|  | /******************************************************************************************* | 
						
						
							|  | * | 
						
						
							|  | *   raylib [shaders] example - mandelbrot set | 
						
						
							|  | * | 
						
						
							|  | *   Example complexity rating: [★★★☆] 3/4 | 
						
						
							|  | * | 
						
						
							|  | *   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) | 
						
						
							|  | * | 
						
						
							|  | *   Example originally created with raylib 5.6, last time updated with raylib 5.6 | 
						
						
							|  | * | 
						
						
							|  | *   Example contributed by Jordi Santonja (@JordSant) | 
						
						
							|  | *   Based on previous work by Josh Colclough (@joshcol9232) | 
						
						
							|  | * | 
						
						
							|  | *   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 Jordi Santonja (@JordSant) | 
						
						
							|  | * | 
						
						
							|  | ********************************************************************************************/ | 
						
						
							|  | 
 | 
						
						
							|  | #include "raylib.h" | 
						
						
							|  | #include <math.h> | 
						
						
							|  |  | 
						
						
							|  | #if defined(PLATFORM_DESKTOP) | 
						
						
							|  |     #define GLSL_VERSION            330 | 
						
						
							|  | #else   // PLATFORM_ANDROID, PLATFORM_WEB | 
						
						
							|  |     #define GLSL_VERSION            100 | 
						
						
							|  | #endif | 
						
						
							|  |  | 
						
						
							|  | // A few good interesting places | 
						
						
							|  | const float pointsOfInterest[6][3] = | 
						
						
							|  | { | 
						
						
							|  |     { -1.76826775f, -0.00422996283f, 28435.9238f }, | 
						
						
							|  |     { 0.322004497f, -0.0357099883f, 56499.7266f }, | 
						
						
							|  |     { -0.748880744f, -0.0562955774f, 9237.59082f }, | 
						
						
							|  |     { -1.78385007f, -0.0156200649f, 14599.5283f }, | 
						
						
							|  |     { -0.0985441282f, -0.924688697f, 26259.8535f }, | 
						
						
							|  |     { 0.317785531f, -0.0322612226f, 29297.9258f }, | 
						
						
							|  | }; | 
						
						
							|  | 
 | 
						
						
							|  | const int screenWidth = 800; | 
						
						
							|  | const int screenHeight = 450; | 
						
						
							|  | const float zoomSpeed = 1.01f; | 
						
						
							|  | const float offsetSpeedMul = 2.0f; | 
						
						
							|  | 
 | 
						
						
							|  | const float startingZoom = 0.6f; | 
						
						
							|  | const float startingOffset[2] = { -0.5f, 0.0f }; | 
						
						
							|  | 
 | 
						
						
							|  | //------------------------------------------------------------------------------------ | 
						
						
							|  | // Program main entry point | 
						
						
							|  | //------------------------------------------------------------------------------------ | 
						
						
							|  | int main(void) | 
						
						
							|  | { | 
						
						
							|  |     // Initialization | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |     InitWindow(screenWidth, screenHeight, "raylib [shaders] example - mandelbrot set"); | 
						
						
							|  | 
 | 
						
						
							|  |     // Load mandelbrot set shader | 
						
						
							|  |     // NOTE: Defining 0 (NULL) for vertex shader forces usage of internal default vertex shader | 
						
						
							|  |     Shader shader = LoadShader(0, TextFormat("resources/shaders/glsl%i/mandelbrot_set.fs", GLSL_VERSION)); | 
						
						
							|  | 
 | 
						
						
							|  |     // Create a RenderTexture2D to be used for render to texture | 
						
						
							|  |     RenderTexture2D target = LoadRenderTexture(GetScreenWidth(), GetScreenHeight()); | 
						
						
							|  | 
 | 
						
						
							|  |     // Offset and zoom to draw the mandelbrot set at. (centered on screen and default size) | 
						
						
							|  |     float offset[2] = { startingOffset[0], startingOffset[1] }; | 
						
						
							|  |     float zoom = startingZoom; | 
						
						
							|  |     // Depending on the zoom the mximum number of iterations must be adapted to get more detail as we zzoom in | 
						
						
							|  | 	// The solution is not perfect, so a control has been added to increase/decrease the number of iterations with UP/DOWN keys | 
						
						
							|  |     int maxIterations = 333; | 
						
						
							|  |     float maxIterationsMultiplier = 166.5f; | 
						
						
							|  | 
 | 
						
						
							|  |     // Get variable (uniform) locations on the shader to connect with the program | 
						
						
							|  |     // NOTE: If uniform variable could not be found in the shader, function returns -1 | 
						
