Reviewed shaders and added comments

examples/resources/shaders/glsl330/base.vs

@@ -0,0 +1,26 @@
+#version 330
+
+// Input vertex attributes
+in vec3 vertexPosition;
+in vec2 vertexTexCoord;
+in vec3 vertexNormal;
+in vec4 vertexColor;
+
+// Input uniform values
+uniform mat4 mvpMatrix;
+
+// Output vertex attributes (to fragment shader)
+out vec2 fragTexCoord;
+out vec4 fragColor;
+
+// NOTE: Add here your custom variables 
+
+void main()
+{
+    // Send vertex attributes to fragment shader
+    fragTexCoord = vertexTexCoord;
+    fragColor = vertexColor;
+    
+    // Calculate final vertex position
+    gl_Position = mvpMatrix*vec4(vertexPosition, 1.0);
+}