|  | /******************************************************************************************* | 
						
						
							|  | * | 
						
						
							|  | *   raylib [shaders] example - spotlight rendering | 
						
						
							|  | * | 
						
						
							|  | *   Example complexity rating: [★★☆☆] 2/4 | 
						
						
							|  | * | 
						
						
							|  | *   Example originally created with raylib 2.5, last time updated with raylib 3.7 | 
						
						
							|  | * | 
						
						
							|  | *   Example contributed by Chris Camacho (@chriscamacho) 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) 2019-2025 Chris Camacho (@chriscamacho) and Ramon Santamaria (@raysan5) | 
						
						
							|  | * | 
						
						
							|  | ******************************************************************************************** | 
						
						
							|  | * | 
						
						
							|  | *   The shader makes alpha holes in the forground to give the appearance of a top | 
						
						
							|  | *   down look at a spotlight casting a pool of light... | 
						
						
							|  | * | 
						
						
							|  | *   The right hand side of the screen there is just enough light to see whats | 
						
						
							|  | *   going on without the spot light, great for a stealth type game where you | 
						
						
							|  | *   have to avoid the spotlights | 
						
						
							|  | * | 
						
						
							|  | *   The left hand side of the screen is in pitch dark except for where the spotlights are | 
						
						
							|  | * | 
						
						
							|  | *   Although this example doesn't scale like the letterbox example, you could integrate | 
						
						
							|  | *   the two techniques, but by scaling the actual colour of the render texture rather | 
						
						
							|  | *   than using alpha as a mask | 
						
						
							|  | * | 
						
						
							|  | ********************************************************************************************/ | 
						
						
							|  | 
 | 
						
						
							|  | #include "raylib.h" | 
						
						
							|  |  | 
						
						
							|  | #include "raymath.h" | 
						
						
							|  |  | 
						
						
							|  | #if defined(PLATFORM_DESKTOP) | 
						
						
							|  |     #define GLSL_VERSION            330 | 
						
						
							|  | #else   // PLATFORM_ANDROID, PLATFORM_WEB | 
						
						
							|  |     #define GLSL_VERSION            100 | 
						
						
							|  | #endif | 
						
						
							|  |  | 
						
						
							|  | #define MAX_SPOTS         3        // NOTE: It must be the same as define in shader | 
						
						
							|  | #define MAX_STARS       400 | 
						
						
							|  |  | 
						
						
							|  | //---------------------------------------------------------------------------------- | 
						
						
							|  | // Types and Structures Definition | 
						
						
							|  | //---------------------------------------------------------------------------------- | 
						
						
							|  | // Spot data | 
						
						
							|  | typedef struct Spot { | 
						
						
							|  |     Vector2 position; | 
						
						
							|  |     Vector2 speed; | 
						
						
							|  |     float inner; | 
						
						
							|  |     float radius; | 
						
						
							|  | 
 | 
						
						
							|  |     // Shader locations | 
						
						
							|  |     unsigned int positionLoc; | 
						
						
							|  |     unsigned int innerLoc; | 
						
						
							|  |     unsigned int radiusLoc; | 
						
						
							|  | } Spot; | 
						
						
							|  | 
 | 
						
						
							|  | // Stars in the star field have a position and velocity | 
						
						
							|  | typedef struct Star { | 
						
						
							|  |     Vector2 position; | 
						
						
							|  |     Vector2 speed; | 
						
						
							|  | } Star; | 
						
						
							|  | 
 | 
						
						
							|  | //-------------------------------------------------------------------------------------- | 
						
						
							|  | // Module Functions Declaration | 
						
						
							|  | //-------------------------------------------------------------------------------------- | 
						
						
							|  | static void UpdateStar(Star *star); | 
						
						
							|  | static void ResetStar(Star *star); | 
						
						
							|  | 
 | 
						
						
							|  | //------------------------------------------------------------------------------------ | 
						
						
							|  | // Program main entry point | 
						
						
							|  | //------------------------------------------------------------------------------------ | 
						
