-    float z = depth * 2.0 - 1.0; // Back to NDC 
-    return (2.0 * near_plane * far_plane) / (far_plane + near_plane - z * (far_plane - near_plane));	
-}
-
-void main()
-{             
-    float depthValue = texture(depthMap, TexCoords).r;
-    // color = vec4(vec3(LinearizeDepth(depthValue) / far_plane), 1.0); // perspective
-    color = vec4(vec3(depthValue), 1.0); // orthographic
-}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/shadow_mapping.vs

@@ -1,27 +0,0 @@
-#version 330 core
-layout (location = 0) in vec3 position;
-layout (location = 1) in vec3 normal;
-layout (location = 2) in vec2 texCoords;
-
-out vec2 TexCoords;
-
-out VS_OUT {
-    vec3 FragPos;
-    vec3 Normal;
-    vec2 TexCoords;
-    vec4 FragPosLightSpace;
-} vs_out;
-
-uniform mat4 projection;
-uniform mat4 view;
-uniform mat4 model;
-uniform mat4 lightSpaceMatrix;
-
-void main()
-{
-    gl_Position = projection * view * model * vec4(position, 1.0f);
-    vs_out.FragPos = vec3(model * vec4(position, 1.0));
-    vs_out.Normal = transpose(inverse(mat3(model))) * normal;
-    vs_out.TexCoords = texCoords;
-    vs_out.FragPosLightSpace = lightSpaceMatrix * vec4(vs_out.FragPos, 1.0);
-}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/shadow_mapping_base.cpp

@@ -1,416 +1,404 @@
-// GLEW
+#include <glad/glad.h>
-#define GLEW_STATIC
-#include <GL/glew.h>
-
-// GLFW
 #include <GLFW/glfw3.h>
+#include <stb_image.h>
 
-// GL includes
-#include <learnopengl/shader.h>
-#include <learnopengl/camera.h>
-
-// GLM Mathemtics
 #include <glm/glm.hpp>
 #include <glm/gtc/matrix_transform.hpp>
 #include <glm/gtc/type_ptr.hpp>
 
-// Other Libs
-#include <SOIL.h>
 #include <learnopengl/filesystem.h>
+#include <learnopengl/shader.h>
+#include <learnopengl/camera.h>
+#include <learnopengl/model.h>
 
-// Properties
+#include <iostream>
-const GLuint SCR_WIDTH = 800, SCR_HEIGHT = 600;
 
-// Function prototypes
+void framebuffer_size_callback(GLFWwindow* window, int width, int height);
-void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);
-void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
 void mouse_callback(GLFWwindow* window, double xpos, double ypos);
-void Do_Movement();
+void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
-GLuint loadTexture(GLchar const * path);
+void processInput(GLFWwindow *window);
-void RenderScene(Shader &shader);
+unsigned int loadTexture(const char *path);
-void RenderCube();
+void renderScene(const Shader &shader);
-void RenderQuad();
+void renderCube();
+void renderQuad();
 
-// Camera
+// settings
+const unsigned int SCR_WIDTH = 1280;
+const unsigned int SCR_HEIGHT = 720;
+
+// camera
 Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
+float lastX = (float)SCR_WIDTH / 2.0;
+float lastY = (float)SCR_HEIGHT / 2.0;
+bool firstMouse = true;
 
-// Delta
+// timing
-GLfloat deltaTime = 0.0f;
+float deltaTime = 0.0f;
-GLfloat lastFrame = 0.0f;
+float lastFrame = 0.0f;
 
-// Options
+// meshes
-GLboolean shadows = true;
+unsigned int planeVAO;
 
-// Global variables
-GLuint woodTexture;
-GLuint planeVAO;
-
-// The MAIN function, from here we start our application and run our Game loop
 int main()
 {
-    // Init GLFW
+    // glfw: initialize and configure
+    // ------------------------------
     glfwInit();
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
     glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
-    glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
 
-    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", nullptr, nullptr); // Windowed
+    // glfw window creation
+    // --------------------
+    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
     glfwMakeContextCurrent(window);
-
+    if (window == NULL)
-    // Set the required callback functions
+    {
-    glfwSetKeyCallback(window, key_callback);
+        std::cout << "Failed to create GLFW window" << std::endl;
+        glfwTerminate();
+        return -1;
+    }
+    glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
     glfwSetCursorPosCallback(window, mouse_callback);
     glfwSetScrollCallback(window, scroll_callback);
 
-    // Options
+    // tell GLFW to capture our mouse
     glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
 
-    // Initialize GLEW to setup the OpenGL Function pointers
+    // glad: load all OpenGL function pointers
-    glewExperimental = GL_TRUE;
+    // ---------------------------------------
-    glewInit();
+    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
+    {
+        std::cout << "Failed to initialize GLAD" << std::endl;
+        return -1;
+    }
 
-    // Define the viewport dimensions
+    // configure global opengl state
-    glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+    // -----------------------------
-
-    // Setup some OpenGL options
     glEnable(GL_DEPTH_TEST);
 
-    // Setup and compile our shaders
+    // build and compile shaders
-    Shader shader("shadow_mapping.vs", "shadow_mapping.frag");
+    // -------------------------
-    Shader simpleDepthShader("shadow_mapping_depth.vs", "shadow_mapping_depth.frag");
+    Shader shader("3.1.2.shadow_mapping.vs", "3.1.2.shadow_mapping.fs");
-    Shader debugDepthQuad("debug_quad.vs", "debug_quad_depth.frag");
+    Shader simpleDepthShader("3.1.1.shadow_mapping_depth.vs", "3.1.1.shadow_mapping_depth.fs");
+    Shader debugDepthQuad("3.1.1.debug_quad.vs", "3.1.1.debug_quad_depth.fs");
 
-    // Set texture samples
+    // set up vertex data (and buffer(s)) and configure vertex attributes
-    shader.Use();
+    // ------------------------------------------------------------------
-    glUniform1i(glGetUniformLocation(shader.Program, "diffuseTexture"), 0);
+    float planeVertices[] = {
-    glUniform1i(glGetUniformLocation(shader.Program, "shadowMap"), 1);
+        // positions            // normals         // texcoords
+         25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,  25.0f,  0.0f,
+        -25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,   0.0f,  0.0f,
+        -25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,   0.0f, 25.0f,
 
-    GLfloat planeVertices[] = {
-        // Positions            // Normals           // Texture Coords
          25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,  25.0f,  0.0f,
         -25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,   0.0f, 25.0f,
-        -25.0f, -0.5f,  25.0f,  0.0f,  1.0f,  0.0f,  0.0f,  0.0f,
+         25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,  25.0f, 25.0f
-
-         25.0f, -0.5f,  25.0f,  0.0f,  1.0f,  0.0f,  25.0f, 0.0f,
-         25.0f, -0.5f, -25.0f,  0.0f,  1.0f,  0.0f,  25.0f, 25.0f,
-        -25.0f, -0.5f, -25.0f,  0.0f,  1.0f,  0.0f,  0.0f,  25.0f
     };
-    // Setup plane VAO
+    // plane VAO
-    GLuint planeVBO;
+    unsigned int planeVBO;
     glGenVertexArrays(1, &planeVAO);
     glGenBuffers(1, &planeVBO);
     glBindVertexArray(planeVAO);
     glBindBuffer(GL_ARRAY_BUFFER, planeVBO);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), &planeVertices, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), planeVertices, GL_STATIC_DRAW);
     glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
     glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
     glEnableVertexAttribArray(2);
-    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
     glBindVertexArray(0);
 