						
							|  |     int zoomLoc = GetShaderLocation(shader, "zoom"); | 
						
						
							|  |     int offsetLoc = GetShaderLocation(shader, "offset"); | 
						
						
							|  |     int maxIterationsLoc = GetShaderLocation(shader, "maxIterations"); | 
						
						
							|  | 
 | 
						
						
							|  |     // Upload the shader uniform values! | 
						
						
							|  |     SetShaderValue(shader, zoomLoc, &zoom, SHADER_UNIFORM_FLOAT); | 
						
						
							|  |     SetShaderValue(shader, offsetLoc, offset, SHADER_UNIFORM_VEC2); | 
						
						
							|  |     SetShaderValue(shader, maxIterationsLoc, &maxIterations, SHADER_UNIFORM_INT); | 
						
						
							|  | 
 | 
						
						
							|  |     bool showControls = true;           // Show controls | 
						
						
							|  |  | 
						
						
							|  |     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 | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |         bool updateShader = false; | 
						
						
							|  | 
 | 
						
						
							|  |         // Press [1 - 6] to reset c to a point of interest | 
						
						
							|  |         if (IsKeyPressed(KEY_ONE) || | 
						
						
							|  |             IsKeyPressed(KEY_TWO) || | 
						
						
							|  |             IsKeyPressed(KEY_THREE) || | 
						
						
							|  |             IsKeyPressed(KEY_FOUR) || | 
						
						
							|  |             IsKeyPressed(KEY_FIVE) || | 
						
						
							|  |             IsKeyPressed(KEY_SIX)) | 
						
						
							|  |         { | 
						
						
							|  |             int interestIndex = 0; | 
						
						
							|  |             if (IsKeyPressed(KEY_ONE)) interestIndex = 0; | 
						
						
							|  |             else if (IsKeyPressed(KEY_TWO)) interestIndex = 1; | 
						
						
							|  |             else if (IsKeyPressed(KEY_THREE)) interestIndex = 2; | 
						
						
							|  |             else if (IsKeyPressed(KEY_FOUR)) interestIndex = 3; | 
						
						
							|  |             else if (IsKeyPressed(KEY_FIVE)) interestIndex = 4; | 
						
						
							|  |             else if (IsKeyPressed(KEY_SIX)) interestIndex = 5; | 
						
						
							|  | 
 | 
						
						
							|  |             offset[0] = pointsOfInterest[interestIndex][0]; | 
						
						
							|  |             offset[1] = pointsOfInterest[interestIndex][1]; | 
						
						
							|  |             zoom = pointsOfInterest[interestIndex][2]; | 
						
						
							|  |             updateShader = true; | 
						
						
							|  |         } | 
						
						
							|  | 
 | 
						
						
							|  |         // If "R" is pressed, reset zoom and offset | 
						
						
							|  |         if (IsKeyPressed(KEY_R)) | 
						
						
							|  |         { | 
						
						
							|  |             offset[0] = startingOffset[0]; | 
						
						
							|  |             offset[1] = startingOffset[1]; | 
						
						
							|  |             zoom = startingZoom; | 
						
						
							|  |             updateShader = true; | 
						
						
							|  |         } | 
						
						
							|  | 
 | 
						
						
							|  |         if (IsKeyPressed(KEY_F1)) showControls = !showControls;  // Toggle whether or not to show controls | 
						
						
							|  |  | 
						
						
							|  | 		// Change number of max iterations with UP and DOWN keys | 
						
						
							|  | 		// WARNING: Increasing the number of max iterations greatly impacts performance | 
						
						
							|  |         if (IsKeyPressed(KEY_UP)) | 
						
						
							|  |         { | 
						
						
							|  |             maxIterationsMultiplier *= 1.4f; | 
						
						
							|  |             updateShader = true; | 
						
						
							|  |         } | 
						
						
							|  |         else if (IsKeyPressed(KEY_DOWN)) | 
						
						
							|  |         { | 
						
						
							|  |             maxIterationsMultiplier /= 1.4f; | 
						
						
							|  |             updateShader = true; | 
						
						
							|  |         } | 
						
						
							|  | 
 | 
						
						
							|  |         // If either left or right button is pressed, zoom in/out | 
						
						
							|  |         if (IsMouseButtonDown(MOUSE_BUTTON_LEFT) || IsMouseButtonDown(MOUSE_BUTTON_RIGHT)) | 
						
						
							|  |         { | 
						
						
							|  |             // Change zoom. If Mouse left -> zoom in. Mouse right -> zoom out | 
						
						
							|  |             zoom *= IsMouseButtonDown(MOUSE_BUTTON_LEFT)? zoomSpeed : (1.0f/zoomSpeed); | 
						
						
							|  | 
 | 
						
						
							|  |             const Vector2 mousePos = GetMousePosition(); | 
						
						
							|  |             Vector2 offsetVelocity; | 
						
						
							|  |             // Find the velocity at which to change the camera. Take the distance of the mouse | 
						