						
							|  | int main(void) | 
						
						
							|  | { | 
						
						
							|  |     // Initialization | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |     const int screenWidth = 800; | 
						
						
							|  |     const int screenHeight = 450; | 
						
						
							|  | 
 | 
						
						
							|  |     InitWindow(screenWidth, screenHeight, "raylib [shaders] example - spotlight rendering"); | 
						
						
							|  |     HideCursor(); | 
						
						
							|  | 
 | 
						
						
							|  |     Texture texRay = LoadTexture("resources/raysan.png"); | 
						
						
							|  | 
 | 
						
						
							|  |     Star stars[MAX_STARS] = { 0 }; | 
						
						
							|  | 
 | 
						
						
							|  |     for (int n = 0; n < MAX_STARS; n++) ResetStar(&stars[n]); | 
						
						
							|  | 
 | 
						
						
							|  |     // Progress all the stars on, so they don't all start in the centre | 
						
						
							|  |     for (int m = 0; m < screenWidth/2.0; m++) | 
						
						
							|  |     { | 
						
						
							|  |         for (int n = 0; n < MAX_STARS; n++) UpdateStar(&stars[n]); | 
						
						
							|  |     } | 
						
						
							|  | 
 | 
						
						
							|  |     int frameCounter = 0; | 
						
						
							|  | 
 | 
						
						
							|  |     // Use default vert shader | 
						
						
							|  |     Shader shdrSpot = LoadShader(0, TextFormat("resources/shaders/glsl%i/spotlight.fs", GLSL_VERSION)); | 
						
						
							|  | 
 | 
						
						
							|  |     // Get the locations of spots in the shader | 
						
						
							|  |     Spot spots[MAX_SPOTS]; | 
						
						
							|  | 
 | 
						
						
							|  |     for (int i = 0; i < MAX_SPOTS; i++) | 
						
						
							|  |     { | 
						
						
							|  |         char posName[32] = "spots[x].pos\0"; | 
						
						
							|  |         char innerName[32] = "spots[x].inner\0"; | 
						
						
							|  |         char radiusName[32] = "spots[x].radius\0"; | 
						
						
							|  | 
 | 
						
						
							|  |         posName[6] = '0' + i; | 
						
						
							|  |         innerName[6] = '0' + i; | 
						
						
							|  |         radiusName[6] = '0' + i; | 
						
						
							|  | 
 | 
						
						
							|  |         spots[i].positionLoc = GetShaderLocation(shdrSpot, posName); | 
						
						
							|  |         spots[i].innerLoc = GetShaderLocation(shdrSpot, innerName); | 
						
						
							|  |         spots[i].radiusLoc = GetShaderLocation(shdrSpot, radiusName); | 
						
						
							|  |     } | 
						
						
							|  | 
 | 
						
						
							|  |     // Tell the shader how wide the screen is so we can have | 
						
						
							|  |     // a pitch black half and a dimly lit half | 
						
						
							|  |     unsigned int wLoc = GetShaderLocation(shdrSpot, "screenWidth"); | 
						
						
							|  |     float sw = (float)GetScreenWidth(); | 
						
						
							|  |     SetShaderValue(shdrSpot, wLoc, &sw, SHADER_UNIFORM_FLOAT); | 
						
						
							|  | 
 | 
						
						
							|  |     // Randomize the locations and velocities of the spotlights | 
						
						
							|  |     // and initialize the shader locations | 
						
						
							|  |     for (int i = 0; i < MAX_SPOTS; i++) | 
						
						
							|  |     { | 
						
						
							|  |         spots[i].position.x = (float)GetRandomValue(64, screenWidth - 64); | 
						
						
							|  |         spots[i].position.y = (float)GetRandomValue(64, screenHeight - 64); | 
						