-    // Light source
+    // load textures
-    glm::vec3 lightPos(-2.0f, 4.0f, -1.0f);
+    // -------------
+    unsigned int woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
 
-    // Load textures
+    // configure depth map FBO
-    woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
+    // -----------------------
-
+    const unsigned int SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
-    // Configure depth map FBO
+    unsigned int depthMapFBO;
-    const GLuint SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
-    GLuint depthMapFBO;
     glGenFramebuffers(1, &depthMapFBO);
-    // - Create depth texture
+    // create depth texture
-    GLuint depthMap;
+    unsigned int depthMap;
     glGenTextures(1, &depthMap);
     glBindTexture(GL_TEXTURE_2D, depthMap);
-
     glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, SHADOW_WIDTH, SHADOW_HEIGHT, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    GLfloat borderColor[] = { 1.0, 1.0, 1.0, 1.0 };
+    // attach depth texture as FBO's depth buffer
-    glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
-
     glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
     glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthMap, 0);
     glDrawBuffer(GL_NONE);
     glReadBuffer(GL_NONE);
     glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
-    glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
 
-    // Game loop
+    // shader configuration
+    // --------------------
+    shader.use();
+    shader.setInt("diffuseTexture", 0);
+    shader.setInt("shadowMap", 1);
+    debugDepthQuad.use();
+    debugDepthQuad.setInt("depthMap", 0);
+
+    // lighting info
+    // -------------
+    glm::vec3 lightPos(-2.0f, 4.0f, -1.0f);
+
+    // render loop
+    // -----------
     while (!glfwWindowShouldClose(window))
     {
-        // Set frame time
+        // per-frame time logic
-        GLfloat currentFrame = glfwGetTime();
+        // --------------------
+        float currentFrame = glfwGetTime();
         deltaTime = currentFrame - lastFrame;
         lastFrame = currentFrame;
 
-        // Check and call events
+        // input
-        glfwPollEvents();
+        // -----
-        Do_Movement();
+        processInput(window);
 
-        // Change light position over time
+        // render
-        lightPos.z = cos(glfwGetTime()) * 2.0f;
+        // ------
+        glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-        // 1. Render depth of scene to texture (from light's perspective)
+        // 1. render depth of scene to texture (from light's perspective)
-        // - Get light projection/view matrix.
+        // --------------------------------------------------------------
         glm::mat4 lightProjection, lightView;
         glm::mat4 lightSpaceMatrix;
-        GLfloat near_plane = 1.0f, far_plane = 7.5f;
+        float near_plane = 1.0f, far_plane = 7.5f;
         lightProjection = glm::ortho(-10.0f, 10.0f, -10.0f, 10.0f, near_plane, far_plane);
-        //lightProjection = glm::perspective(45.0f, (GLfloat)SHADOW_WIDTH / (GLfloat)SHADOW_HEIGHT, near_plane, far_plane); // Note that if you use a perspective projection matrix you'll have to change the light position as the current light position isn't enough to reflect the whole scene.
         lightView = glm::lookAt(lightPos, glm::vec3(0.0f), glm::vec3(0.0, 1.0, 0.0));
         lightSpaceMatrix = lightProjection * lightView;
-        // - now render scene from light's point of view
+        // render scene from light's point of view
-        simpleDepthShader.Use();
+        simpleDepthShader.use();
-        glUniformMatrix4fv(glGetUniformLocation(simpleDepthShader.Program, "lightSpaceMatrix"), 1, GL_FALSE, glm::value_ptr(lightSpaceMatrix));
+        simpleDepthShader.setMat4("lightSpaceMatrix", lightSpaceMatrix);
+
         glViewport(0, 0, SHADOW_WIDTH, SHADOW_HEIGHT);
         glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
             glClear(GL_DEPTH_BUFFER_BIT);
-            RenderScene(simpleDepthShader);
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, woodTexture);
+            renderScene(simpleDepthShader);
         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
-        // 2. Render scene as normal
+        // reset viewport
         glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-        shader.Use();
+
+        // 2. render scene as normal using the generated depth/shadow map  
+        // --------------------------------------------------------------
+        glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        shader.use();
         glm::mat4 projection = glm::perspective(camera.Zoom, (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
         glm::mat4 view = camera.GetViewMatrix();
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "projection"), 1, GL_FALSE, glm::value_ptr(projection));
+        shader.setMat4("projection", projection);
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "view"), 1, GL_FALSE, glm::value_ptr(view));
+        shader.setMat4("view", view);
-        // Set light uniforms
+        // set light uniforms
-        glUniform3fv(glGetUniformLocation(shader.Program, "lightPos"), 1, &lightPos[0]);
+        shader.setVec3("viewPos", camera.Position);
-        glUniform3fv(glGetUniformLocation(shader.Program, "viewPos"), 1, &camera.Position[0]);
+        shader.setVec3("lightPos", lightPos);
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "lightSpaceMatrix"), 1, GL_FALSE, glm::value_ptr(lightSpaceMatrix));
+        shader.setMat4("lightSpaceMatrix", lightSpaceMatrix);
-        // Enable/Disable shadows by pressing 'SPACE'
-        glUniform1i(glGetUniformLocation(shader.Program, "shadows"), shadows);
         glActiveTexture(GL_TEXTURE0);
         glBindTexture(GL_TEXTURE_2D, woodTexture);
         glActiveTexture(GL_TEXTURE1);
         glBindTexture(GL_TEXTURE_2D, depthMap);
-        RenderScene(shader);
+        renderScene(shader);
 
-        // 3. DEBUG: visualize depth map by rendering it to plane
+        // render Depth map to quad for visual debugging
-        debugDepthQuad.Use();
+        // ---------------------------------------------
-        glUniform1f(glGetUniformLocation(debugDepthQuad.Program, "near_plane"), near_plane);
+        debugDepthQuad.use();
-        glUniform1f(glGetUniformLocation(debugDepthQuad.Program, "far_plane"), far_plane);
+        debugDepthQuad.setFloat("near_plane", near_plane);
+        debugDepthQuad.setFloat("far_plane", far_plane);
         glActiveTexture(GL_TEXTURE0);
         glBindTexture(GL_TEXTURE_2D, depthMap);
-        //RenderQuad(); // uncomment this line to see depth map
+        //renderQuad();
 
-
+        // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
-        // Swap the buffers
+        // -------------------------------------------------------------------------------
         glfwSwapBuffers(window);
+        glfwPollEvents();
     }
 
+    // optional: de-allocate all resources once they've outlived their purpose:
+    // ------------------------------------------------------------------------
+    glDeleteVertexArrays(1, &planeVAO);
+    glDeleteBuffers(1, &planeVBO);
+
     glfwTerminate();
     return 0;
 }
 
-void RenderScene(Shader &shader)
+// renders the 3D scene
+// --------------------
+void renderScene(const Shader &shader)
 {
-    // Floor
+    // floor
     glm::mat4 model;
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    shader.setMat4("model", model);
     glBindVertexArray(planeVAO);
     glDrawArrays(GL_TRIANGLES, 0, 6);
-    glBindVertexArray(0);
+    // cubes
-    // Cubes
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(0.0f, 1.5f, 0.0));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    model = glm::scale(model, glm::vec3(0.5f));
-    RenderCube();
+    shader.setMat4("model", model);
+    renderCube();
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(2.0f, 0.0f, 1.0));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    model = glm::scale(model, glm::vec3(0.5f));
-    RenderCube();
+    shader.setMat4("model", model);
+    renderCube();
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(-1.0f, 0.0f, 2.0));
-    model = glm::rotate(model, 60.0f, glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
+    model = glm::rotate(model, glm::radians(60.0f), glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
-    model = glm::scale(model, glm::vec3(0.5));
+    model = glm::scale(model, glm::vec3(0.25));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    shader.setMat4("model", model);
-    RenderCube();
+    renderCube();
 }
 
