shaders: add skia shaders

Add shaders extracted from skia's unit tests[1]

[1] https://skia.org/dev/testing/testing

1 files changed, 157 insertions, 0 deletions

diff --git a/shaders/skia/271-3.shader_test b/shaders/skia/271-3.shader_test
new file mode 100644
index 0000000..856d608
--- /dev/null
+++ b/shaders/skia/271-3.shader_test
@@ -0,0 +1,157 @@
+[require]
+GLSL >= 1.40
+
+[fragment shader]
+#version 140
+
+out vec4 sk_FragColor;
+uniform vec2 ubaseFrequency_Stage1_c0_c0;
+uniform vec4 uleftBorderColor_Stage2_c1_c0;
+uniform vec4 urightBorderColor_Stage2_c1_c0;
+uniform float ubias_Stage2_c1_c0_c0_c0;
+uniform float uscale_Stage2_c1_c0_c0_c0;
+uniform vec4 uscale01_Stage2_c1_c0_c1_c0;
+uniform vec4 ubias01_Stage2_c1_c0_c1_c0;
+uniform vec4 uscale23_Stage2_c1_c0_c1_c0;
+uniform vec4 ubias23_Stage2_c1_c0_c1_c0;
+uniform float uthreshold_Stage2_c1_c0_c1_c0;
+uniform sampler2D uTextureSampler_0_Stage1;
+uniform sampler2D uTextureSampler_1_Stage1;
+noperspective in vec4 vcolor_Stage0;
+noperspective in vec2 vTransformedCoords_0_Stage0;
+noperspective in vec2 vTransformedCoords_1_Stage0;
+noperspective in float vinCoverage_Stage0;
+float perlinnoise_Stage1_c0_c0(float chanCoord, vec2 noiseVec) {
+    vec4 floorVal;
+    floorVal.xy = floor(noiseVec);
+    floorVal.zw = floorVal.xy + vec2(1.0);
+    vec2 fractVal = fract(noiseVec);
+    vec2 noiseSmooth = (fractVal * fractVal) * (vec2(3.0) - vec2(2.0) * fractVal);
+    floorVal = fract(floor(mod(floorVal, 256.0)) / vec4(256.0));
+    vec2 latticeIdx;
+    latticeIdx.x = texture(uTextureSampler_0_Stage1, vec2(floorVal.x, 0.5)).x;
+    latticeIdx.y = texture(uTextureSampler_0_Stage1, vec2(floorVal.z, 0.5)).x;
+    vec4 bcoords = fract(latticeIdx.xyxy + floorVal.yyww);
+    vec2 uv;
+    vec4 lattice = texture(uTextureSampler_1_Stage1, vec2(bcoords.x, chanCoord)).zyxw;
+    uv.x = dot((lattice.yw + lattice.xz * vec2(0.00390625)) * vec2(2.0) - vec2(1.0), fractVal);
+    fractVal.x -= 1.0;
+    lattice = texture(uTextureSampler_1_Stage1, vec2(bcoords.y, chanCoord)).zyxw;
+    uv.y = dot((lattice.yw + lattice.xz * vec2(0.00390625)) * vec2(2.0) - vec2(1.0), fractVal);
+    vec2 ab;
+    ab.x = mix(uv.x, uv.y, noiseSmooth.x);
+    fractVal.y -= 1.0;
+    lattice = texture(uTextureSampler_1_Stage1, vec2(bcoords.w, chanCoord)).zyxw;
+    uv.y = dot((lattice.yw + lattice.xz * vec2(0.00390625)) * vec2(2.0) - vec2(1.0), fractVal);
+    fractVal.x += 1.0;
+    lattice = texture(uTextureSampler_1_Stage1, vec2(bcoords.z, chanCoord)).zyxw;
+    uv.x = dot((lattice.yw + lattice.xz * vec2(0.00390625)) * vec2(2.0) - vec2(1.0), fractVal);
+    ab.y = mix(uv.x, uv.y, noiseSmooth.x);
+    return mix(ab.x, ab.y, noiseSmooth.y);
+}
+vec4 PerlinNoise_Stage1_c0_c0(vec4 _input) {
+    vec4 _output;
+    vec2 noiseVec = floor(vTransformedCoords_0_Stage0) * ubaseFrequency_Stage1_c0_c0;
+    _output = vec4(0.0);
+    float ratio = 1.0;
+    for (int octave = 0;octave < 6; ++octave) {
+        _output += vec4(perlinnoise_Stage1_c0_c0(0.125, noiseVec), perlinnoise_Stage1_c0_c0(0.375, noiseVec), perlinnoise_Stage1_c0_c0(0.625, noiseVec), perlinnoise_Stage1_c0_c0(0.875, noiseVec)) * ratio;
