Update/merge examples back into main repo (#192)

Examples/resources/shaders/glsl330/overdraw.fs

@@ -0,0 +1,26 @@
+#version 330
+
+// Input vertex attributes (from vertex shader)
+in vec2 fragTexCoord;
+in vec4 fragColor;
+
+// Input uniform values
+uniform sampler2D texture0;
+uniform vec4 colDiffuse;
+
+// Output fragment color
+out vec4 finalColor;
+
+// NOTE: Add here your custom variables
+
+void main()
+{
+    // To show overdraw, we just render all the fragments
+    // with a solid color and some transparency
+
+    // NOTE: This is not a postpro render,
+    // it will only render all screen texture in a plain color
+
+    finalColor = vec4(1.0, 0.0, 0.0, 0.2);
+}
+