 
-// RenderQuad() Renders a 1x1 quad in NDC, best used for framebuffer color targets
+// renderCube() renders a 1x1 3D cube in NDC.
-// and post-processing effects.
+// -------------------------------------------------
-GLuint quadVAO = 0;
+unsigned int cubeVAO = 0;
-GLuint quadVBO;
+unsigned int cubeVBO = 0;
-void RenderQuad()
+void renderCube()
+{
+    // initialize (if necessary)
+    if (cubeVAO == 0)
+    {
+        float vertices[] = {
+            // back face
+            -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
+             1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 1.0f, // top-right
+             1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 0.0f, // bottom-right         
+             1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 1.0f, // top-right
+            -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
+            -1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 1.0f, // top-left
+            // front face
+            -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 0.0f, // bottom-left
+             1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 0.0f, // bottom-right
+             1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 1.0f, // top-right
+             1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 1.0f, // top-right
+            -1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 1.0f, // top-left
+            -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 0.0f, // bottom-left
+            // left face
+            -1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-right
+            -1.0f,  1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 1.0f, // top-left
+            -1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-left
+            -1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-left
+            -1.0f, -1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 0.0f, // bottom-right
+            -1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-right
+            // right face
+             1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-left
+             1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-right
+             1.0f,  1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 1.0f, // top-right         
+             1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-right
+             1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-left
+             1.0f, -1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 0.0f, // bottom-left     
+            // bottom face
+            -1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 1.0f, // top-right
+             1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 1.0f, // top-left
+             1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 0.0f, // bottom-left
+             1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 0.0f, // bottom-left
+            -1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 0.0f, // bottom-right
+            -1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 1.0f, // top-right
+            // top face
+            -1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 1.0f, // top-left
+             1.0f,  1.0f , 1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 0.0f, // bottom-right
+             1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 1.0f, // top-right     
+             1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 0.0f, // bottom-right
+            -1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 1.0f, // top-left
+            -1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 0.0f  // bottom-left        
+        };
+        glGenVertexArrays(1, &cubeVAO);
+        glGenBuffers(1, &cubeVBO);
+        // fill buffer
+        glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
+        glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+        // link vertex attributes
+        glBindVertexArray(cubeVAO);
+        glEnableVertexAttribArray(0);
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
+        glEnableVertexAttribArray(1);
+        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
+        glEnableVertexAttribArray(2);
+        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        glBindVertexArray(0);
+    }
+    // render Cube
+    glBindVertexArray(cubeVAO);
+    glDrawArrays(GL_TRIANGLES, 0, 36);
+    glBindVertexArray(0);
+}
+
+// renderQuad() renders a 1x1 XY quad in NDC
+// -----------------------------------------
+unsigned int quadVAO = 0;
+unsigned int quadVBO;
+void renderQuad()
 {
     if (quadVAO == 0)
     {
-        GLfloat quadVertices[] = {
+        float quadVertices[] = {
-            // Positions        // Texture Coords
+            // positions        // texture Coords
             -1.0f,  1.0f, 0.0f, 0.0f, 1.0f,
             -1.0f, -1.0f, 0.0f, 0.0f, 0.0f,
              1.0f,  1.0f, 0.0f, 1.0f, 1.0f,
              1.0f, -1.0f, 0.0f, 1.0f, 0.0f,
         };
-        // Setup plane VAO
+        // setup plane VAO
         glGenVertexArrays(1, &quadVAO);
         glGenBuffers(1, &quadVBO);
         glBindVertexArray(quadVAO);
         glBindBuffer(GL_ARRAY_BUFFER, quadVBO);
         glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
         glEnableVertexAttribArray(0);
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)0);
         glEnableVertexAttribArray(1);
-        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
+        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
     }
     glBindVertexArray(quadVAO);
     glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
     glBindVertexArray(0);
 }
 
-// RenderCube() Renders a 1x1 3D cube in NDC.
+// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
-GLuint cubeVAO = 0;
+// ---------------------------------------------------------------------------------------------------------
-GLuint cubeVBO = 0;
+void processInput(GLFWwindow *window)
-void RenderCube()
 {
-    // Initialize (if necessary)
+    if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
-    if (cubeVAO == 0)
+        glfwSetWindowShouldClose(window, true);
-    {
-        GLfloat vertices[] = {
-            // Back face
-            -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // Bottom-left
-            0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,  // top-right
-            -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,  // bottom-left
-            -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f,// top-left
-            // Front face
-            -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
-            0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f,  // bottom-right
-            0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,  // top-right
-            0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
-            -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f,  // top-left
-            -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,  // bottom-left
-            // Left face
-            -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-            -0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-left
-            -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,  // bottom-left
-            -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-            -0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f,  // bottom-right
-            -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-            // Right face
-            0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
-            0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,  // bottom-right
-            0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,  // top-left
-            0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-left
-            // Bottom face
-            -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f, // top-left
-            0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,// bottom-left
-            0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, // bottom-left
-            -0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-            -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
-            // Top face
-            -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-            0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, // top-right
-            0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-            -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-            -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f // bottom-left
-        };
-        glGenVertexArrays(1, &cubeVAO);
-        glGenBuffers(1, &cubeVBO);
-        // Fill buffer
-        glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
-        glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
-        // Link vertex attributes
-        glBindVertexArray(cubeVAO);
-        glEnableVertexAttribArray(0);
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
-        glEnableVertexAttribArray(1);
-        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
-        glEnableVertexAttribArray(2);
-        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
-        glBindVertexArray(0);
-    }
-    // Render Cube
-    glBindVertexArray(cubeVAO);
-    glDrawArrays(GL_TRIANGLES, 0, 36);
-    glBindVertexArray(0);
-}
 
-// This function loads a texture from file. Note: texture loading functions like these are usually
+    float cameraSpeed = 2.5 * deltaTime;
-// managed by a 'Resource Manager' that manages all resources (like textures, models, audio).
+    if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS)
-// For learning purposes we'll just define it as a utility function.
-GLuint loadTexture(GLchar const * path)
-{
-    // Generate texture ID and load texture data
-    GLuint textureID;
-    glGenTextures(1, &textureID);
-    int width, height;
-    unsigned char* image = SOIL_load_image(path, &width, &height, 0, SOIL_LOAD_RGB);
-    // Assign texture to ID
-    glBindTexture(GL_TEXTURE_2D, textureID);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
-    glGenerateMipmap(GL_TEXTURE_2D);
-
-    // Parameters
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-    glBindTexture(GL_TEXTURE_2D, 0);
-    SOIL_free_image_data(image);
-    return textureID;
-
-}
-
-bool keys[1024];
-bool keysPressed[1024];
-// Moves/alters the camera positions based on user input
-void Do_Movement()
-{
-    // Camera controls
-    if (keys[GLFW_KEY_W])
         camera.ProcessKeyboard(FORWARD, deltaTime);
-    if (keys[GLFW_KEY_S])
+    if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS)
         camera.ProcessKeyboard(BACKWARD, deltaTime);
-    if (keys[GLFW_KEY_A])
+    if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS)
         camera.ProcessKeyboard(LEFT, deltaTime);
-    if (keys[GLFW_KEY_D])
+    if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS)
         camera.ProcessKeyboard(RIGHT, deltaTime);
-
-    if (keys[GLFW_KEY_SPACE] && !keysPressed[GLFW_KEY_SPACE])
-    {
-        shadows = !shadows;
-        keysPressed[GLFW_KEY_SPACE] = true;
-    }
 }
 
