Reviewed shaders and added comments

examples/resources/shaders/phong.vs

@@ -1,29 +0,0 @@
-#version 330
-
-// Vertex input data
-in vec3 vertexPosition;
-in vec2 vertexTexCoord;
-in vec3 vertexNormal;
-
-// Projection and model data
-uniform mat4 mvpMatrix;
-
-uniform mat4 modelMatrix;
-//uniform mat4 viewMatrix;  // Not used
-
-// Attributes to fragment shader
-out vec2 fragTexCoord;
-out vec3 fragNormal;
-
-void main()
-{
-    // Send texture coord to fragment shader
-    fragTexCoord = vertexTexCoord;
-    
-    // Calculate view vector normal from model
-    mat3 normalMatrix = transpose(inverse(mat3(modelMatrix)));
-    fragNormal = normalize(normalMatrix*vertexNormal);
-    
-    // Calculate final vertex position
-    gl_Position = mvpMatrix*vec4(vertexPosition, 1.0);
-}