						
							|  |             // From the center of the screen as the direction, and adjust magnitude based on the current zoom | 
						
						
							|  |             offsetVelocity.x = (mousePos.x/(float)screenWidth - 0.5f)*offsetSpeedMul/zoom; | 
						
						
							|  |             offsetVelocity.y = (mousePos.y/(float)screenHeight - 0.5f)*offsetSpeedMul/zoom; | 
						
						
							|  | 
 | 
						
						
							|  |             // Apply move velocity to camera | 
						
						
							|  |             offset[0] += GetFrameTime()*offsetVelocity.x; | 
						
						
							|  |             offset[1] += GetFrameTime()*offsetVelocity.y; | 
						
						
							|  | 
 | 
						
						
							|  |             updateShader = true; | 
						
						
							|  |         } | 
						
						
							|  | 
 | 
						
						
							|  | 		// In case a parameter has been changed, update the shader values | 
						
						
							|  |         if (updateShader) | 
						
						
							|  | 		{ | 
						
						
							|  | 			// As we zoom in, increase the number of max iterations to get more detail | 
						
						
							|  |             // Aproximate formula, but it works-ish | 
						
						
							|  |             maxIterations = (int)(sqrtf(2.0f*sqrtf(fabsf(1.0f - sqrtf(37.5f*zoom))))*maxIterationsMultiplier); | 
						
						
							|  | 
 | 
						
						
							|  |             // Update the shader uniform values! | 
						
						
							|  |             SetShaderValue(shader, zoomLoc, &zoom, SHADER_UNIFORM_FLOAT); | 
						
						
							|  |             SetShaderValue(shader, offsetLoc, offset, SHADER_UNIFORM_VEC2); | 
						
						
							|  |             SetShaderValue(shader, maxIterationsLoc, &maxIterations, SHADER_UNIFORM_INT); | 
						
						
							|  |         } | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |  | 
						
						
							|  |         // Draw | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |         // Using a render texture to draw Mandelbrot set | 
						
						
							|  |         BeginTextureMode(target);       // Enable drawing to texture | 
						
						
							|  |             ClearBackground(BLACK);     // Clear the render texture | 
						
						
							|  |  | 
						
						
							|  |             // Draw a rectangle in shader mode to be used as shader canvas | 
						
						
							|  |             // NOTE: Rectangle uses font white character texture coordinates, | 
						
						
							|  |             // So shader can not be applied here directly because input vertexTexCoord | 
						
						
							|  |             // Do not represent full screen coordinates (space where want to apply shader) | 
						
						
							|  |             DrawRectangle(0, 0, GetScreenWidth(), GetScreenHeight(), BLACK); | 
						
						
							|  |         EndTextureMode(); | 
						
						
							|  | 
 | 
						
						
							|  |         BeginDrawing(); | 
						
						
							|  |             ClearBackground(BLACK);     // Clear screen background | 
						
						
							|  |  | 
						
						
							|  |             // Draw the saved texture and rendered mandelbrot set with shader | 
						
						
							|  |             // NOTE: We do not invert texture on Y, already considered inside shader | 
						
						
							|  |             BeginShaderMode(shader); | 
						
						
							|  |                 // WARNING: If FLAG_WINDOW_HIGHDPI is enabled, HighDPI monitor scaling should be considered | 
						
						
							|  |                 // When rendering the RenderTexture2D to fit in the HighDPI scaled Window | 
						
						
							|  |                 DrawTextureEx(target.texture, (Vector2){ 0.0f, 0.0f }, 0.0f, 1.0f, WHITE); | 
						
						
							|  |             EndShaderMode(); | 
						
						
							|  | 
 | 
						
						
							|  |             if (showControls) | 
						
						
							|  |             { | 
						
						
							|  |                 DrawText("Press Mouse buttons right/left to zoom in/out and move", 10, 15, 10, RAYWHITE); | 
						
						
							|  |                 DrawText("Press F1 to toggle these controls", 10, 30, 10, RAYWHITE); | 
						
						
							|  |                 DrawText("Press [1 - 6] to change point of interest", 10, 45, 10, RAYWHITE); | 
						
						
							|  |                 DrawText("Press UP | DOWN to change number of iterations", 10, 60, 10, RAYWHITE); | 
						
						
							|  |                 DrawText("Press R to recenter the camera", 10, 75, 10, RAYWHITE); | 
						
						
							|  |             } | 
						
						
							|  |         EndDrawing(); | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |     } | 
						
						
							|  | 
 | 
						
						
							|  |     // De-Initialization | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |     UnloadShader(shader);               // Unload shader | 
						
						
							|  |     UnloadRenderTexture(target);        // Unload render texture | 
						
						
							|  |  | 
						
						
							|  |     CloseWindow();                      // Close window and OpenGL context | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |  | 
						
						
							|  |     return 0; | 
						
						
							|  | }
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