-GLfloat lastX = 400, lastY = 300;
+// glfw: whenever the window size changed (by OS or user resize) this callback function executes
-bool firstMouse = true;
+// ---------------------------------------------------------------------------------------------
-// Is called whenever a key is pressed/released via GLFW
+void framebuffer_size_callback(GLFWwindow* window, int width, int height)
-void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
 {
-    if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
+    // make sure the viewport matches the new window dimensions; note that width and 
-        glfwSetWindowShouldClose(window, GL_TRUE);
+    // height will be significantly larger than specified on retina displays.
-
+    glViewport(0, 0, width, height);
-    if (key >= 0 && key <= 1024)
-    {
-        if (action == GLFW_PRESS)
-            keys[key] = true;
-        else if (action == GLFW_RELEASE)
-        {
-            keys[key] = false;
-            keysPressed[key] = false;
-        }
-    }
 }
 
+
+// glfw: whenever the mouse moves, this callback is called
+// -------------------------------------------------------
 void mouse_callback(GLFWwindow* window, double xpos, double ypos)
 {
     if (firstMouse)
@@ -420,8 +408,8 @@ void mouse_callback(GLFWwindow* window, double xpos, double ypos)
         firstMouse = false;
     }
 
-    GLfloat xoffset = xpos - lastX;
+    float xoffset = xpos - lastX;
-    GLfloat yoffset = lastY - ypos;
+    float yoffset = lastY - ypos; // reversed since y-coordinates go from bottom to top
 
     lastX = xpos;
     lastY = ypos;
@@ -429,7 +417,48 @@ void mouse_callback(GLFWwindow* window, double xpos, double ypos)
     camera.ProcessMouseMovement(xoffset, yoffset);
 }
 
+// glfw: whenever the mouse scroll wheel scrolls, this callback is called
+// ----------------------------------------------------------------------
 void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
 {
     camera.ProcessMouseScroll(yoffset);
 }
+
+// utility function for loading a 2D texture from file
+// ---------------------------------------------------
+unsigned int loadTexture(char const * path)
+{
+    unsigned int textureID;
+    glGenTextures(1, &textureID);
+
+    int width, height, nrComponents;
+    unsigned char *data = stbi_load(path, &width, &height, &nrComponents, 0);
+    if (data)
+    {
+        GLenum format;
+        if (nrComponents == 1)
+            format = GL_RED;
+        else if (nrComponents == 3)
+            format = GL_RGB;
+        else if (nrComponents == 4)
+            format = GL_RGBA;
+
+        glBindTexture(GL_TEXTURE_2D, textureID);
+        glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
+        glGenerateMipmap(GL_TEXTURE_2D);
+
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT); // for this tutorial: use GL_CLAMP_TO_EDGE to prevent semi-transparent borders. Due to interpolation it takes texels from next repeat 
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+        stbi_image_free(data);
+    }
+    else
+    {
+        std::cout << "Texture failed to load at path: " << path << std::endl;
+        stbi_image_free(data);
+    }
+
+    return textureID;
+}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/shadow_mapping_depth.fs

@@ -1,6 +0,0 @@
-#version 330 core
-
-void main()
-{             
-    // gl_FragDepth = gl_FragCoord.z;
-}

src/5.advanced_lighting/3.1.2.shadow_mapping_base/shadow_mapping_depth.vs

@@ -1,10 +0,0 @@
-#version 330 core
-layout (location = 0) in vec3 position;
-
-uniform mat4 lightSpaceMatrix;
-uniform mat4 model;
-
-void main()
-{
-    gl_Position = lightSpaceMatrix * model * vec4(position, 1.0f);
-}

src/5.advanced_lighting/3.1.3.shadow_mapping/3.1.3.shadow_mapping.fs

@@ -14,23 +14,21 @@ uniform sampler2D shadowMap;
 uniform vec3 lightPos;
 uniform vec3 viewPos;
 
-uniform bool shadows;
-
 float ShadowCalculation(vec4 fragPosLightSpace)
 {
     // perform perspective divide
     vec3 projCoords = fragPosLightSpace.xyz / fragPosLightSpace.w;
-    // Transform to [0,1] range
+    // transform to [0,1] range
     projCoords = projCoords * 0.5 + 0.5;
-    // Get closest depth value from light's perspective (using [0,1] range fragPosLight as coords)
+    // get closest depth value from light's perspective (using [0,1] range fragPosLight as coords)
     float closestDepth = texture(shadowMap, projCoords.xy).r; 
-    // Get depth of current fragment from light's perspective
+    // get depth of current fragment from light's perspective
     float currentDepth = projCoords.z;
-    // Calculate bias (based on depth map resolution and slope)
+    // calculate bias (based on depth map resolution and slope)
     vec3 normal = normalize(fs_in.Normal);
     vec3 lightDir = normalize(lightPos - fs_in.FragPos);
     float bias = max(0.05 * (1.0 - dot(normal, lightDir)), 0.005);
-    // Check whether current frag pos is in shadow
+    // check whether current frag pos is in shadow
     // float shadow = currentDepth - bias > closestDepth  ? 1.0 : 0.0;
     // PCF
     float shadow = 0.0;
@@ -45,7 +43,7 @@ float ShadowCalculation(vec4 fragPosLightSpace)
     }
     shadow /= 9.0;
     
-    // Keep the shadow at 0.0 when outside the far_plane region of the light's frustum.
+    // keep the shadow at 0.0 when outside the far_plane region of the light's frustum.
     if(projCoords.z > 1.0)
         shadow = 0.0;
         
@@ -57,22 +55,22 @@ void main()
     vec3 color = texture(diffuseTexture, fs_in.TexCoords).rgb;
     vec3 normal = normalize(fs_in.Normal);
     vec3 lightColor = vec3(0.3);
-    // Ambient
+    // ambient
     vec3 ambient = 0.3 * color;
-    // Diffuse
+    // diffuse
     vec3 lightDir = normalize(lightPos - fs_in.FragPos);
     float diff = max(dot(lightDir, normal), 0.0);
     vec3 diffuse = diff * lightColor;
-    // Specular
+    // specular
     vec3 viewDir = normalize(viewPos - fs_in.FragPos);
     vec3 reflectDir = reflect(-lightDir, normal);
     float spec = 0.0;
     vec3 halfwayDir = normalize(lightDir + viewDir);  
     spec = pow(max(dot(normal, halfwayDir), 0.0), 64.0);
     vec3 specular = spec * lightColor;    
-    // Calculate shadow
+    // calculate shadow
-    float shadow = shadows ? ShadowCalculation(fs_in.FragPosLightSpace) : 0.0;                      
+    float shadow = ShadowCalculation(fs_in.FragPosLightSpace);                      
     vec3 lighting = (ambient + (1.0 - shadow) * (diffuse + specular)) * color;    
     
