new example: core_window_scale_letterbox

examples/core/core_window_scale_letterbox.c

@@ -0,0 +1,88 @@
+/*******************************************************************************************
+*
+*   raylib [core] example - window scale letterbox
+*
+*   This example has been created using raylib 2.5 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2019 Anata and Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#define max(a, b) ((a)>(b)? (a) : (b))
+#define min(a, b) ((a)<(b)? (a) : (b))
+
+int main()
+{
+    const int windowWidth = 800;
+    const int windowHeight = 450;
+
+    // Enable config flags for resizable window and vertical synchro
+    SetConfigFlags(FLAG_WINDOW_RESIZABLE | FLAG_VSYNC_HINT);
+    InitWindow(windowWidth, windowHeight, "raylib [core] example - window scale letterbox");
+    SetWindowMinSize(320, 240);
+
+    int gameScreenWidth = 640;
+    int gameScreenHeight = 480;
+    
+    // Render texture initialization
+    RenderTexture2D target = LoadRenderTexture(gameScreenWidth, gameScreenHeight);
+    SetTextureFilter(target.texture, FILTER_BILINEAR);  // Texture scale filter to use
+    
+    Color colors[10] = { 0 };
+    for (int i = 0; i < 10; i++) colors[i] = (Color){ GetRandomValue(100, 250), GetRandomValue(50, 150), GetRandomValue(10, 100), 255 };
+    
+    SetTargetFPS(60);
+    //--------------------------------------------------------------------------------------
+    
+    // Main game loop
+    while( !WindowShouldClose() )       // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        // Compute required framebuffer scaling
+        float scale = min((float)GetScreenWidth()/gameScreenWidth, (float)GetScreenHeight()/gameScreenHeight);
+        
+        if (IsKeyPressed(KEY_SPACE)) 
+        {
+            // Recalculate random colors for the bars
+            for (int i = 0; i < 10; i++) colors[i] = (Color){ GetRandomValue(100, 250), GetRandomValue(50, 150), GetRandomValue(10, 100), 255 };
+        }
+        //----------------------------------------------------------------------------------
+        
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+            ClearBackground(BLACK);
+            
+            // Draw everything in the render texture
+            BeginTextureMode(target);
+            
+                ClearBackground(RAYWHITE);         // Clear render texture background color
+                
+                for (int i = 0; i < 10; i++) DrawRectangle(0, (gameScreenHeight/10)*i, gameScreenWidth, gameScreenHeight/10, colors[i]);
+                
+                DrawText("You can resize the window,\nand see the screen scaling!", 10, 25, 20, WHITE);
+            
+            EndTextureMode();
+
+            // Draw RenderTexture2D to window, properly scaled
+            DrawTexturePro(target.texture, (Rectangle){ 0.0f, 0.0f, (float)target.texture.width, (float)-target.texture.height },
+                           (Rectangle){ (GetScreenWidth() - ((float)gameScreenWidth*scale))*0.5, (GetScreenHeight() - ((float)gameScreenHeight*scale))*0.5, 
+                           (float)gameScreenWidth*scale, (float)gameScreenHeight*scale }, (Vector2){ 0, 0 }, 0.0f, WHITE);
+                           
+        EndDrawing();
+        //--------------------------------------------------------------------------------------
+    }
+    
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    UnloadRenderTexture(target);    // Unload render texture
+    
+    CloseWindow();                  // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+    
+    return 0;
+}