REVIEWED: shaders_spotlight example

It seems something is not working properly...

examples/shaders/resources/shaders/glsl330/spotlight.fs

@@ -1,27 +1,29 @@
 #version 330
 
+// Input vertex attributes (from vertex shader)
+in vec2 fragTexCoord;
+in vec4 fragColor;
+
 // Output fragment color
 out vec4 finalColor;
 
-#define     MAX_SPOTS			4
-#define		RADIUS				256
-#define		INNER				200
+// NOTE: Add here your custom variables
 
-// Inputs
-// array of spotlight positions
-uniform vec2 spots[MAX_SPOTS];
+#define     MAX_SPOTS			2
+#define		RADIUS				128
+#define		INNER				96
 
-uniform float screenWidth; // width of the screen
+uniform vec2 spots[MAX_SPOTS];      // Spotlight positions array
+uniform float screenWidth;          // Width of the screen
 
 void main()
 {
-
-	float alpha;
-	// get the position of the current fragment (screen coordinates!)
+	float alpha = 0.0;
+    
+	// Get the position of the current fragment (screen coordinates!)
 	vec2 pos = vec2(gl_FragCoord.x, gl_FragCoord.y);
-
 	
-	// find out which spotlight is nearest
+	// Find out which spotlight is nearest
 	float d = 65000; // some high value
 	float di = 0;
 
@@ -32,22 +34,16 @@ void main()
     }
     
     // d now equals distance to nearest spot...
-    if (d > RADIUS) {
-		alpha = 1.0;
-	} else {
-		if (d < INNER) {
-			alpha = 0.0;
-		} else {
-			alpha = (d - INNER) / (RADIUS - INNER);
-		}
+    if (d > RADIUS) alpha = 1.0;
+	else
+    {
+		if (d < INNER) alpha = 0.0;
+		else alpha = (d - INNER)/(RADIUS - INNER);
 	}
 	
-	// right hand side of screen is dimly lit, could make the
-	// threshold value user definable.
-	if (pos.x>screenWidth/2.0 && alpha >0.9) {
-		alpha = 0.9;
-	}
+	// Right hand side of screen is dimly lit, 
+    // could make the threshold value user definable
+	if ((pos.x > screenWidth/2.0) && (alpha > 0.9)) alpha = 0.9;
 
-	// could make the black out colour user definable...
-    finalColor = vec4( 0, 0, 0, alpha);
+    finalColor = vec4(0, 0, 0, alpha);
 }

examples/shaders/shaders_spotlight.c

@@ -1,107 +1,91 @@
-/*
- * Copyright (c) 2019 Chris Camacho (codifies -  http://bedroomcoders.co.uk/)
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- *
- */
- 
-/* The shader makes alpha holes in the forground to give the apearance 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 <stddef.h>
-#include <stdint.h>
+/*******************************************************************************************
+*
+*   raylib [shaders] example - Simple shader mask
+*
+*   This example has been created using raylib 2.5 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Example contributed by Chris Camacho (@codifies -  http://bedroomcoders.co.uk/) 
+*   and reviewed by Ramon Santamaria (@raysan5)
+*
+*   Copyright (c) 2019 Chris Camacho (@codifies) and Ramon Santamaria (@raysan5)
+*
+********************************************************************************************
+*
+*   The shader makes alpha holes in the forground to give the apearance 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"
 
+#include <stddef.h>
+#include <stdint.h>
+
 #if defined(PLATFORM_DESKTOP)
     #define GLSL_VERSION            330
 #else   // PLATFORM_RPI, PLATFORM_ANDROID, PLATFORM_WEB
     #define GLSL_VERSION            100
 #endif
 
-// single digit only!
-#define MAXSPOT 4
+#define MAXSPOT           2
+#define numStars        400
 
-#define numStars 400
-
-#define screenWidth 1280
-#define screenHeight 720
-
-// the stars in the star field have a position and velocity
-typedef struct star {
+// Stars in the star field have a position and velocity
+typedef struct Star {
     Vector2 pos;
     Vector2 vel;
-} star;
+} Star;
 
-
-void updateStar(star *s);
-void resetStar(star *s);
+void UpdateStar(Star *s);
+void ResetStar(Star *s);
 
 int main(void)
 {
     // Initialization
     //--------------------------------------------------------------------------------------
-    star stars[numStars];
+    const int screenWidth = 800;
+    const int screenHeight = 450;
 
