xref: /aosp_15_r20/external/skia/tests/sksl/blend/BlendSaturation.metal (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1#include <metal_stdlib>
2#include <simd/simd.h>
3#ifdef __clang__
4#pragma clang diagnostic ignored "-Wall"
5#endif
6using namespace metal;
7constant const half sk_PrivkGuardedDivideEpsilon = half(false ? 1e-08 : 0.0);
8constant const half sk_PrivkMinNormalHalf = 6.10351562e-05h;
9struct Uniforms {
10    half4 src;
11    half4 dst;
12};
13struct Inputs {
14};
15struct Outputs {
16    half4 sk_FragColor [[color(0)]];
17};
18half blend_color_saturation_Qhh3(half3 color);
19half4 blend_hslc_h4h2h4h4(half2 flipSat, half4 src, half4 dst);
20half blend_color_saturation_Qhh3(half3 color) {
21    return max(max(color.x, color.y), color.z) - min(min(color.x, color.y), color.z);
22}
23half4 blend_hslc_h4h2h4h4(half2 flipSat, half4 src, half4 dst) {
24    half alpha = dst.w * src.w;
25    half3 sda = src.xyz * dst.w;
26    half3 dsa = dst.xyz * src.w;
27    half3 l = bool(flipSat.x) ? dsa : sda;
28    half3 r = bool(flipSat.x) ? sda : dsa;
29    if (bool(flipSat.y)) {
30        half _2_mn = min(min(l.x, l.y), l.z);
31        half _3_mx = max(max(l.x, l.y), l.z);
32        l = _3_mx > _2_mn ? ((l - _2_mn) * blend_color_saturation_Qhh3(r)) / (_3_mx - _2_mn) : half3(0.0h);
33        r = dsa;
34    }
35    half _4_lum = dot(half3(0.3h, 0.59h, 0.11h), r);
36    half3 _5_result = (_4_lum - dot(half3(0.3h, 0.59h, 0.11h), l)) + l;
37    half _6_minComp = min(min(_5_result.x, _5_result.y), _5_result.z);
38    half _7_maxComp = max(max(_5_result.x, _5_result.y), _5_result.z);
39    if (_6_minComp < 0.0h && _4_lum != _6_minComp) {
40        _5_result = _4_lum + (_5_result - _4_lum) * (_4_lum / (((_4_lum - _6_minComp) + sk_PrivkMinNormalHalf) + sk_PrivkGuardedDivideEpsilon));
41    }
42    if (_7_maxComp > alpha && _7_maxComp != _4_lum) {
43        _5_result = _4_lum + ((_5_result - _4_lum) * (alpha - _4_lum)) / (((_7_maxComp - _4_lum) + sk_PrivkMinNormalHalf) + sk_PrivkGuardedDivideEpsilon);
44    }
45    return half4((((_5_result + dst.xyz) - dsa) + src.xyz) - sda, (src.w + dst.w) - alpha);
46}
47fragment Outputs fragmentMain(Inputs _in [[stage_in]], constant Uniforms& _uniforms [[buffer(0)]], bool _frontFacing [[front_facing]], float4 _fragCoord [[position]]) {
48    Outputs _out;
49    (void)_out;
50    _out.sk_FragColor = blend_hslc_h4h2h4h4(half2(1.0h), _uniforms.src, _uniforms.dst);
51    return _out;
52}
53