raylib-cs/Examples/shaders/shaders_custom_uniform.cs

using Raylib;
using static Raylib.Raylib;
using static Raylib.CameraType;
using static Raylib.CameraMode;
using static Raylib.TexmapIndex;

public partial class shaders_custom_uniform
{
    /*******************************************************************************************
    *
    *   raylib [shaders] example - Apply a postprocessing shader and connect a custom uniform variable
    *
    *   NOTE: This example requires raylib OpenGL 3.3 or ES2 versions for shaders support,
    *         OpenGL 1.1 does not support shaders, recompile raylib to OpenGL 3.3 version.
    *
    *   NOTE: Shaders used in this example are #version 330 (OpenGL 3.3), to test this example
    *         on OpenGL ES 2.0 platforms (Android, Raspberry Pi, HTML5), use #version 100 shaders
    *         raylib comes with shaders ready for both versions, check raylib/shaders install folder
    *
    *   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)
    *
    ********************************************************************************************/
    
    
    public static int Main()
    {
        // Initialization
        //--------------------------------------------------------------------------------------
        int screenWidth = 800;
        int screenHeight = 450;
        
        SetConfigFlags(FLAG_MSAA_4X_HINT);      // Enable Multi Sampling Anti Aliasing 4x (if available)
    
        InitWindow(screenWidth, screenHeight, "raylib [shaders] example - custom uniform variable");
    
        // Define the camera to look into our 3d world
        Camera3D camera = new Camera3D();
        camera.position = new Vector3( 8.0f, 8.0f, 8.0f );
        camera.target = new Vector3( 0.0f, 1.5f, 0.0f );
        camera.up = new Vector3( 0.0f, 1.0f, 0.0f );
        camera.fovy = 45.0f;
        camera.type = CAMERA_PERSPECTIVE;
    
        Model model = LoadModel("resources/models/barracks.obj");                   // Load OBJ model
        Texture2D texture = LoadTexture("resources/models/barracks_diffuse.png");   // Load model texture (diffuse map)
        model.material.maps[(int)MAP_ALBEDO].texture = texture;                         // Set model diffuse texture
    
        Vector3 position = new Vector3( 0.0f, 0.0f, 0.0f );                                // Set model position
        
        Shader shader = LoadShader("resources/shaders/glsl330/base.vs", 
                                   "resources/shaders/glsl330/swirl.fs");       // Load postpro shader
        
        // Get variable (uniform) location on the shader to connect with the program
        // NOTE: If uniform variable could not be found in the shader, function returns -1
        int swirlCenterLoc = GetShaderLocation(shader, "center");
        
        float[] swirlCenter = new float[2] { (float)screenWidth/2, (float)screenHeight/2 };
        
        // Create a RenderTexture2D to be used for render to texture
        RenderTexture2D target = LoadRenderTexture(screenWidth, screenHeight);
        
        // Setup orbital camera
        SetCameraMode(camera, (int)CAMERA_ORBITAL);  // Set an orbital camera mode
    
        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
            //----------------------------------------------------------------------------------
            Vector2 mousePosition = GetMousePosition();
    
            swirlCenter[0] = mousePosition.x;
            swirlCenter[1] = screenHeight - mousePosition.y;
    
            // Send new value to the shader to be used on drawing
            SetShaderValue(shader, swirlCenterLoc, swirlCenter, 2);
            
            UpdateCamera(ref camera);              // Update camera
            //----------------------------------------------------------------------------------
    
            // Draw
            //----------------------------------------------------------------------------------
            BeginDrawing();
    
                ClearBackground(RAYWHITE);
                
                BeginTextureMode(target);   // Enable drawing to texture
    
                    BeginMode3D(camera);
    
                        DrawModel(model, position, 0.5f, WHITE);   // Draw 3d model with texture
    
                        DrawGrid(10, 1.0f);     // Draw a grid
    
                    EndMode3D();
                    
                    DrawText("TEXT DRAWN IN RENDER TEXTURE", 200, 10, 30, RED);
                
                EndTextureMode();           // End drawing to texture (now we have a texture available for next passes)
                
                BeginShaderMode(shader);
                
                    // NOTE: Render texture must be y-flipped due to default OpenGL coordinates (left-bottom)
                    DrawTextureRec(target.texture, new Rectangle( 0, 0, target.texture.width, -target.texture.height ), new Vector2( 0, 0 ), WHITE);
                
                EndShaderMode();
                
                DrawText("(c) Barracks 3D model by Alberto Cano", screenWidth - 220, screenHeight - 20, 10, GRAY);
                
                DrawFPS(10, 10);
    
            EndDrawing();
            //----------------------------------------------------------------------------------
        }
    
        // De-Initialization
        //--------------------------------------------------------------------------------------
        UnloadShader(shader);           // Unload shader
        UnloadTexture(texture);         // Unload texture
        UnloadModel(model);             // Unload model
        UnloadRenderTexture(target);    // Unload render texture
    
        CloseWindow();                  // Close window and OpenGL context
        //--------------------------------------------------------------------------------------
    
        return 0;
    }    
}