Add ascii post processing (#5213)

examples/shaders/shaders_ascii_effect.c

@@ -0,0 +1,119 @@
+/*******************************************************************************************
+*
+*   raylib [shaders] example - ascii effect
+*
+*   Example complexity rating: [★☆☆☆] 1/4
+*
+*   Example originally created with raylib 5.5, last time updated with raylib 5.6
+*
+*   Example contributed by Maicon Santana (@maiconpintoabreu) 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) 2025-2025 Maicon Santana (@maiconpintoabreu)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#if defined(PLATFORM_DESKTOP)
+    #define GLSL_VERSION            330
+#else   // PLATFORM_ANDROID, PLATFORM_WEB
+    #define GLSL_VERSION            100
+#endif
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [shaders] example - ascii effect");
+
+    // Texture to test static drawing
+    Texture2D fudesumi = LoadTexture("resources/fudesumi.png");
+    // Texture to test moving drawing
+    Texture2D raysan = LoadTexture("resources/raysan.png");
+
+    // Load shader to be used on postprocessing
+    Shader shader = LoadShader(0, TextFormat("resources/shaders/glsl%i/ascii.fs", GLSL_VERSION));
+
+    // These locations are used to send data to the GPU.
+    int resolutionLoc = GetShaderLocation(shader, "resolution");
+    int fontSizeLoc = GetShaderLocation(shader, "fontSize");
+
+    // Set the character size for the ASCII effect
+    float fontSize = 4.0f;
+
+    // Send the updated values to the shader
+    float resolution[2] = { (float)screenWidth, (float)screenHeight };
+    SetShaderValue(shader, resolutionLoc, resolution, SHADER_UNIFORM_VEC2);
+    SetShaderValue(shader, fontSizeLoc, &fontSize, SHADER_UNIFORM_FLOAT);
+
+    Vector2 circlePos = (Vector2){40.0f, (float)screenHeight * 0.5f};
+    float circleSpeed = 1.0f;
+
+    // RenderTexture to apply the postprocessing later
+    RenderTexture2D target = LoadRenderTexture(screenWidth, screenHeight);
+
+    SetTargetFPS(60);                   // Set our game to run at 60 frames-per-second
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        if (circlePos.x > 200.0f || circlePos.x < 40.0f) {
+            circleSpeed *= -1;
+        }
+        circlePos.x += circleSpeed;
+
+        // Draw
+        //----------------------------------------------------------------------------------
+
+        BeginTextureMode(target);
+            ClearBackground(WHITE); // The background of the scene itself
+            
+            DrawTexture(fudesumi, 500, -30, WHITE);    // Using custom shader
+            DrawTextureV(raysan, circlePos, WHITE);
+
+        EndTextureMode();
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+
+            BeginShaderMode(shader);
+
+                // Draw the scene texture (that we rendered earlier) to the screen.
+                // The shader will process every pixel of this texture.
+                DrawTextureRec(target.texture, 
+                               (Rectangle){ 0, 0, (float)target.texture.width, (float)-target.texture.height }, 
+                               (Vector2){ 0, 0 }, 
+                               WHITE);
+            EndShaderMode();
+
+            DrawRectangle(0, 0, screenWidth, 40, BLACK);
+            DrawText("Ascii effect", 120, 10, 20, LIGHTGRAY);
+            DrawFPS(10, 10);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    UnloadShader(shader);       // Unload shader
+    UnloadTexture(fudesumi);    // Unload texture
+    UnloadTexture(raysan);      // Unload texture
+
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}