-    for (int n=0; n < numStars; n++) {
-        resetStar(&stars[n]);
-    }
+    InitWindow(screenWidth, screenHeight, "raylib - shader spotlight");
 
-    // 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<numStars; n++) {
-            updateStar(&stars[n]);
-        }
-    }
+    Texture texRay = LoadTexture("resources/raysan.png");
+    
+    Star stars[numStars] = { 0 };
 
-    //SetConfigFlags(FLAG_FULLSCREEN_MODE);
-    InitWindow(screenWidth, screenHeight, "raylib - test");
+    for (int n = 0; n < numStars; n++) ResetStar(&stars[n]);
 
-    Texture rayTex = LoadTexture("resources/raysan.png"); 
+    // 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 < numStars; n++) UpdateStar(&stars[n]);
+    }
 
-    // frame counter
-    int frame = 0;
+    int frameCounter = 0;
 
-    unsigned int spotLoc[MAXSPOT]; // shader locations    
+    unsigned int spotLoc[MAXSPOT];  // shader locations    
  
-    Vector2 spotPos[MAXSPOT];  // position and velocity
+    Vector2 spotPos[MAXSPOT];       // position and velocity
     Vector2 spotVel[MAXSPOT];
        
-    // use default vert shader
+    // Use default vert shader
     Shader spotShader = LoadShader(0, FormatText("resources/shaders/glsl%i/spotlight.fs", GLSL_VERSION));
     
-	// get the locations of spots in the shader
+	// Get the locations of spots in the shader
     char spotName[32] = "spots[x]\0";
-    for (int i = 0; i<MAXSPOT; i++) {
+    for (int i = 0; i < MAXSPOT; i++) 
+    {
 		spotName[6] = '0' + i;
 		spotLoc[i] = GetShaderLocation(spotShader, spotName);
 	}
@@ -110,47 +94,47 @@ int main(void)
 	// a pitch black half and a dimly lit half.
 	{
 		unsigned int wLoc = GetShaderLocation(spotShader, "screenWidth");
-		float sw = screenWidth;
+		float sw = (float)GetScreenWidth();
 		SetShaderValue(spotShader, wLoc, &sw, UNIFORM_FLOAT);
 	}
 
     // randomise the locations and velocities of the spotlights
-    for (int i=0; i<MAXSPOT; i++) {
-		spotPos[i].x = GetRandomValue(128, screenWidth-128);
-		spotPos[i].y = GetRandomValue(128, screenHeight-128);
-		spotVel[i] = (Vector2){0, 0};
-		while (fabs(spotVel[i].x)+fabs(spotVel[i].y)<2) {
-			spotVel[i].x = GetRandomValue(-40,40)/10.0;
-			spotVel[i].y = GetRandomValue(-40,40)/10.0;
+    for (int i = 0; i < MAXSPOT; i++)
+    {
+		spotPos[i].x = GetRandomValue(64, screenWidth - 64);
+		spotPos[i].y = GetRandomValue(64, screenHeight - 64);
+		spotVel[i] = (Vector2){ 0, 0 };
+        
+		while ((fabs(spotVel[i].x) + fabs(spotVel[i].y)) < 2)
+        {
+			spotVel[i].x = GetRandomValue(-40, 40)/10.0;
+			spotVel[i].y = GetRandomValue(-40, 40)/10.0;
 		}
 	}
-  
 
     SetTargetFPS(60);               // Set  to run at 60 frames-per-second
     //--------------------------------------------------------------------------------------
+    
     // Main game loop
     while (!WindowShouldClose())    // Detect window close button or ESC key
     {
         // Update
         //----------------------------------------------------------------------------------
+        frameCounter++;
 
-        frame ++;
-
-		// move the stars, resetting them if the go offscreen
-        for (int n=0; n<numStars; n++) {
-            updateStar(&stars[n]);
-        }
-
-		// update the spots, send them to the shader
-		for (int i=0; i<MAXSPOT; i++) {
+		// Move the stars, resetting them if the go offscreen
+        for (int n = 0; n < numStars; n++) UpdateStar(&stars[n]);
 
+		// Update the spots, send them to the shader
+		for (int i = 0; i < MAXSPOT; i++)
+        {
 			spotPos[i].x += spotVel[i].x;					
 			spotPos[i].y += spotVel[i].y;
 			