-    FragColor = vec4(lighting, 1.0f);
+    FragColor = vec4(lighting, 1.0);
 }

src/5.advanced_lighting/3.1.3.shadow_mapping/3.1.3.shadow_mapping.vs

@@ -0,0 +1,27 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aNormal;
+layout (location = 2) in vec2 aTexCoords;
+
+out vec2 TexCoords;
+
+out VS_OUT {
+    vec3 FragPos;
+    vec3 Normal;
+    vec2 TexCoords;
+    vec4 FragPosLightSpace;
+} vs_out;
+
+uniform mat4 projection;
+uniform mat4 view;
+uniform mat4 model;
+uniform mat4 lightSpaceMatrix;
+
+void main()
+{
+    vs_out.FragPos = vec3(model * vec4(aPos, 1.0));
+    vs_out.Normal = transpose(inverse(mat3(model))) * aNormal;
+    vs_out.TexCoords = aTexCoords;
+    vs_out.FragPosLightSpace = lightSpaceMatrix * vec4(vs_out.FragPos, 1.0);
+    gl_Position = projection * view * model * vec4(aPos, 1.0f);
+}

src/5.advanced_lighting/3.1.3.shadow_mapping/debug_quad.vs

@@ -1,11 +0,0 @@
-#version 330 core
-layout (location = 0) in vec3 position;
-layout (location = 1) in vec2 texCoords;
-
-out vec2 TexCoords;
-
-void main()
-{
-    gl_Position = vec4(position, 1.0f);
-    TexCoords = texCoords;
-}

src/5.advanced_lighting/3.1.3.shadow_mapping/debug_quad_depth.fs

@@ -1,20 +0,0 @@
-#version 330 core
-out vec4 color;
-in vec2 TexCoords;
-
-uniform sampler2D depthMap;
-uniform float near_plane;
-uniform float far_plane;
-
-float LinearizeDepth(float depth)
-{
-    float z = depth * 2.0 - 1.0; // Back to NDC 
-    return (2.0 * near_plane * far_plane) / (far_plane + near_plane - z * (far_plane - near_plane));	
-}
-
-void main()
-{             
-    float depthValue = texture(depthMap, TexCoords).r;
-    // color = vec4(vec3(LinearizeDepth(depthValue) / far_plane), 1.0); // perspective
-    color = vec4(vec3(depthValue), 1.0); // orthographic
-}

src/5.advanced_lighting/3.1.3.shadow_mapping/shadow_mapping.cpp

@@ -1,131 +1,128 @@
-// GLEW
+#include <glad/glad.h>
-#define GLEW_STATIC
-#include <GL/glew.h>
-
-// GLFW
 #include <GLFW/glfw3.h>
+#include <stb_image.h>
 
-// GL includes
-#include <learnopengl/shader.h>
-#include <learnopengl/camera.h>
-
-// GLM Mathemtics
 #include <glm/glm.hpp>
 #include <glm/gtc/matrix_transform.hpp>
 #include <glm/gtc/type_ptr.hpp>
 
-// Other Libs
-#include <SOIL.h>
 #include <learnopengl/filesystem.h>
+#include <learnopengl/shader.h>
+#include <learnopengl/camera.h>
+#include <learnopengl/model.h>
 
-// Properties
+#include <iostream>
-const GLuint SCR_WIDTH = 800, SCR_HEIGHT = 600;
 
-// Function prototypes
+void framebuffer_size_callback(GLFWwindow* window, int width, int height);
-void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);
-void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
 void mouse_callback(GLFWwindow* window, double xpos, double ypos);
-void Do_Movement();
+void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
-GLuint loadTexture(GLchar const * path);
+void processInput(GLFWwindow *window);
-void RenderScene(Shader &shader);
+unsigned int loadTexture(const char *path);
-void RenderCube();
+void renderScene(const Shader &shader);
-void RenderQuad();
+void renderCube();
+void renderQuad();
 
-// Camera
+// settings
+const unsigned int SCR_WIDTH = 1280;
+const unsigned int SCR_HEIGHT = 720;
+
+// camera
 Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
+float lastX = (float)SCR_WIDTH / 2.0;
+float lastY = (float)SCR_HEIGHT / 2.0;
+bool firstMouse = true;
 
-// Delta
+// timing
-GLfloat deltaTime = 0.0f;
+float deltaTime = 0.0f;
-GLfloat lastFrame = 0.0f;
+float lastFrame = 0.0f;
 
-// Options
+// meshes
-GLboolean shadows = true;
+unsigned int planeVAO;
 
-// Global variables
-GLuint woodTexture;
-GLuint planeVAO;
-
-// The MAIN function, from here we start our application and run our Game loop
 int main()
 {
-    // Init GLFW
+    // glfw: initialize and configure
+    // ------------------------------
     glfwInit();
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
     glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
-    glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
 
-    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", nullptr, nullptr); // Windowed
+    // glfw window creation
+    // --------------------
+    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
     glfwMakeContextCurrent(window);
-
+    if (window == NULL)
-    // Set the required callback functions
+    {
-    glfwSetKeyCallback(window, key_callback);
+        std::cout << "Failed to create GLFW window" << std::endl;
+        glfwTerminate();
+        return -1;
+    }
+    glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
     glfwSetCursorPosCallback(window, mouse_callback);
     glfwSetScrollCallback(window, scroll_callback);
 
-    // Options
+    // tell GLFW to capture our mouse
     glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
 
-    // Initialize GLEW to setup the OpenGL Function pointers
+    // glad: load all OpenGL function pointers
-    glewExperimental = GL_TRUE;
+    // ---------------------------------------
-    glewInit();
+    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
+    {
+        std::cout << "Failed to initialize GLAD" << std::endl;
+        return -1;
+    }
 
-    // Define the viewport dimensions
+    // configure global opengl state
-    glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+    // -----------------------------
-
-    // Setup some OpenGL options
     glEnable(GL_DEPTH_TEST);
 
-    // Setup and compile our shaders
+    // build and compile shaders
-    Shader shader("shadow_mapping.vs", "shadow_mapping.frag");
+    // -------------------------
-    Shader simpleDepthShader("shadow_mapping_depth.vs", "shadow_mapping_depth.frag");
+    Shader shader("3.1.3.shadow_mapping.vs", "3.1.3.shadow_mapping.fs");
-    Shader debugDepthQuad("debug_quad.vs", "debug_quad_depth.frag");
+    Shader simpleDepthShader("3.1.1.shadow_mapping_depth.vs", "3.1.1.shadow_mapping_depth.fs");
+    Shader debugDepthQuad("3.1.1.debug_quad.vs", "3.1.1.debug_quad_depth.fs");
 
-    // Set texture samples
+    // set up vertex data (and buffer(s)) and configure vertex attributes
-    shader.Use();
+    // ------------------------------------------------------------------
-    glUniform1i(glGetUniformLocation(shader.Program, "diffuseTexture"), 0);
+    float planeVertices[] = {
-    glUniform1i(glGetUniformLocation(shader.Program, "shadowMap"), 1);
+        // positions            // normals         // texcoords
+         25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,  25.0f,  0.0f,
+        -25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,   0.0f,  0.0f,
+        -25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,   0.0f, 25.0f,
 
