diff --git a/src/6.pbr/1.1.lighting/lighting.cpp b/src/6.pbr/1.1.lighting/lighting.cpp
index 0a3c9c8..ef722bd 100644
--- a/src/6.pbr/1.1.lighting/lighting.cpp
+++ b/src/6.pbr/1.1.lighting/lighting.cpp
@@ -135,10 +135,10 @@ int main()
 
         // render rows*column number of spheres with varying metallic/roughness values scaled by rows and columns respectively
         glm::mat4 model;
-        for (unsigned int row = 0; row < nrRows; ++row) 
+        for (int row = 0; row < nrRows; ++row) 
         {
             shader.setFloat("metallic", (float)row / (float)nrRows);
-            for (unsigned int col = 0; col < nrColumns; ++col) 
+            for (int col = 0; col < nrColumns; ++col) 
             {
                 // we clamp the roughness to 0.025 - 1.0 as perfectly smooth surfaces (roughness of 0.0) tend to look a bit off
                 // on direct lighting.
@@ -146,8 +146,8 @@ int main()
                 
                 model = glm::mat4();
                 model = glm::translate(model, glm::vec3(
-                    (col - (nrColumns / 2.)) * spacing, 
-                    (row - (nrRows / 2.)) * spacing, 
+                    (col - (nrColumns / 2)) * spacing, 
+                    (row - (nrRows / 2)) * spacing, 
                     0.0f
                 ));
                 shader.setMat4("model", model);
diff --git a/src/6.pbr/1.2.lighting_textured/lighting_textured.cpp b/src/6.pbr/1.2.lighting_textured/lighting_textured.cpp
index dafafb8..05ddccf 100644
--- a/src/6.pbr/1.2.lighting_textured/lighting_textured.cpp
+++ b/src/6.pbr/1.2.lighting_textured/lighting_textured.cpp
@@ -151,9 +151,9 @@ int main()
 
         // render rows*column number of spheres with material properties defined by textures (they all have the same material properties)
         glm::mat4 model;
-        for (unsigned int row = 0; row < nrRows; ++row)
+        for (int row = 0; row < nrRows; ++row)
         {
-            for (unsigned int col = 0; col < nrColumns; ++col)
+            for (int col = 0; col < nrColumns; ++col)
             {
                 model = glm::mat4();
                 model = glm::translate(model, glm::vec3(