						
							|  |         spots[i].speed = (Vector2){ 0, 0 }; | 
						
						
							|  | 
 | 
						
						
							|  |         while ((fabs(spots[i].speed.x) + fabs(spots[i].speed.y)) < 2) | 
						
						
							|  |         { | 
						
						
							|  |             spots[i].speed.x = GetRandomValue(-400, 40)/25.0f; | 
						
						
							|  |             spots[i].speed.y = GetRandomValue(-400, 40)/25.0f; | 
						
						
							|  |         } | 
						
						
							|  | 
 | 
						
						
							|  |         spots[i].inner = 28.0f*(i + 1); | 
						
						
							|  |         spots[i].radius = 48.0f*(i + 1); | 
						
						
							|  | 
 | 
						
						
							|  |         SetShaderValue(shdrSpot, spots[i].positionLoc, &spots[i].position.x, SHADER_UNIFORM_VEC2); | 
						
						
							|  |         SetShaderValue(shdrSpot, spots[i].innerLoc, &spots[i].inner, SHADER_UNIFORM_FLOAT); | 
						
						
							|  |         SetShaderValue(shdrSpot, spots[i].radiusLoc, &spots[i].radius, SHADER_UNIFORM_FLOAT); | 
						
						
							|  |     } | 
						
						
							|  | 
 | 
						
						
							|  |     SetTargetFPS(60);               // Set  to run at 60 frames-per-second | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |  | 
						
						
							|  |     // Main game loop | 
						
						
							|  |     while (!WindowShouldClose())    // Detect window close button or ESC key | 
						
						
							|  |     { | 
						
						
							|  |         // Update | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |         frameCounter++; | 
						
						
							|  | 
 | 
						
						
							|  |         // Move the stars, resetting them if the go offscreen | 
						
						
							|  |         for (int n = 0; n < MAX_STARS; n++) UpdateStar(&stars[n]); | 
						
						
							|  | 
 | 
						
						
							|  |         // Update the spots, send them to the shader | 
						
						
							|  |         for (int i = 0; i < MAX_SPOTS; i++) | 
						
						
							|  |         { | 
						
						
							|  |             if (i == 0) | 
						
						
							|  |             { | 
						
						
							|  |                 Vector2 mp = GetMousePosition(); | 
						
						
							|  |                 spots[i].position.x = mp.x; | 
						
						
							|  |                 spots[i].position.y = screenHeight - mp.y; | 
						
						
							|  |             } | 
						
						
							|  |             else | 
						
						
							|  |             { | 
						
						
							|  |                 spots[i].position.x += spots[i].speed.x; | 
						
						
							|  |                 spots[i].position.y += spots[i].speed.y; | 
						
						
							|  | 
 | 
						
						
							|  |                 if (spots[i].position.x < 64) spots[i].speed.x = -spots[i].speed.x; | 
						
						
							|  |                 if (spots[i].position.x > (screenWidth - 64)) spots[i].speed.x = -spots[i].speed.x; | 
						
						
							|  |                 if (spots[i].position.y < 64) spots[i].speed.y = -spots[i].speed.y; | 
						
						
							|  |                 if (spots[i].position.y > (screenHeight - 64)) spots[i].speed.y = -spots[i].speed.y; | 
						
						
							|  |             } | 
						
						
							|  | 
 | 
						
						
							|  |             SetShaderValue(shdrSpot, spots[i].positionLoc, &spots[i].position.x, SHADER_UNIFORM_VEC2); | 
						
						
							|  |         } | 
						
						
							|  | 
 | 
						
						
							|  |         // Draw | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |         BeginDrawing(); | 
						
						
							|  | 
 | 
						
						
							|  |             ClearBackground(DARKBLUE); | 
						
						
							|  | 
 | 
						
						
							|  |             // Draw stars and bobs | 
						
						
							|  |             for (int n = 0; n < MAX_STARS; n++) | 
						
						
							|  |             { | 
						
						
							|  |                 // Single pixel is just too small these days! | 
						
						
							|  |                 DrawRectangle((int)stars[n].position.x, (int)stars[n].position.y, 2, 2, WHITE); | 
						
						
							|  |             } | 
						
						
							|  | 
 | 
						
						
							|  |             for (int i = 0; i < 16; i++) | 
						
						
							|  |             { | 
						
						
							|  |                 DrawTexture(texRay, | 
						
						
							|  |                     (int)((screenWidth/2.0f) + cos((frameCounter + i*8)/51.45f)*(screenWidth/2.2f) - 32), | 
						