-    GLfloat planeVertices[] = {
-        // Positions            // Normals           // Texture Coords
          25.0f, -0.5f,  25.0f,  0.0f, 1.0f, 0.0f,  25.0f,  0.0f,
         -25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,   0.0f, 25.0f,
-        -25.0f, -0.5f,  25.0f,  0.0f,  1.0f,  0.0f,  0.0f,  0.0f,
+         25.0f, -0.5f, -25.0f,  0.0f, 1.0f, 0.0f,  25.0f, 25.0f
-
-         25.0f, -0.5f,  25.0f,  0.0f,  1.0f,  0.0f,  25.0f, 0.0f,
-         25.0f, -0.5f, -25.0f,  0.0f,  1.0f,  0.0f,  25.0f, 25.0f,
-        -25.0f, -0.5f, -25.0f,  0.0f,  1.0f,  0.0f,  0.0f,  25.0f
     };
-    // Setup plane VAO
+    // plane VAO
-    GLuint planeVBO;
+    unsigned int planeVBO;
     glGenVertexArrays(1, &planeVAO);
     glGenBuffers(1, &planeVBO);
     glBindVertexArray(planeVAO);
     glBindBuffer(GL_ARRAY_BUFFER, planeVBO);
-    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), &planeVertices, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), planeVertices, GL_STATIC_DRAW);
     glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
     glEnableVertexAttribArray(1);
-    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
     glEnableVertexAttribArray(2);
-    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
     glBindVertexArray(0);
 
-    // Light source
+    // load textures
-    glm::vec3 lightPos(-2.0f, 4.0f, -1.0f);
+    // -------------
+    unsigned int woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
 
-    // Load textures
+    // configure depth map FBO
-    woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
+    // -----------------------
-
+    const unsigned int SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
-    // Configure depth map FBO
+    unsigned int depthMapFBO;
-    const GLuint SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
-    GLuint depthMapFBO;
     glGenFramebuffers(1, &depthMapFBO);
-    // - Create depth texture
+    // create depth texture
-    GLuint depthMap;
+    unsigned int depthMap;
     glGenTextures(1, &depthMap);
     glBindTexture(GL_TEXTURE_2D, depthMap);
-
     glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, SHADOW_WIDTH, SHADOW_HEIGHT, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ -133,284 +130,283 @@ int main()
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
     GLfloat borderColor[] = { 1.0, 1.0, 1.0, 1.0 };
     glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
-
+    // attach depth texture as FBO's depth buffer
     glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
     glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthMap, 0);
     glDrawBuffer(GL_NONE);
     glReadBuffer(GL_NONE);
     glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
-    glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
 
-    // Game loop
+    // shader configuration
+    // --------------------
+    shader.use();
+    shader.setInt("diffuseTexture", 0);
+    shader.setInt("shadowMap", 1);
+    debugDepthQuad.use();
+    debugDepthQuad.setInt("depthMap", 0);
+
+    // lighting info
+    // -------------
+    glm::vec3 lightPos(-2.0f, 4.0f, -1.0f);
+
+    // render loop
+    // -----------
     while (!glfwWindowShouldClose(window))
     {
-        // Set frame time
+        // per-frame time logic
-        GLfloat currentFrame = glfwGetTime();
+        // --------------------
+        float currentFrame = glfwGetTime();
         deltaTime = currentFrame - lastFrame;
         lastFrame = currentFrame;
 
-        // Check and call events
+        // input
-        glfwPollEvents();
+        // -----
-        Do_Movement();
+        processInput(window);
 
-        // Change light position over time
+        // change light position over time
-        lightPos.z = cos(glfwGetTime()) * 2.0f;
+        //lightPos.x = sin(glfwGetTime()) * 3.0f;
+        //lightPos.z = cos(glfwGetTime()) * 2.0f;
+        //lightPos.y = 5.0 + cos(glfwGetTime()) * 1.0f;
 
-        // 1. Render depth of scene to texture (from light's perspective)
+        // render
-        // - Get light projection/view matrix.
+        // ------
+        glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+        // 1. render depth of scene to texture (from light's perspective)
+        // --------------------------------------------------------------
         glm::mat4 lightProjection, lightView;
         glm::mat4 lightSpaceMatrix;
-        GLfloat near_plane = 1.0f, far_plane = 7.5f;
+        float near_plane = 1.0f, far_plane = 7.5f;
+        //lightProjection = glm::perspective(glm::radians(45.0f), (GLfloat)SHADOW_WIDTH / (GLfloat)SHADOW_HEIGHT, near_plane, far_plane); // note that if you use a perspective projection matrix you'll have to change the light position as the current light position isn't enough to reflect the whole scene
         lightProjection = glm::ortho(-10.0f, 10.0f, -10.0f, 10.0f, near_plane, far_plane);
-        //lightProjection = glm::perspective(45.0f, (GLfloat)SHADOW_WIDTH / (GLfloat)SHADOW_HEIGHT, near_plane, far_plane); // Note that if you use a perspective projection matrix you'll have to change the light position as the current light position isn't enough to reflect the whole scene.
         lightView = glm::lookAt(lightPos, glm::vec3(0.0f), glm::vec3(0.0, 1.0, 0.0));
         lightSpaceMatrix = lightProjection * lightView;
-        // - now render scene from light's point of view
+        // render scene from light's point of view
-        simpleDepthShader.Use();
+        simpleDepthShader.use();
-        glUniformMatrix4fv(glGetUniformLocation(simpleDepthShader.Program, "lightSpaceMatrix"), 1, GL_FALSE, glm::value_ptr(lightSpaceMatrix));
+        simpleDepthShader.setMat4("lightSpaceMatrix", lightSpaceMatrix);
+
         glViewport(0, 0, SHADOW_WIDTH, SHADOW_HEIGHT);
         glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
             glClear(GL_DEPTH_BUFFER_BIT);
-            RenderScene(simpleDepthShader);
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, woodTexture);
+            renderScene(simpleDepthShader);
         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
-        // 2. Render scene as normal
+        // reset viewport
         glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-        shader.Use();
+
+        // 2. render scene as normal using the generated depth/shadow map  
+        // --------------------------------------------------------------
+        glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+        shader.use();
         glm::mat4 projection = glm::perspective(camera.Zoom, (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
         glm::mat4 view = camera.GetViewMatrix();
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "projection"), 1, GL_FALSE, glm::value_ptr(projection));
+        shader.setMat4("projection", projection);
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "view"), 1, GL_FALSE, glm::value_ptr(view));
+        shader.setMat4("view", view);
-        // Set light uniforms
+        // set light uniforms
-        glUniform3fv(glGetUniformLocation(shader.Program, "lightPos"), 1, &lightPos[0]);
+        shader.setVec3("viewPos", camera.Position);
-        glUniform3fv(glGetUniformLocation(shader.Program, "viewPos"), 1, &camera.Position[0]);
+        shader.setVec3("lightPos", lightPos);
-        glUniformMatrix4fv(glGetUniformLocation(shader.Program, "lightSpaceMatrix"), 1, GL_FALSE, glm::value_ptr(lightSpaceMatrix));
+        shader.setMat4("lightSpaceMatrix", lightSpaceMatrix);
-        // Enable/Disable shadows by pressing 'SPACE'
-        glUniform1i(glGetUniformLocation(shader.Program, "shadows"), shadows);
         glActiveTexture(GL_TEXTURE0);
         glBindTexture(GL_TEXTURE_2D, woodTexture);
         glActiveTexture(GL_TEXTURE1);
         glBindTexture(GL_TEXTURE_2D, depthMap);
-        RenderScene(shader);
+        renderScene(shader);
 
