xref: /OK3568_Linux_fs/app/forlinx/flapp/src/plugins/imxwayland/qmlvideofx/shaders/posterize.fsh (revision 4882a59341e53eb6f0b4789bf948001014eff981)
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33
34// Based on http://www.geeks3d.com/20091027/shader-library-posterization-post-processing-effect-glsl/
35
36uniform float dividerValue;
37uniform float gamma;
38uniform float numColors;
39
40uniform sampler2D source;
41uniform lowp float qt_Opacity;
42varying vec2 qt_TexCoord0;
43
44void main()
45{
46    vec2 uv = qt_TexCoord0.xy;
47    vec4 c = vec4(0.0);
48    if (uv.x < dividerValue) {
49        vec3 x = texture2D(source, uv).rgb;
50        x = pow(x, vec3(gamma, gamma, gamma));
51        x = x * numColors;
52        x = floor(x);
53        x = x / numColors;
54        x = pow(x, vec3(1.0/gamma));
55        c = vec4(x, 1.0);
56    } else {
57        c = texture2D(source, uv);
58    }
59    gl_FragColor = qt_Opacity * c;
60}
61