raylib-src/examples/textures/textures_srcrec_dstrec.c

/*******************************************************************************************
*
*   raylib [textures] example - Texture source and destination rectangles
*
*   This example has been created using 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)
*
********************************************************************************************/

#include "raylib.h"

int main()
{
    // Initialization
    //--------------------------------------------------------------------------------------
    int screenWidth = 800;
    int screenHeight = 450;

    InitWindow(screenWidth, screenHeight, "raylib [textures] examples - texture source and destination rectangles");

    // NOTE: Textures MUST be loaded after Window initialization (OpenGL context is required)
    Texture2D guybrush = LoadTexture("resources/guybrush.png");        // Texture loading

    int frameWidth = guybrush.width/7;
    int frameHeight = guybrush.height;
    
    // NOTE: Source rectangle (part of the texture to use for drawing)
    Rectangle sourceRec = { 0, 0, frameWidth, frameHeight };

    // NOTE: Destination rectangle (screen rectangle where drawing part of texture)
    Rectangle destRec = { screenWidth/2, screenHeight/2, frameWidth*2, frameHeight*2 };

    // NOTE: Origin of the texture (rotation/scale point), it's relative to destination rectangle size
    Vector2 origin = { frameWidth, frameHeight };
    
    int rotation = 0;
    
    SetTargetFPS(60);
    //--------------------------------------------------------------------------------------

    // Main game loop
    while (!WindowShouldClose())    // Detect window close button or ESC key
    {
        // Update
        //----------------------------------------------------------------------------------
        rotation++;
        //----------------------------------------------------------------------------------

        // Draw
        //----------------------------------------------------------------------------------
        BeginDrawing();

            ClearBackground(RAYWHITE);

            // NOTE: Using DrawTexturePro() we can easily rotate and scale the part of the texture we draw
            // sourceRec defines the part of the texture we use for drawing
            // destRec defines the rectangle where our texture part will fit (scaling it to fit)
            // origin defines the point of the texture used as reference for rotation and scaling
            // rotation defines the texture rotation (using origin as rotation point)
            DrawTexturePro(guybrush, sourceRec, destRec, origin, rotation, WHITE);

            DrawLine(destRec.x, 0, destRec.x, screenHeight, GRAY);
            DrawLine(0, destRec.y, screenWidth, destRec.y, GRAY);

        EndDrawing();
        //----------------------------------------------------------------------------------
    }

    // De-Initialization
    //--------------------------------------------------------------------------------------
    UnloadTexture(guybrush);       // Texture unloading

    CloseWindow();                // Close window and OpenGL context
    //--------------------------------------------------------------------------------------

    return 0;
}