Updated Use rlgl as standalone library (markdown)

Use-rlgl-as-standalone-library.md

@@ -1,21 +1,38 @@
 rlgl is a raylib module that let the user program in an OpenGL immediate mode style on any platform (internally uses OpenGL 1.1, 3.3 or ES 2.0). It can be used as standalone library.
 
+rlgl dependencies
+
 // TODO: Explain it a bit more
 
 ```c
-#include <GLFW/glfw3.h>     // Manage window creation and context
+/*******************************************************************************************
+*
+*   rlgl standalone sample
+*
+*   NOTE: Sample dependencies:
+*       GLFW3 - Window/Context creation and input management 
+*       GLEW - OpenGL 3.3 extensions loading
+*       raymath - Required by rlgl for vectorial/matrix maths
+*
+*   rlgl module is distributed with raylib 1.3 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2015 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
 
-#define RLGL_STANDALONE
+#include <GLFW/glfw3.h>     // Required for windows/context management
+
+#define RLGL_STANDALONE     // Use rlgl as standalone library (not raylib.h dependant)
 #include "../src/rlgl.h"
 
-#include <stdlib.h>
-#include <stdio.h>
-
+// Vector2 data type
 typedef struct {
     float x;
     float y;
 } Vector2;
 
+
 static void KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods)
 {
     if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
@@ -24,20 +41,20 @@ static void KeyCallback(GLFWwindow* window, int key, int scancode, int action, i
     }
 }
 
-static void DrawRectangleV(Vector2 position, Vector2 size, Color color);
+void DrawRectangleV(Vector2 position, Vector2 size, Color color);
 
 int main(void)
 {
+    // Initialization
+    //--------------------------------------------------------------------------------------
     const int screenWidth = 800;
     const int screenHeight = 450;
     
     GLFWwindow *window;
     
-    glfwSetErrorCallback(ErrorCallback);
-    
-    if (!glfwInit()) exit(EXIT_FAILURE);
+    if (!glfwInit()) exit(EXIT_FAILURE);    // Initialize GLFW3
    
-    window = glfwCreateWindow(screenWidth, screenHeight, "Testing rlgl standalone", NULL, NULL);
+    window = glfwCreateWindow(screenWidth, screenHeight, "rlgl standalone", NULL, NULL);
     
     if (!window)
     {
@@ -49,35 +66,48 @@ int main(void)
     glfwSwapInterval(1);
     glfwSetKeyCallback(window, KeyCallback);
     
-    rlglInit();
+    rlglInit();     // Initialize rlgl system (buffers)
     rlglInitGraphics(0, 0, screenWidth, screenHeight);
     rlClearColor(245, 245, 245, 255); // Define clear color
     
-    Vector2 size = { 400, 200 };
-    Vector2 position = { screenWidth/2 - size.x, screenHeight/2 - size.y};
-    Color color = { 255, 0, 0, 255 };        // RED
+    // Box variables
+    Vector2 boxSize = { 400, 200 };
+    Vector2 boxPosition = { 100, 100 };
+    Color boxColor = { 255, 0, 0, 255 };
+    //--------------------------------------------------------------------------------------
     
     while (!glfwWindowShouldClose(window))
     {
-        rlClearScreenBuffers();
+        // Update
+        //----------------------------------------------------------------------------------
+        glfwPollEvents();       // Capture input events
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        rlClearScreenBuffers();                 // Clear backbuffer
         
-        DrawRectangleV(position, size, color);
+        DrawRectangleV(position, size, color);  // Load vertex buffers
         
-        rlglDraw();
+        rlglDraw();                             // Draw everything
         
-        glfwSwapBuffers(window);
-        glfwPollEvents();
+        glfwSwapBuffers(window);                // Copy backbuffer to frontbuffer
+        //----------------------------------------------------------------------------------
     }
     
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
     rlglClose();
     
     glfwDestroyWindow(window);
     glfwTerminate();
+    //--------------------------------------------------------------------------------------
     
     return 0;
 }
 
-static void DrawRectangleV(Vector2 position, Vector2 size, Color color)
+// Draw a rectangle (OpenGL immediate mode style)
+void DrawRectangleV(Vector2 position, Vector2 size, Color color)
 {
     rlBegin(RL_TRIANGLES);
         rlColor4ub(color.r, color.g, color.b, color.a);