44 lines
1.0 KiB
GLSL
44 lines
1.0 KiB
GLSL
precision highp float;
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uniform sampler2D texture;
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uniform sampler2D pixel_layout;
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uniform mat3 color_matrix;
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uniform vec2 pixel_size;
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// varying vec2 uv1;
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// varying vec2 uv2;
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varying vec2 top_left_uv;
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varying vec2 top_right_uv;
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varying vec2 bottom_left_uv;
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varying vec2 bottom_right_uv;
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varying vec2 half_pixel_coord;
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#define fetch(p) texture2D(texture, p).r
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void main() {
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vec4 pixels = vec4(
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fetch(top_left_uv),
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fetch(top_right_uv),
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fetch(bottom_right_uv),
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fetch(bottom_left_uv));
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vec2 arrangement = floor(half_pixel_coord);
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vec2 is_bottom_left = step(1.0, arrangement);
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// vec3 color = mix(
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// mix(pixels.xyz, pixels.yzw, is_bottom_left.y),
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// mix(pixels.wzy, pixels.zyx, is_bottom_left.y),
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// is_bottom_left.x);
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vec3 color = pixels.zyx;
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// Fast SRGB estimate. See https://mimosa-pudica.net/fast-gamma/
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vec3 srgb_color = (vec3(1.138) * inversesqrt(color) - vec3(0.138)) * color;
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// Slow SRGB estimate
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// vec3 srgb_color = pow(color, vec3(1.0 / 2.2));
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gl_FragColor = vec4(color_matrix * srgb_color, 0);
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}
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