Blend functions as SkSL built ins.
GPU-only for right now.
Use in GrGLSLBlend::AppendMode.
Remove unused GrGLSLBlend::AppendRegionOp.
Change-Id: I23affe255a1adafa55f3a07ca6291dc84e18e213
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/254678
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/glsl/GrGLSLBlend.cpp b/src/gpu/glsl/GrGLSLBlend.cpp
index 49810c3..a91bbb5 100644
--- a/src/gpu/glsl/GrGLSLBlend.cpp
+++ b/src/gpu/glsl/GrGLSLBlend.cpp
@@ -9,501 +9,42 @@
#include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h"
#include "src/gpu/glsl/GrGLSLProgramBuilder.h"
-//////////////////////////////////////////////////////////////////////////////
-// Advanced (non-coeff) blend helpers
-//////////////////////////////////////////////////////////////////////////////
-
-static void hard_light(GrGLSLFragmentBuilder* fsBuilder,
- const char* final,
- const char* src,
- const char* dst) {
- static const char kComponents[] = { 'r', 'g', 'b' };
- for (size_t i = 0; i < SK_ARRAY_COUNT(kComponents); ++i) {
- char component = kComponents[i];
- fsBuilder->codeAppendf("if (2.0 * %s.%c <= %s.a) {", src, component, src);
- fsBuilder->codeAppendf("%s.%c = 2.0 * %s.%c * %s.%c;",
- final, component, src, component, dst, component);
- fsBuilder->codeAppend("} else {");
- fsBuilder->codeAppendf("%s.%c = %s.a * %s.a - 2.0 * (%s.a - %s.%c) * (%s.a - %s.%c);",
- final, component, src, dst, dst, dst, component, src, src,
- component);
- fsBuilder->codeAppend("}");
- }
- fsBuilder->codeAppendf("%s.rgb += %s.rgb * (1.0 - %s.a) + %s.rgb * (1.0 - %s.a);",
- final, src, dst, dst, src);
-}
-
-// Does one component of color-dodge
-static void color_dodge_component(GrGLSLFragmentBuilder* fsBuilder,
- const char* final,
- const char* src,
- const char* dst,
- const char component) {
- const char* divisorGuard = "";
- const GrShaderCaps* shaderCaps = fsBuilder->getProgramBuilder()->shaderCaps();
- if (shaderCaps->mustGuardDivisionEvenAfterExplicitZeroCheck()) {
- divisorGuard = "+ 0.00000001";
- }
-
- fsBuilder->codeAppendf("if (0.0 == %s.%c) {", dst, component);
- fsBuilder->codeAppendf("%s.%c = %s.%c * (1.0 - %s.a);",
- final, component, src, component, dst);
- fsBuilder->codeAppend("} else {");
- fsBuilder->codeAppendf("half d = %s.a - %s.%c;", src, src, component);
- fsBuilder->codeAppend("if (0.0 == d) {");
- fsBuilder->codeAppendf("%s.%c = %s.a * %s.a + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
- final, component, src, dst, src, component, dst, dst, component,
- src);
- fsBuilder->codeAppend("} else {");
- fsBuilder->codeAppendf("d = min(%s.a, %s.%c * %s.a / (d %s));",
- dst, dst, component, src, divisorGuard);
- fsBuilder->codeAppendf("%s.%c = d * %s.a + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
- final, component, src, src, component, dst, dst, component, src);
- fsBuilder->codeAppend("}");
- fsBuilder->codeAppend("}");
-}
-
-// Does one component of color-burn
-static void color_burn_component(GrGLSLFragmentBuilder* fsBuilder,
- const char* final,
- const char* src,
- const char* dst,
- const char component) {
- const char* divisorGuard = "";
- const GrShaderCaps* shaderCaps = fsBuilder->getProgramBuilder()->shaderCaps();
- if (shaderCaps->mustGuardDivisionEvenAfterExplicitZeroCheck()) {
- divisorGuard = "+ 0.00000001";
- }
-
- fsBuilder->codeAppendf("if (%s.a == %s.%c) {", dst, dst, component);
- fsBuilder->codeAppendf("%s.%c = %s.a * %s.a + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
- final, component, src, dst, src, component, dst, dst, component,
- src);
- fsBuilder->codeAppendf("} else if (0.0 == %s.%c) {", src, component);
- fsBuilder->codeAppendf("%s.%c = %s.%c * (1.0 - %s.a);",
- final, component, dst, component, src);
- fsBuilder->codeAppend("} else {");
- fsBuilder->codeAppendf("half d = max(0.0, %s.a - (%s.a - %s.%c) * %s.a / (%s.%c %s));",
- dst, dst, dst, component, src, src, component, divisorGuard);
- fsBuilder->codeAppendf("%s.%c = %s.a * d + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
- final, component, src, src, component, dst, dst, component, src);
- fsBuilder->codeAppend("}");
-}
-
-// Does one component of soft-light. Caller should have already checked that dst alpha > 0.
