Vignette effect

shaders/combine.f.glsl

@@ -5,22 +5,54 @@
 layout( location = 0 ) uniform sampler2D u_MainInput;
 layout( location = 1 ) uniform sampler2D u_BlurInput;
 layout( location = 2 ) uniform vec2 u_OutputSize;
-layout( location = 3 ) uniform vec2 u_Parameters;
+layout( location = 3 ) uniform vec2 u_Bloom;
 
-layout( location = 0 ) out vec3 color;
+// Vignette parameters
+// 1.x = shape multiplier
+// 1.y = shape power
+// 1.z = aspect ratio
+// 1.w = reverse power multiplier
+// 2.x = apply base
+// 2.y = apply max
+layout( location = 4 ) uniform vec4 u_Vignette1;
+layout( location = 5 ) uniform vec2 u_Vignette2;
+
+#define uVigShapeMul (u_Vignette1.x)
+#define uVigShapePow (u_Vignette1.y)
+#define uVigAspect (u_Vignette1.z)
+#define uVigShapeReverse (u_Vignette1.w)
+#define uVigApplyBase (u_Vignette2.x)
+#define uVigApplyMax (u_Vignette2.y)
+
+
+layout( location = 0 ) out vec3 o_Color;
 
 void main( void )
 {
-	vec2 tmp = gl_FragCoord.xy / u_OutputSize;
-	float f = u_Parameters.x;
-	color = textureLod( u_MainInput , tmp , 0 ).rgb;
+	vec2 pos = gl_FragCoord.xy / u_OutputSize;
+	float f = u_Bloom.x;
+	o_Color = textureLod( u_MainInput , pos , 0 ).rgb;
+
+	// Bloom
 	vec3 bloom = vec3( 0 );
 	for ( int i = 0 ; i < 6 ; i ++ ) {
-		bloom += f * textureLod( u_BlurInput , tmp , i ).rgb;
-		f = pow( f , u_Parameters.y + 1 );
+		bloom += f * textureLod( u_BlurInput , pos , i ).rgb;
+		f = pow( f , u_Bloom.y + 1 );
 	}
-	color = color + bloom / 2.2;
+	o_Color = o_Color + bloom / 2.2;
 
-	color = color / ( color + 1. );
-	color = pow( color , vec3( 1.0 / 2.2 ) );
+	// Vignette
+	vec2 vShape = pow( abs( pos * 2 - 1 ) * uVigShapeMul ,
+		vec2( uVigShapePow ) );
+	float vignette = 1 - pow(
+		2 * ( uVigAspect * vShape.x + ( 1 - uVigAspect) * vShape.y ) ,
+		1 / ( uVigShapePow * uVigShapeReverse ) );
+	o_Color *= uVigApplyBase + smoothstep(
+		uVigApplyBase , uVigApplyBase + uVigApplyMax , vignette );
+
+	// Reinhart
+	o_Color = o_Color / ( o_Color + 1. );
+
+	// Gamma
+	o_Color = pow( o_Color , vec3( 1.0 / 2.2 ) );
 }