73be6657ea
This makes it possible to adjust both brightness and opacity at the same time with one multiplication in the fragment shader.
28 lines
647 B
GLSL
28 lines
647 B
GLSL
uniform sampler2D sample;
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uniform vec4 modulation;
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uniform float textureWidth;
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uniform float textureHeight;
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uniform float saturation;
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uniform int u_forceAlpha;
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varying vec2 varyingTexCoords;
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void main()
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{
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vec4 tex = texture2D(sample, varyingTexCoords);
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if (u_forceAlpha > 0) {
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tex.a = 1.0;
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}
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if (saturation != 1.0) {
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vec3 desaturated = tex.rgb * vec3( 0.30, 0.59, 0.11 );
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desaturated = vec3( dot( desaturated, tex.rgb ));
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tex.rgb = tex.rgb * vec3( saturation ) + desaturated * vec3( 1.0 - saturation );
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}
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tex *= modulation;
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tex.rgb = vec3(1.0) - tex.rgb;
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gl_FragColor = tex;
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}
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