						
							|  |                     (int)((screenHeight/2.0f) + sin((frameCounter + i*8)/17.87f)*(screenHeight/4.2f)), WHITE); | 
						
						
							|  |             } | 
						
						
							|  | 
 | 
						
						
							|  |             // Draw spot lights | 
						
						
							|  |             BeginShaderMode(shdrSpot); | 
						
						
							|  |                 // Instead of a blank rectangle you could render here | 
						
						
							|  |                 // a render texture of the full screen used to do screen | 
						
						
							|  |                 // scaling (slight adjustment to shader would be required | 
						
						
							|  |                 // to actually pay attention to the colour!) | 
						
						
							|  |                 DrawRectangle(0, 0, screenWidth, screenHeight, WHITE); | 
						
						
							|  |             EndShaderMode(); | 
						
						
							|  | 
 | 
						
						
							|  |             DrawFPS(10, 10); | 
						
						
							|  | 
 | 
						
						
							|  |             DrawText("Move the mouse!", 10, 30, 20, GREEN); | 
						
						
							|  |             DrawText("Pitch Black", (int)(screenWidth*0.2f), screenHeight/2, 20, GREEN); | 
						
						
							|  |             DrawText("Dark", (int)(screenWidth*.66f), screenHeight/2, 20, GREEN); | 
						
						
							|  | 
 | 
						
						
							|  |         EndDrawing(); | 
						
						
							|  |         //---------------------------------------------------------------------------------- | 
						
						
							|  |     } | 
						
						
							|  | 
 | 
						
						
							|  |     // De-Initialization | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |     UnloadTexture(texRay); | 
						
						
							|  |     UnloadShader(shdrSpot); | 
						
						
							|  | 
 | 
						
						
							|  |     CloseWindow();        // Close window and OpenGL context | 
						
						
							|  |     //-------------------------------------------------------------------------------------- | 
						
						
							|  |  | 
						
						
							|  |     return 0; | 
						
						
							|  | } | 
						
						
							|  | 
 | 
						
						
							|  | //-------------------------------------------------------------------------------------- | 
						
						
							|  | // Module Functions Definition | 
						
						
							|  | //-------------------------------------------------------------------------------------- | 
						
						
							|  | static void ResetStar(Star *star) | 
						
						
							|  | { | 
						
						
							|  |     star->position = (Vector2){ GetScreenWidth()/2.0f, GetScreenHeight()/2.0f }; | 
						
						
							|  |      | 
						
						
							|  |     star->speed.x = (float)GetRandomValue(-1000, 1000)/100.0f; | 
						
						
							|  |     star->speed.y = (float)GetRandomValue(-1000, 1000)/100.0f; | 
						
						
							|  | 
 | 
						
						
							|  |     while (!(fabs(star->speed.x) + (fabs(star->speed.y) > 1))) | 
						
						
							|  |     { | 
						
						
							|  |         star->speed.x = (float)GetRandomValue(-1000, 1000)/100.0f; | 
						
						
							|  |         star->speed.y = (float)GetRandomValue(-1000, 1000)/100.0f; | 
						
						
							|  |     }  | 
						
						
							|  | 
 | 
						
						
							|  |     star->position = Vector2Add(star->position, Vector2Multiply(star->speed, (Vector2){ 8.0f, 8.0f })); | 
						
						
							|  | } | 
						
						
							|  | 
 | 
						
						
							|  | static void UpdateStar(Star *star) | 
						
						
							|  | { | 
						
						
							|  |     star->position = Vector2Add(star->position, star->speed); | 
						
						
							|  | 
 | 
						
						
							|  |     if ((star->position.x < 0) || (star->position.x > GetScreenWidth()) || | 
						
						
							|  |         (star->position.y < 0) || (star->position.y > GetScreenHeight())) ResetStar(star); | 
						
						
							|  | }
 |