feat: backporting existing raylib-cs examples and new official raylib examples to WASM, adopting raylib's original code style

Examples/Textures/ImageChannel.cs

@@ -0,0 +1,149 @@
+/*******************************************************************************************
+*
+*   raylib [textures] example - image channel
+*
+*   NOTE: Images are loaded in CPU memory (RAM); textures are loaded in GPU memory (VRAM)
+*
+*   Example complexity rating: [★★☆☆] 2/4
+*
+*   Example originally created with raylib 5.5, last time updated with raylib 5.5
+*
+*   Example contributed by Bruno Cabral (@brccabral) and reviewed by Ramon Santamaria (@raysan5)
+*
+*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
+*   BSD-like license that allows static linking with closed source software
+*
+*   Copyright (c) 2024-2025 Bruno Cabral (@brccabral) and Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+using System.Numerics;
+using static Raylib_cs.Raylib;
+
+namespace Examples.Textures;
+
+public partial class ImageChannel : IExample
+{
+    private const int screenWidth = 800;
+    private const int screenHeight = 450;
+
+    public string Name => "Textures / Image Channel";
+
+    public string Title => "raylib [textures] example - image channel";
+
+    private Texture2D fudesumiTexture;
+    private Texture2D textureAlpha;
+    private Texture2D textureRed;
+    private Texture2D textureGreen;
+    private Texture2D textureBlue;
+    private Texture2D backgroundTexture;
+
+    private Rectangle fudesumiRec;
+    private Rectangle fudesumiPos;
+    private Rectangle redPos;
+    private Rectangle greenPos;
+    private Rectangle bluePos;
+    private Rectangle alphaPos;
+
+    public void Init()
+    {
+        var fudesumiImage = LoadImage("resources/fudesumi.png");
+
+        var imageAlpha = ImageFromChannel(fudesumiImage, 3);
+        ImageAlphaMask(ref imageAlpha, imageAlpha);
+
+        var imageRed = ImageFromChannel(fudesumiImage, 0);
+        ImageAlphaMask(ref imageRed, imageAlpha);
+
+        var imageGreen = ImageFromChannel(fudesumiImage, 1);
+        ImageAlphaMask(ref imageGreen, imageAlpha);
+
+        var imageBlue = ImageFromChannel(fudesumiImage, 2);
+        ImageAlphaMask(ref imageBlue, imageAlpha);
+
+        var backgroundImage = GenImageChecked(screenWidth, screenHeight, screenWidth / 20, screenHeight / 20, Color.Orange, Color.Yellow);
+
+        fudesumiTexture = LoadTextureFromImage(fudesumiImage);
+        textureAlpha = LoadTextureFromImage(imageAlpha);
+        textureRed = LoadTextureFromImage(imageRed);
+        textureGreen = LoadTextureFromImage(imageGreen);
+        textureBlue = LoadTextureFromImage(imageBlue);
+        backgroundTexture = LoadTextureFromImage(backgroundImage);
+
+        fudesumiRec = new Rectangle(0, 0, fudesumiImage.Width, fudesumiImage.Height);
+
+        fudesumiPos = new Rectangle(50, 10, fudesumiImage.Width * 0.8f, fudesumiImage.Height * 0.8f);
+        redPos = new Rectangle(410, 10, fudesumiPos.Width / 2.0f, fudesumiPos.Height / 2.0f);
+        greenPos = new Rectangle(600, 10, fudesumiPos.Width / 2.0f, fudesumiPos.Height / 2.0f);
+        bluePos = new Rectangle(410, 230, fudesumiPos.Width / 2.0f, fudesumiPos.Height / 2.0f);
+        alphaPos = new Rectangle(600, 230, fudesumiPos.Width / 2.0f, fudesumiPos.Height / 2.0f);
+
+        UnloadImage(fudesumiImage);
+        UnloadImage(imageAlpha);
+        UnloadImage(imageRed);
+        UnloadImage(imageGreen);
+        UnloadImage(imageBlue);
+        UnloadImage(backgroundImage);
+    }
+
+    public void Update()
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        // Nothing to update...
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+        DrawTexture(backgroundTexture, 0, 0, Color.White);
+        DrawTexturePro(fudesumiTexture, fudesumiRec, fudesumiPos, new Vector2(0, 0), 0, Color.White);
+
+        DrawTexturePro(textureRed, fudesumiRec, redPos, new Vector2(0, 0), 0, Color.Red);
+        DrawTexturePro(textureGreen, fudesumiRec, greenPos, new Vector2(0, 0), 0, Color.Green);
+        DrawTexturePro(textureBlue, fudesumiRec, bluePos, new Vector2(0, 0), 0, Color.Blue);
+        DrawTexturePro(textureAlpha, fudesumiRec, alphaPos, new Vector2(0, 0), 0, Color.White);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    public void Unload()
+    {
+        UnloadTexture(backgroundTexture);
+        UnloadTexture(fudesumiTexture);
+        UnloadTexture(textureRed);
+        UnloadTexture(textureGreen);
+        UnloadTexture(textureBlue);
+        UnloadTexture(textureAlpha);
+    }
+
+    public static int Main()
+    {
+        // Initialization
+        //--------------------------------------------------------------------------------------
+        InitWindow(screenWidth, screenHeight, "raylib [textures] example - image channel");
+
+        SetTargetFPS(60);
+        //--------------------------------------------------------------------------------------
+
+        var game = new ImageChannel();
+        game.Init();
+
+        // Main game loop
+        while (!WindowShouldClose())    // Detect window close button or ESC key
+        {
+            game.Update();
+        }
+
+        game.Unload();
+
+        // De-Initialization
+        //--------------------------------------------------------------------------------------
+        CloseWindow();                // Close window and OpenGL context
+        //--------------------------------------------------------------------------------------
+
+        return 0;
+    }
+}