+        noiseVec *= vec2(2.0);
+        ratio *= 0.5;
+    }
+    _output = _output * vec4(0.5) + vec4(0.5);
+    _output = clamp(_output, 0.0, 1.0);
+    _output = vec4(_output.xyz * _output.www, _output.w);
+    return _output;
+}
+vec4 SweepGradientLayout_Stage2_c1_c0_c0_c0(vec4 _input) {
+    vec4 _output;
+    float angle;
+    {
+        angle = atan(-vTransformedCoords_1_Stage0.y, -vTransformedCoords_1_Stage0.x);
+    }
+    float t = ((angle * 0.15915493667125702 + 0.5) + ubias_Stage2_c1_c0_c0_c0) * uscale_Stage2_c1_c0_c0_c0;
+    _output = vec4(t, 1.0, 0.0, 0.0);
+    return _output;
+}
+vec4 DualIntervalGradientColorizer_Stage2_c1_c0_c1_c0(vec4 _input) {
+    vec4 _output;
+    float t = _input.x;
+    vec4 scale, bias;
+    if (t < uthreshold_Stage2_c1_c0_c1_c0) {
+        scale = uscale01_Stage2_c1_c0_c1_c0;
+        bias = ubias01_Stage2_c1_c0_c1_c0;
+    } else {
+        scale = uscale23_Stage2_c1_c0_c1_c0;
+        bias = ubias23_Stage2_c1_c0_c1_c0;
+    }
+    _output = t * scale + bias;
+    return _output;
+}
+vec4 ClampedGradientEffect_Stage2_c1_c0(vec4 _input) {
+    vec4 _output;
+    vec4 t = SweepGradientLayout_Stage2_c1_c0_c0_c0(vec4(1.0));
+    if (t.x < 0.0) {
+        _output = uleftBorderColor_Stage2_c1_c0;
+    } else if (t.x > 1.0) {
+        _output = urightBorderColor_Stage2_c1_c0;
+    } else {
+        _output = DualIntervalGradientColorizer_Stage2_c1_c0_c1_c0(t);
+    }
+    {
+        _output.xyz *= _output.w;
+    }
+    return _output;
+}
+vec4 blend_src_in(vec4 src, vec4 dst) {
+    return src * dst.w;
+}
+vec4 blend_dst_in(vec4 src, vec4 dst) {
+    return blend_src_in(dst, src);
+}
+void main() {
+    vec4 outputColor_Stage0;
+    vec4 outputCoverage_Stage0;
+    {
+        outputColor_Stage0 = vcolor_Stage0;
+        float alpha = 1.0;
+        alpha = vinCoverage_Stage0;
+        outputCoverage_Stage0 = vec4(alpha);
+    }
+    vec4 output_Stage1;
+    {
+        output_Stage1 = blend_dst_in(outputColor_Stage0, PerlinNoise_Stage1_c0_c0(vec4(1.0)));
+    }
+    vec4 output_Stage2;
+    {
+        output_Stage2 = blend_dst_in(outputCoverage_Stage0, ClampedGradientEffect_Stage2_c1_c0(vec4(1.0)));
+    }
+    {
+        sk_FragColor = (vec4(1.0) - output_Stage1) * output_Stage2;
+    }
+}
+
+[vertex shader]
+#version 140
+
+uniform vec4 sk_RTAdjust;
+uniform mat3 uCoordTransformMatrix_0_Stage0;
+uniform mat3 uCoordTransformMatrix_1_Stage0;
+in vec2 inPosition;
+in vec4 inColor;
+in float inCoverage;
+noperspective out vec4 vcolor_Stage0;
+noperspective out vec2 vTransformedCoords_0_Stage0;
+noperspective out vec2 vTransformedCoords_1_Stage0;
+noperspective out float vinCoverage_Stage0;
+void main() {
+    vec4 color = inColor;
+    vcolor_Stage0 = color;
+    vec2 pos2 = inPosition;
+    vTransformedCoords_0_Stage0 = (uCoordTransformMatrix_0_Stage0 * vec3(inPosition, 1.0)).xy;
+    vTransformedCoords_1_Stage0 = (uCoordTransformMatrix_1_Stage0 * vec3(inPosition, 1.0)).xy;
+    vinCoverage_Stage0 = inCoverage;
+    gl_Position = vec4(pos2.x, pos2.y, 0.0, 1.0);
+    gl_Position = vec4(gl_Position.xy * sk_RTAdjust.xz + gl_Position.ww * sk_RTAdjust.yw, 0.0, gl_Position.w);
+}
+