skia2/tests/sksl/blend/BlendSaturationStandaloneSettings.glsl
John Stiles c71922cd88 Reduce color fringes on blend_hue and blend_saturation.
Today I learned that `mix(a, b, 1)` can reduce precision. Ternaries do
not suffer from this problem.

Change-Id: I58814d00193ccbff53960030d163d31c49234f6c
Bug: skia:9320
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/528161
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
2022-04-07 13:39:08 +00:00

55 lines
2.4 KiB
GLSL

out vec4 sk_FragColor;
uniform vec4 src;
uniform vec4 dst;
vec3 blend_set_color_saturation_helper_Qh3h3h3(vec3 minMidMax, vec3 satColor) {
if (minMidMax.z > minMidMax.x) {
minMidMax.yz -= minMidMax.xx;
float sat = max(max(satColor.x, satColor.y), satColor.z) - min(min(satColor.x, satColor.y), satColor.z);
return vec3(0.0, sat * (minMidMax.y / minMidMax.z), sat);
} else {
return vec3(0.0);
}
}
vec4 blend_hslc_h4h4h4bb(vec4 src, vec4 dst, bool flip, bool saturate) {
float alpha = dst.w * src.w;
vec3 sda = src.xyz * dst.w;
vec3 dsa = dst.xyz * src.w;
vec3 l = flip ? dsa : sda;
vec3 r = flip ? sda : dsa;
if (saturate) {
vec3 _2_blend_set_color_saturation;
if (l.x <= l.y) {
if (l.y <= l.z) {
_2_blend_set_color_saturation = blend_set_color_saturation_helper_Qh3h3h3(l, r);
} else if (l.x <= l.z) {
_2_blend_set_color_saturation = blend_set_color_saturation_helper_Qh3h3h3(l.xzy, r).xzy;
} else {
_2_blend_set_color_saturation = blend_set_color_saturation_helper_Qh3h3h3(l.zxy, r).yzx;
}
} else if (l.x <= l.z) {
_2_blend_set_color_saturation = blend_set_color_saturation_helper_Qh3h3h3(l.yxz, r).yxz;
} else if (l.y <= l.z) {
_2_blend_set_color_saturation = blend_set_color_saturation_helper_Qh3h3h3(l.yzx, r).zxy;
} else {
_2_blend_set_color_saturation = blend_set_color_saturation_helper_Qh3h3h3(l.zyx, r).zyx;
}
l = _2_blend_set_color_saturation;
r = dsa;
}
float _3_lum = dot(vec3(0.30000001192092896, 0.5899999737739563, 0.10999999940395355), r);
vec3 _4_result = (_3_lum - dot(vec3(0.30000001192092896, 0.5899999737739563, 0.10999999940395355), l)) + l;
float _5_minComp = min(min(_4_result.x, _4_result.y), _4_result.z);
float _6_maxComp = max(max(_4_result.x, _4_result.y), _4_result.z);
if (_5_minComp < 0.0 && _3_lum != _5_minComp) {
_4_result = _3_lum + (_4_result - _3_lum) * (_3_lum / (_3_lum - _5_minComp));
}
if (_6_maxComp > alpha && _6_maxComp != _3_lum) {
_4_result = _3_lum + ((_4_result - _3_lum) * (alpha - _3_lum)) / (_6_maxComp - _3_lum);
}
return vec4((((_4_result + dst.xyz) - dsa) + src.xyz) - sda, (src.w + dst.w) - alpha);
}
void main() {
sk_FragColor = blend_hslc_h4h4h4bb(src, dst, true, true);
}