2.3.csm: fix mac os issues

1. Lower OpenGL demands: the demo works fine with v4.1. No need to require v4.6 which is not available on mac os.

2. Use actual framebuffer size to fix viewport issues on retina displays.

src/8.guest/2021/2.csm/10.debug_cascade.fs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 out vec4 FragColor;
 
 uniform vec4 color;

src/8.guest/2021/2.csm/10.debug_cascade.vs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 layout (location = 0) in vec3 aPos;
 
 uniform mat4 view;

src/8.guest/2021/2.csm/10.debug_quad.vs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 layout (location = 0) in vec3 aPos;
 layout (location = 1) in vec2 aTexCoords;
 

src/8.guest/2021/2.csm/10.debug_quad_depth.fs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 out vec4 FragColor;
 
 in vec2 TexCoords;

src/8.guest/2021/2.csm/10.shadow_mapping.fs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 out vec4 FragColor;
 
 in VS_OUT {
@@ -16,7 +16,7 @@ uniform float farPlane;
 
 uniform mat4 view;
 
-layout (std140, binding = 0) uniform LightSpaceMatrices
+layout (std140) uniform LightSpaceMatrices
 {
     mat4 lightSpaceMatrices[16];
 };

src/8.guest/2021/2.csm/10.shadow_mapping.vs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 layout (location = 0) in vec3 aPos;
 layout (location = 1) in vec3 aNormal;
 layout (location = 2) in vec2 aTexCoords;

src/8.guest/2021/2.csm/10.shadow_mapping_depth.fs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 
 void main()
 {             

src/8.guest/2021/2.csm/10.shadow_mapping_depth.gs

@@ -1,12 +1,15 @@
-#version 460 core
+#version 410 core
 
 layout(triangles, invocations = 5) in;
 layout(triangle_strip, max_vertices = 3) out;
 
-layout (std140, binding = 0) uniform LightSpaceMatrices
+layout (std140/*, binding = 0*/) uniform LightSpaceMatrices
 {
     mat4 lightSpaceMatrices[16];
 };
+/*
+uniform mat4 lightSpaceMatrices[16];
+*/
 
 void main()
 {          

src/8.guest/2021/2.csm/10.shadow_mapping_depth.vs

@@ -1,4 +1,4 @@
-#version 460 core
+#version 410 core
 layout (location = 0) in vec3 aPos;
 
 uniform mat4 model;

src/8.guest/2021/2.csm/shadow_mapping.cpp

@@ -30,6 +30,10 @@ void drawCascadeVolumeVisualizers(const std::vector<glm::mat4>& lightMatrices, S
 const unsigned int SCR_WIDTH = 2560;
 const unsigned int SCR_HEIGHT = 1440;
 
+// framebuffer size
+int fb_width;
+int fb_height;
+
 // camera
 Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
 float lastX = (float)SCR_WIDTH / 2.0;
@@ -68,8 +72,8 @@ int main()
     // glfw: initialize and configure
     // ------------------------------
     glfwInit();
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
-    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 6);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
     glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
 
 #ifdef __APPLE__
@@ -89,6 +93,7 @@ int main()
     glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
     glfwSetCursorPosCallback(window, mouse_callback);
     glfwSetScrollCallback(window, scroll_callback);
+    glfwGetFramebufferSize(window, &fb_width, &fb_height);
 
     // tell GLFW to capture our mouse
     glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
@@ -239,15 +244,15 @@ int main()
         glBindFramebuffer(GL_FRAMEBUFFER, 0);
 
         // reset viewport
-        glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+        glViewport(0, 0, fb_width, fb_height);
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
         // 2. render scene as normal using the generated depth/shadow map  
         // --------------------------------------------------------------
-        glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
+        glViewport(0, 0, fb_width, fb_height);
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
         shader.use();
-        const glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, cameraNearPlane, cameraFarPlane);
+        const glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)fb_width / (float)fb_height, cameraNearPlane, cameraFarPlane);
         const glm::mat4 view = camera.GetViewMatrix();
         shader.setMat4("projection", projection);
         shader.setMat4("view", view);
@@ -540,7 +545,7 @@ void processInput(GLFWwindow *window)
     fPress = glfwGetKey(window, GLFW_KEY_F);
 
     static int plusPress = GLFW_RELEASE;
-    if (glfwGetKey(window, GLFW_KEY_KP_ADD) == GLFW_RELEASE && plusPress == GLFW_PRESS)
+    if (glfwGetKey(window, GLFW_KEY_N) == GLFW_RELEASE && plusPress == GLFW_PRESS)
     {
         debugLayer++;
         if (debugLayer > shadowCascadeLevels.size())
@@ -548,7 +553,7 @@ void processInput(GLFWwindow *window)
             debugLayer = 0;
         }
     }
-    plusPress = glfwGetKey(window, GLFW_KEY_KP_ADD);
+    plusPress = glfwGetKey(window, GLFW_KEY_N);
 
     static int cPress = GLFW_RELEASE;
     if (glfwGetKey(window, GLFW_KEY_C) == GLFW_RELEASE && cPress == GLFW_PRESS)
@@ -564,6 +569,8 @@ void framebuffer_size_callback(GLFWwindow* window, int width, int height)
 {
     // make sure the viewport matches the new window dimensions; note that width and 
     // height will be significantly larger than specified on retina displays.
+    fb_width = width;
+    fb_height = height;
     glViewport(0, 0, width, height);
 }
 
@@ -662,7 +669,7 @@ std::vector<glm::vec4> getFrustumCornersWorldSpace(const glm::mat4& proj, const
 glm::mat4 getLightSpaceMatrix(const float nearPlane, const float farPlane)
 {
     const auto proj = glm::perspective(
-        glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, nearPlane,
+        glm::radians(camera.Zoom), (float)fb_width / (float)fb_height, nearPlane,
         farPlane);
     const auto corners = getFrustumCornersWorldSpace(proj, camera.GetViewMatrix());
 
@@ -712,7 +719,6 @@ glm::mat4 getLightSpaceMatrix(const float nearPlane, const float farPlane)
     }
 
     const glm::mat4 lightProjection = glm::ortho(minX, maxX, minY, maxY, minZ, maxZ);
-
     return lightProjection * lightView;
 }