| /******************************************************************************************* | |
| * | |
| *   raylib example - particles trail blending | |
| * | |
| *   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) | |
| * | |
| ********************************************************************************************/ | |
| 
 | |
| #include "raylib.h" | |
|  | |
| #define MAX_PARTICLES 200 | |
|  | |
| // Particle structure with basic data | |
| typedef struct { | |
|     Vector2 position; | |
|     Color color; | |
|     float alpha; | |
|     float size; | |
|     float rotation; | |
|     bool active;        // NOTE: Use it to activate/deactive particle | |
| } Particle; | |
| 
 | |
| int main() | |
| { | |
|     // Initialization | |
|     //-------------------------------------------------------------------------------------- | |
|     int screenWidth = 800; | |
|     int screenHeight = 450; | |
| 
 | |
|     InitWindow(screenWidth, screenHeight, "raylib [textures] example - particles trail blending"); | |
|      | |
|     // Particles pool, reuse them! | |
|     Particle mouseTail[MAX_PARTICLES];  | |
|      | |
|     // Initialize particles | |
|     for (int i = 0; i < MAX_PARTICLES; i++) | |
|     { | |
|         mouseTail[i].position = (Vector2){ 0, 0 }; | |
|         mouseTail[i].color = (Color){ GetRandomValue(0, 255), GetRandomValue(0, 255), GetRandomValue(0, 255), 255 }; | |
|         mouseTail[i].alpha = 1.0f; | |
|         mouseTail[i].size = (float)GetRandomValue(1, 30)/20; | |
|         mouseTail[i].rotation = GetRandomValue(0, 360); | |
|         mouseTail[i].active = false; | |
|     } | |
|      | |
|     float gravity = 3; | |
| 
 | |
|     Texture2D smoke = LoadTexture("resources/smoke.png"); | |
|      | |
|     int blending = BLEND_ALPHA; | |
|      | |
|     SetTargetFPS(60); | |
|     //-------------------------------------------------------------------------------------- | |
|  | |
|     // Main game loop | |
|     while (!WindowShouldClose())    // Detect window close button or ESC key | |
|     { | |
|         // Update | |
|         //---------------------------------------------------------------------------------- | |
|          | |
|         // Activate one particle every frame and Update active particles | |
|         // NOTE: Particles initial position should be mouse position when activated | |
|         // NOTE: Particles fall down with gravity and rotation... and disappear after 2 seconds (alpha = 0) | |
|         // NOTE: When a particle disappears, active = false and it can be reused. | |
|         for (int i = 0; i < MAX_PARTICLES; i++) | |
|         { | |
|             if (!mouseTail[i].active) | |
|             { | |
|                 mouseTail[i].active = true; | |
|                 mouseTail[i].alpha = 1.0f; | |
|                 mouseTail[i].position = GetMousePosition(); | |
|                 i = MAX_PARTICLES; | |
|             } | |
|         } | |
| 
 | |
|         for (int i = 0; i < MAX_PARTICLES; i++) | |
|         { | |
|             if (mouseTail[i].active) | |
|             { | |
|                 mouseTail[i].position.y += gravity; | |
|                 mouseTail[i].alpha -= 0.01f; | |
|                  | |
|                 if (mouseTail[i].alpha <= 0.0f) mouseTail[i].active = false; | |
|                  | |
|                 mouseTail[i].rotation += 5; | |
|             } | |
|         } | |
|          | |
|         if (IsKeyPressed(KEY_SPACE)) | |
|         { | |
|             if (blending == BLEND_ALPHA) blending = BLEND_ADDITIVE; | |
|             else blending = BLEND_ALPHA; | |
|         } | |
|         //---------------------------------------------------------------------------------- | |
|  | |
|         // Draw | |
|         //---------------------------------------------------------------------------------- | |
|         BeginDrawing(); | |
| 
 | |
|             ClearBackground(DARKGRAY); | |
|              | |
|             SetBlendMode(blending); | |
| 
 | |
|             // Draw active particles | |
|             for (int i = 0; i < MAX_PARTICLES; i++) | |
|             { | |
|                 if (mouseTail[i].active) DrawTexturePro(smoke, (Rectangle){ 0, 0, smoke.width, smoke.height },  | |
|                                                        (Rectangle){ mouseTail[i].position.x, mouseTail[i].position.y, smoke.width*mouseTail[i].size, smoke.height*mouseTail[i].size }, | |
|                                                        (Vector2){ smoke.width*mouseTail[i].size/2, smoke.height*mouseTail[i].size/2 }, mouseTail[i].rotation, | |
|                                                        Fade(mouseTail[i].color, mouseTail[i].alpha)); | |
|             } | |
|              | |
|             DrawText("PRESS SPACE to CHANGE BLENDING MODE", 180, 20, 20, RAYWHITE); | |
|              | |
|             if (blending == BLEND_ALPHA) DrawText("ALPHA BLENDING", 290, screenHeight - 40, 20, RAYWHITE); | |
|             else DrawText("ADDITIVE BLENDING", 280, screenHeight - 40, 20, RAYWHITE); | |
|              | |
|         EndDrawing(); | |
|         //---------------------------------------------------------------------------------- | |
|     } | |
| 
 | |
|     // De-Initialization | |
|     //-------------------------------------------------------------------------------------- | |
|     UnloadTexture(smoke); | |
|      | |
|     CloseWindow();        // Close window and OpenGL context | |
|     //-------------------------------------------------------------------------------------- | |
|  | |
|     return 0; | |
| } |