ProjectArcade

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// Retro (CRT) shader, created to use in PPSSPP.
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#ifdef GL_ES
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precision mediump float;
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precision mediump int;
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#endif
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uniform sampler2D sampler0;
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varying vec2 v_texcoord0;
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uniform vec4 u_time;
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uniform vec4 u_setting;
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void main()
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{
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    // scanlines
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    int vPos = int( ( v_texcoord0.y + u_time.x * u_setting.x * 0.5 ) * 272.0 );
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    float line_intensity = mod( float(vPos), 2.0 );
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    // color shift
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    float off = line_intensity * 0.0005;
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    vec2 shift = vec2( off, 0 );
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    // shift R and G channels to simulate NTSC color bleed
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    vec2 colorShift = vec2( 0.001, 0 );
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    float r = texture2D( sampler0, v_texcoord0 + colorShift + shift ).x;
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    float g = texture2D( sampler0, v_texcoord0 - colorShift + shift ).y;
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    float b = texture2D( sampler0, v_texcoord0 ).z;
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    vec4 c = vec4( r, g * 0.99, b, 1.0 ) * clamp( line_intensity, 0.85, 1.0 );
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    if (u_setting.x > 0.0) {
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        float rollbar = sin( ( v_texcoord0.y + u_time.x * u_setting.x ) * 4.0 );
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        c += rollbar * 0.02;
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    }
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    gl_FragColor.rgba = c;
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}
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