-        // 3. DEBUG: visualize depth map by rendering it to plane
+        // render Depth map to quad for visual debugging
-        debugDepthQuad.Use();
+        // ---------------------------------------------
-        glUniform1f(glGetUniformLocation(debugDepthQuad.Program, "near_plane"), near_plane);
+        debugDepthQuad.use();
-        glUniform1f(glGetUniformLocation(debugDepthQuad.Program, "far_plane"), far_plane);
+        debugDepthQuad.setFloat("near_plane", near_plane);
+        debugDepthQuad.setFloat("far_plane", far_plane);
         glActiveTexture(GL_TEXTURE0);
         glBindTexture(GL_TEXTURE_2D, depthMap);
-        //RenderQuad(); // uncomment this line to see depth map
+        //renderQuad();
 
-
+        // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
-        // Swap the buffers
+        // -------------------------------------------------------------------------------
         glfwSwapBuffers(window);
+        glfwPollEvents();
     }
 
+    // optional: de-allocate all resources once they've outlived their purpose:
+    // ------------------------------------------------------------------------
+    glDeleteVertexArrays(1, &planeVAO);
+    glDeleteBuffers(1, &planeVBO);
+
     glfwTerminate();
     return 0;
 }
 
-void RenderScene(Shader &shader)
+// renders the 3D scene
+// --------------------
+void renderScene(const Shader &shader)
 {
-    // Floor
+    // floor
     glm::mat4 model;
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    shader.setMat4("model", model);
     glBindVertexArray(planeVAO);
     glDrawArrays(GL_TRIANGLES, 0, 6);
-    glBindVertexArray(0);
+    // cubes
-    // Cubes
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(0.0f, 1.5f, 0.0));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    model = glm::scale(model, glm::vec3(0.5f));
-    RenderCube();
+    shader.setMat4("model", model);
+    renderCube();
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(2.0f, 0.0f, 1.0));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    model = glm::scale(model, glm::vec3(0.5f));
-    RenderCube();
+    shader.setMat4("model", model);
+    renderCube();
     model = glm::mat4();
     model = glm::translate(model, glm::vec3(-1.0f, 0.0f, 2.0));
-    model = glm::rotate(model, 60.0f, glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
+    model = glm::rotate(model, glm::radians(60.0f), glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
-    model = glm::scale(model, glm::vec3(0.5));
+    model = glm::scale(model, glm::vec3(0.25));
-    glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
+    shader.setMat4("model", model);
-    RenderCube();
+    renderCube();
 }
 
 
-// RenderQuad() Renders a 1x1 quad in NDC, best used for framebuffer color targets
+// renderCube() renders a 1x1 3D cube in NDC.
-// and post-processing effects.
+// -------------------------------------------------
-GLuint quadVAO = 0;
+unsigned int cubeVAO = 0;
-GLuint quadVBO;
+unsigned int cubeVBO = 0;
-void RenderQuad()
+void renderCube()
+{
+    // initialize (if necessary)
+    if (cubeVAO == 0)
+    {
+        float vertices[] = {
+            // back face
+            -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
+             1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 1.0f, // top-right
+             1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 0.0f, // bottom-right         
+             1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 1.0f, 1.0f, // top-right
+            -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
+            -1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 0.0f, 1.0f, // top-left
+            // front face
+            -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 0.0f, // bottom-left
+             1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 0.0f, // bottom-right
+             1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 1.0f, // top-right
+             1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 1.0f, 1.0f, // top-right
+            -1.0f,  1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 1.0f, // top-left
+            -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,  1.0f, 0.0f, 0.0f, // bottom-left
+            // left face
+            -1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-right
+            -1.0f,  1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 1.0f, // top-left
+            -1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-left
+            -1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-left
+            -1.0f, -1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 0.0f, 0.0f, // bottom-right
+            -1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-right
+            // right face
+             1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-left
+             1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-right
+             1.0f,  1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 1.0f, // top-right         
+             1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 1.0f, // bottom-right
+             1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f, 0.0f, // top-left
+             1.0f, -1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 0.0f, 0.0f, // bottom-left     
+            // bottom face
+            -1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 1.0f, // top-right
+             1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 1.0f, // top-left
+             1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 0.0f, // bottom-left
+             1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 1.0f, 0.0f, // bottom-left
+            -1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 0.0f, // bottom-right
+            -1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f, 0.0f, 1.0f, // top-right
+            // top face
+            -1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 1.0f, // top-left
+             1.0f,  1.0f , 1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 0.0f, // bottom-right
+             1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 1.0f, // top-right     
+             1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f, 1.0f, 0.0f, // bottom-right
+            -1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 1.0f, // top-left
+            -1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f, 0.0f, 0.0f  // bottom-left        
+        };
+        glGenVertexArrays(1, &cubeVAO);
+        glGenBuffers(1, &cubeVBO);
+        // fill buffer
+        glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
+        glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+        // link vertex attributes
+        glBindVertexArray(cubeVAO);
+        glEnableVertexAttribArray(0);
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
+        glEnableVertexAttribArray(1);
+        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
+        glEnableVertexAttribArray(2);
+        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        glBindVertexArray(0);
+    }
+    // render Cube
+    glBindVertexArray(cubeVAO);
+    glDrawArrays(GL_TRIANGLES, 0, 36);
+    glBindVertexArray(0);
+}
+
+// renderQuad() renders a 1x1 XY quad in NDC
+// -----------------------------------------
+unsigned int quadVAO = 0;
+unsigned int quadVBO;
+void renderQuad()
 {
     if (quadVAO == 0)
     {
-        GLfloat quadVertices[] = {
+        float quadVertices[] = {
-            // Positions        // Texture Coords
+            // positions        // texture Coords
             -1.0f,  1.0f, 0.0f, 0.0f, 1.0f,
             -1.0f, -1.0f, 0.0f, 0.0f, 0.0f,
              1.0f,  1.0f, 0.0f, 1.0f, 1.0f,
              1.0f, -1.0f, 0.0f, 1.0f, 0.0f,
         };
-        // Setup plane VAO
+        // setup plane VAO
         glGenVertexArrays(1, &quadVAO);
         glGenBuffers(1, &quadVBO);
         glBindVertexArray(quadVAO);
         glBindBuffer(GL_ARRAY_BUFFER, quadVBO);
         glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
         glEnableVertexAttribArray(0);
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)0);
         glEnableVertexAttribArray(1);
-        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
+        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
     }
     glBindVertexArray(quadVAO);
     glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
     glBindVertexArray(0);
 }
 
-// RenderCube() Renders a 1x1 3D cube in NDC.
+// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
-GLuint cubeVAO = 0;
+// ---------------------------------------------------------------------------------------------------------
-GLuint cubeVBO = 0;
+void processInput(GLFWwindow *window)
-void RenderCube()
 {
-    // Initialize (if necessary)
+    if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
-    if (cubeVAO == 0)
+        glfwSetWindowShouldClose(window, true);
-    {
-        GLfloat vertices[] = {
-            // Back face
-            -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // Bottom-left
-            0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f,  // top-right
-            -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f,  // bottom-left
-            -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f,// top-left
-            // Front face
-            -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
-            0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f,  // bottom-right
-            0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,  // top-right
-            0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
-            -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f,  // top-left
-            -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f,  // bottom-left
-            // Left face
-            -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-            -0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-left
-            -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f,  // bottom-left
-            -0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-            -0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f,  // bottom-right
-            -0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-            // Right face
-            0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
-            0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,  // bottom-right
-            0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,  // top-left
-            0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-left
-            // Bottom face
-            -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
-            0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f, // top-left
-            0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,// bottom-left
-            0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, // bottom-left
-            -0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-            -0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
-            // Top face
-            -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-            0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-            0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, // top-right
-            0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-            -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-            -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f // bottom-left
-        };
-        glGenVertexArrays(1, &cubeVAO);
-        glGenBuffers(1, &cubeVBO);
-        // Fill buffer
-        glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
-        glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
-        // Link vertex attributes
-        glBindVertexArray(cubeVAO);
-        glEnableVertexAttribArray(0);
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
-        glEnableVertexAttribArray(1);
-        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
-        glEnableVertexAttribArray(2);
-        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
-        glBindVertexArray(0);
-    }
-    // Render Cube
-    glBindVertexArray(cubeVAO);
-    glDrawArrays(GL_TRIANGLES, 0, 36);
-    glBindVertexArray(0);
-}
 