-			if (spotPos[i].x < 128) spotVel[i].x = -spotVel[i].x;					
-			if (spotPos[i].x > screenWidth-128) spotVel[i].x = -spotVel[i].x;					
-			if (spotPos[i].y < 128) spotVel[i].y = -spotVel[i].y;					
-			if (spotPos[i].y > screenHeight-128) spotVel[i].y = -spotVel[i].y;
+			if (spotPos[i].x < 64) spotVel[i].x = -spotVel[i].x;					
+			if (spotPos[i].x > screenWidth - 64) spotVel[i].x = -spotVel[i].x;					
+			if (spotPos[i].y < 64) spotVel[i].y = -spotVel[i].y;					
+			if (spotPos[i].y > screenHeight - 64) spotVel[i].y = -spotVel[i].y;
 			
 			SetShaderValue(spotShader, spotLoc[i], &spotPos[i].x, UNIFORM_VEC2);				
 		}
@@ -159,22 +143,24 @@ int main(void)
         //----------------------------------------------------------------------------------
         BeginDrawing();
 
-            ClearBackground((Color){0,32,128,255});
+            ClearBackground(DARKBLUE);
 
-			// stars and bobs
-            for (int n=0; n<numStars; n++) {
-				// single pixel is just too small these days!
+			// Draw stars and bobs
+            for (int n = 0; n < numStars; n++)
+            {
+				// Single pixel is just too small these days!
                 DrawRectangle(stars[n].pos.x, stars[n].pos.y, 2, 2, WHITE);
             }
 
-            for (int i=0; i<16; i++) {
-                DrawTexture(rayTex,
-                    (screenWidth/2.0)+cos((frame+i*8)/51.45)*(screenWidth/2.2)-32,
-                    (screenHeight/2.0)+sin((frame+i*8)/17.87)*(screenHeight/4.2),
+            for (int i = 0; i < 16; i++)
+            {
+                DrawTexture(texRay,
+                    (screenWidth/2.0) + cos((frameCounter + i*8)/51.45f)*(screenWidth/2.2) - 32,
+                    (screenHeight/2.0) + sin((frameCounter + i*8)/17.87f)*(screenHeight/4.2),
                     WHITE);
             }
 
-			// spot lights
+			// Draw spot lights
 			BeginShaderMode(spotShader);
 				// instead of a blank rectangle you could render here
 				// a render texture of the full screen used to do screen
@@ -185,15 +171,13 @@ int main(void)
 
             DrawFPS(10, 10);
 
-
         EndDrawing();
         //----------------------------------------------------------------------------------
     }
 
     // De-Initialization
     //--------------------------------------------------------------------------------------
-
-    UnloadTexture(rayTex);
+    UnloadTexture(texRay);
 
     CloseWindow();        // Close window and OpenGL context
     //--------------------------------------------------------------------------------------
@@ -202,23 +186,28 @@ int main(void)
 }
 
 
-void resetStar(star *s)
+void ResetStar(Star *s)
 {
-    (*s).pos = (Vector2){screenWidth/2.0, screenHeight/2.0 };
-    do {
-        (*s).vel.x = (float)GetRandomValue(-1000,1000) / 100.0;
-        (*s).vel.y = (float)GetRandomValue(-1000,1000) / 100.0;
-    } while (!(fabs((*s).vel.x)+fabs((*s).vel.y)>1));
-    (*s).pos = Vector2Add( (*s).pos,
-                    Vector2MultiplyV((*s).vel,(Vector2){8,8} ));
+    s->pos = (Vector2){ GetScreenWidth()/2.0f, GetScreenHeight()/2.0f };
+    
+    do
+    {
+        s->vel.x = (float)GetRandomValue(-1000, 1000)/100.0f;
+        s->vel.y = (float)GetRandomValue(-1000, 1000)/100.0f;
+        
+    } while (!(fabs(s->vel.x) + fabs(s->vel.y) > 1));
+    
+    s->pos = Vector2Add(s->pos, Vector2MultiplyV(s->vel, (Vector2){ 8, 8 }));
 }
 
-void updateStar(star *s)
+void UpdateStar(Star *s)
 {
-    (*s).pos = Vector2Add((*s).pos, (*s).vel);
-    if ((*s).pos.x < 0 || (*s).pos.x > screenWidth ||
-        (*s).pos.y < 0 || (*s).pos.y > screenHeight) {
-            resetStar(s);
+    s->pos = Vector2Add(s->pos, s->vel);
+    
+    if (s->pos.x < 0 || s->pos.x > GetScreenWidth() ||
+        s->pos.y < 0 || s->pos.y > GetScreenHeight())
+    {
+        ResetStar(s);
     }
 }