Update/merge examples back into main repo (#192)

Examples/Shaders/HotReloading.cs

@@ -0,0 +1,138 @@
+/*******************************************************************************************
+*
+*   raylib [shaders] example - Hot reloading
+*
+*   NOTE: This example requires raylib OpenGL 3.3 for shaders support and only #version 330
+*         is currently supported. OpenGL ES 2.0 platforms are not supported at the moment.
+*
+*   This example has been created using raylib 3.0 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2020 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+using System.Numerics;
+using static Raylib_cs.Raylib;
+
+namespace Examples.Shaders;
+
+public class HotReloading
+{
+    public static int Main()
+    {
+        // Initialization
+        //--------------------------------------------------------------------------------------
+        int screenWidth = 800;
+        int screenHeight = 450;
+
+        InitWindow(screenWidth, screenHeight, "raylib [shaders] example - hot reloading");
+
+        string fragShaderFileName = "resources/shaders/glsl330/reload.fs";
+        long fragShaderFileModTime = GetFileModTime(fragShaderFileName);
+
+        // Load raymarching shader
+        // NOTE: Defining 0 (NULL) for vertex shader forces usage of internal default vertex shader
+        Shader shader = LoadShader(null, fragShaderFileName);
+
+        // Get shader locations for required uniforms
+        int resolutionLoc = GetShaderLocation(shader, "resolution");
+        int mouseLoc = GetShaderLocation(shader, "mouse");
+        int timeLoc = GetShaderLocation(shader, "time");
+
+        float[] resolution = new[] { (float)screenWidth, (float)screenHeight };
+        Raylib.SetShaderValue(shader, resolutionLoc, resolution, ShaderUniformDataType.SHADER_UNIFORM_VEC2);
+
+        float totalTime = 0.0f;
+        bool shaderAutoReloading = false;
+
+        SetTargetFPS(60);
+        //--------------------------------------------------------------------------------------
+
+        // Main game loop
+        while (!WindowShouldClose())
+        {
+            // Update
+            //----------------------------------------------------------------------------------
+            totalTime += GetFrameTime();
+            Vector2 mouse = GetMousePosition();
+            float[] mousePos = new[] { mouse.X, mouse.Y };
+
+            // Set shader required uniform values
+            Raylib.SetShaderValue(shader, timeLoc, totalTime, ShaderUniformDataType.SHADER_UNIFORM_FLOAT);
+            Raylib.SetShaderValue(shader, mouseLoc, mousePos, ShaderUniformDataType.SHADER_UNIFORM_VEC2);
+
+            // Hot shader reloading
+            if (shaderAutoReloading || (IsMouseButtonPressed(MouseButton.MOUSE_LEFT_BUTTON)))
+            {
+                long currentFragShaderModTime = GetFileModTime(fragShaderFileName);
+
+                // Check if shader file has been modified
+                if (currentFragShaderModTime != fragShaderFileModTime)
+                {
+                    // Try reloading updated shader
+                    Shader updatedShader = LoadShader(null, fragShaderFileName);
+
+                    // It was correctly loaded
+                    if (updatedShader.Id != 0) //rlGetShaderIdDefault())
+                    {
+                        UnloadShader(shader);
+                        shader = updatedShader;
+
+                        // Get shader locations for required uniforms
+                        resolutionLoc = GetShaderLocation(shader, "resolution");
+                        mouseLoc = GetShaderLocation(shader, "mouse");
+                        timeLoc = GetShaderLocation(shader, "time");
+
+                        // Reset required uniforms
+                        Raylib.SetShaderValue(
+                            shader,
+                            resolutionLoc,
+                            resolution,
+                            ShaderUniformDataType.SHADER_UNIFORM_VEC2
+                        );
+                    }
+
+                    fragShaderFileModTime = currentFragShaderModTime;
+                }
+            }
+
+            if (IsKeyPressed(KeyboardKey.KEY_A))
+            {
+                shaderAutoReloading = !shaderAutoReloading;
+            }
+            //----------------------------------------------------------------------------------
+
+            // Draw
+            //----------------------------------------------------------------------------------
+            BeginDrawing();
+            ClearBackground(Color.RAYWHITE);
+
+            // We only draw a white full-screen rectangle, frame is generated in shader
+            BeginShaderMode(shader);
+            DrawRectangle(0, 0, screenWidth, screenHeight, Color.WHITE);
+            EndShaderMode();
+
+            string info = $"PRESS [A] to TOGGLE SHADER AUTOLOADING: {(shaderAutoReloading ? "AUTO" : "MANUAL")}";
+            DrawText(info, 10, 10, 10, shaderAutoReloading ? Color.RED : Color.BLACK);
+            if (!shaderAutoReloading)
+            {
+                DrawText("MOUSE CLICK to SHADER RE-LOADING", 10, 30, 10, Color.BLACK);
+            }
+
+            // DrawText($"Shader last modification: ", 10, 430, 10, Color.BLACK);
+
+            EndDrawing();
+            //----------------------------------------------------------------------------------
+        }
+
+        // De-Initialization
+        //--------------------------------------------------------------------------------------
+        UnloadShader(shader);
+
+        CloseWindow();
+        //--------------------------------------------------------------------------------------
+
+        return 0;
+    }
+}