-// This function loads a texture from file. Note: texture loading functions like these are usually
+    float cameraSpeed = 2.5 * deltaTime;
-// managed by a 'Resource Manager' that manages all resources (like textures, models, audio).
+    if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS)
-// For learning purposes we'll just define it as a utility function.
-GLuint loadTexture(GLchar const * path)
-{
-    // Generate texture ID and load texture data
-    GLuint textureID;
-    glGenTextures(1, &textureID);
-    int width, height;
-    unsigned char* image = SOIL_load_image(path, &width, &height, 0, SOIL_LOAD_RGB);
-    // Assign texture to ID
-    glBindTexture(GL_TEXTURE_2D, textureID);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
-    glGenerateMipmap(GL_TEXTURE_2D);
-
-    // Parameters
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-    glBindTexture(GL_TEXTURE_2D, 0);
-    SOIL_free_image_data(image);
-    return textureID;
-
-}
-
-bool keys[1024];
-bool keysPressed[1024];
-// Moves/alters the camera positions based on user input
-void Do_Movement()
-{
-    // Camera controls
-    if (keys[GLFW_KEY_W])
         camera.ProcessKeyboard(FORWARD, deltaTime);
-    if (keys[GLFW_KEY_S])
+    if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS)
         camera.ProcessKeyboard(BACKWARD, deltaTime);
-    if (keys[GLFW_KEY_A])
+    if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS)
         camera.ProcessKeyboard(LEFT, deltaTime);
-    if (keys[GLFW_KEY_D])
+    if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS)
         camera.ProcessKeyboard(RIGHT, deltaTime);
-
-    if (keys[GLFW_KEY_SPACE] && !keysPressed[GLFW_KEY_SPACE])
-    {
-        shadows = !shadows;
-        keysPressed[GLFW_KEY_SPACE] = true;
-    }
 }
 
-GLfloat lastX = 400, lastY = 300;
+// glfw: whenever the window size changed (by OS or user resize) this callback function executes
-bool firstMouse = true;
+// ---------------------------------------------------------------------------------------------
-// Is called whenever a key is pressed/released via GLFW
+void framebuffer_size_callback(GLFWwindow* window, int width, int height)
-void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
 {
-    if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
+    // make sure the viewport matches the new window dimensions; note that width and 
-        glfwSetWindowShouldClose(window, GL_TRUE);
+    // height will be significantly larger than specified on retina displays.
-
+    glViewport(0, 0, width, height);
-    if (key >= 0 && key <= 1024)
-    {
-        if (action == GLFW_PRESS)
-            keys[key] = true;
-        else if (action == GLFW_RELEASE)
-        {
-            keys[key] = false;
-            keysPressed[key] = false;
-        }
-    }
 }
 
+
+// glfw: whenever the mouse moves, this callback is called
+// -------------------------------------------------------
 void mouse_callback(GLFWwindow* window, double xpos, double ypos)
 {
     if (firstMouse)
@@ -420,8 +416,8 @@ void mouse_callback(GLFWwindow* window, double xpos, double ypos)
         firstMouse = false;
     }
 
-    GLfloat xoffset = xpos - lastX;
+    float xoffset = xpos - lastX;
-    GLfloat yoffset = lastY - ypos;
+    float yoffset = lastY - ypos; // reversed since y-coordinates go from bottom to top
 
     lastX = xpos;
     lastY = ypos;
@@ -429,7 +425,48 @@ void mouse_callback(GLFWwindow* window, double xpos, double ypos)
     camera.ProcessMouseMovement(xoffset, yoffset);
 }
 
+// glfw: whenever the mouse scroll wheel scrolls, this callback is called
+// ----------------------------------------------------------------------
 void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
 {
     camera.ProcessMouseScroll(yoffset);
 }
+
+// utility function for loading a 2D texture from file
+// ---------------------------------------------------
+unsigned int loadTexture(char const * path)
+{
+    unsigned int textureID;
+    glGenTextures(1, &textureID);
+
+    int width, height, nrComponents;
+    unsigned char *data = stbi_load(path, &width, &height, &nrComponents, 0);
+    if (data)
+    {
+        GLenum format;
+        if (nrComponents == 1)
+            format = GL_RED;
+        else if (nrComponents == 3)
+            format = GL_RGB;
+        else if (nrComponents == 4)
+            format = GL_RGBA;
+
+        glBindTexture(GL_TEXTURE_2D, textureID);
+        glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
+        glGenerateMipmap(GL_TEXTURE_2D);
+
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT); // for this tutorial: use GL_CLAMP_TO_EDGE to prevent semi-transparent borders. Due to interpolation it takes texels from next repeat 
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+        stbi_image_free(data);
+    }
+    else
+    {
+        std::cout << "Texture failed to load at path: " << path << std::endl;
+        stbi_image_free(data);
+    }
+
+    return textureID;
+}

src/5.advanced_lighting/3.1.3.shadow_mapping/shadow_mapping.vs

@@ -1,27 +0,0 @@
-#version 330 core
-layout (location = 0) in vec3 position;
-layout (location = 1) in vec3 normal;
-layout (location = 2) in vec2 texCoords;
-
-out vec2 TexCoords;
-
-out VS_OUT {
-    vec3 FragPos;
-    vec3 Normal;
-    vec2 TexCoords;
-    vec4 FragPosLightSpace;
-} vs_out;
-
-uniform mat4 projection;
-uniform mat4 view;
-uniform mat4 model;
-uniform mat4 lightSpaceMatrix;
-
-void main()
-{
-    gl_Position = projection * view * model * vec4(position, 1.0f);
-    vs_out.FragPos = vec3(model * vec4(position, 1.0));
-    vs_out.Normal = transpose(inverse(mat3(model))) * normal;
-    vs_out.TexCoords = texCoords;
-    vs_out.FragPosLightSpace = lightSpaceMatrix * vec4(vs_out.FragPos, 1.0);
-}

src/5.advanced_lighting/3.1.3.shadow_mapping/shadow_mapping_depth.fs

@@ -1,6 +0,0 @@
-#version 330 core
-
-void main()
-{             
-    // gl_FragDepth = gl_FragCoord.z;
-}

src/5.advanced_lighting/3.1.3.shadow_mapping/shadow_mapping_depth.vs

@@ -1,10 +0,0 @@
-#version 330 core
-layout (location = 0) in vec3 position;
-
-uniform mat4 lightSpaceMatrix;
-uniform mat4 model;
-
-void main()
-{
-    gl_Position = lightSpaceMatrix * model * vec4(position, 1.0f);
-}