-static void soft_light_component_pos_dst_alpha(GrGLSLFragmentBuilder* fsBuilder,
- const char* final,
- const char* src,
- const char* dst,
- const char component) {
- const char* divisorGuard = "";
- const GrShaderCaps* shaderCaps = fsBuilder->getProgramBuilder()->shaderCaps();
- if (shaderCaps->mustGuardDivisionEvenAfterExplicitZeroCheck()) {
- divisorGuard = "+ 0.00000001";
- }
-
- // if (2S < Sa)
- fsBuilder->codeAppendf("if (2.0 * %s.%c <= %s.a) {", src, component, src);
- // (D^2 (Sa-2 S))/Da+(1-Da) S+D (-Sa+2 S+1)
- fsBuilder->codeAppendf("%s.%c = (%s.%c*%s.%c*(%s.a - 2.0*%s.%c)) / (%s.a %s) +"
- "(1.0 - %s.a) * %s.%c + %s.%c*(-%s.a + 2.0*%s.%c + 1.0);",
- final, component, dst, component, dst, component, src, src,
- component, dst, divisorGuard, dst, src, component, dst, component, src,
- src, component);
- // else if (4D < Da)
- fsBuilder->codeAppendf("} else if (4.0 * %s.%c <= %s.a) {",
- dst, component, dst);
- fsBuilder->codeAppendf("half DSqd = %s.%c * %s.%c;",
- dst, component, dst, component);
- fsBuilder->codeAppendf("half DCub = DSqd * %s.%c;", dst, component);
- fsBuilder->codeAppendf("half DaSqd = %s.a * %s.a;", dst, dst);
- fsBuilder->codeAppendf("half DaCub = DaSqd * %s.a;", dst);
- // (Da^3 (-S)+Da^2 (S-D (3 Sa-6 S-1))+12 Da D^2 (Sa-2 S)-16 D^3 (Sa-2 S))/Da^2
- fsBuilder->codeAppendf("%s.%c ="
- "(DaSqd*(%s.%c - %s.%c * (3.0*%s.a - 6.0*%s.%c - 1.0)) +"
- " 12.0*%s.a*DSqd*(%s.a - 2.0*%s.%c) - 16.0*DCub * (%s.a - 2.0*%s.%c) -"
- " DaCub*%s.%c) / (DaSqd %s);",
- final, component, src, component, dst, component,
- src, src, component, dst, src, src, component, src, src,
- component, src, component, divisorGuard);
- fsBuilder->codeAppendf("} else {");
- // -sqrt(Da * D) (Sa-2 S)-Da S+D (Sa-2 S+1)+S
- fsBuilder->codeAppendf("%s.%c = %s.%c*(%s.a - 2.0*%s.%c + 1.0) + %s.%c -"
- " sqrt(%s.a*%s.%c)*(%s.a - 2.0*%s.%c) - %s.a*%s.%c;",
- final, component, dst, component, src, src, component, src, component,
- dst, dst, component, src, src, component, dst, src, component);
- fsBuilder->codeAppendf("}");
-}
-
-// Adds a function that takes two colors and an alpha as input. It produces a color with the
-// hue and saturation of the first color, the luminosity of the second color, and the input
-// alpha. It has this signature:
-// float3 set_luminance(float3 hueSatColor, float alpha, float3 lumColor).
-static void add_lum_function(GrGLSLFragmentBuilder* fsBuilder, SkString* setLumFunction) {
- // Emit a helper that gets the luminance of a color.
- SkString getFunction;
- GrShaderVar getLumArgs[] = {
- GrShaderVar("color", kHalf3_GrSLType),
- };
- SkString getLumBody("return dot(half3(0.3, 0.59, 0.11), color);");
- fsBuilder->emitFunction(kHalf_GrSLType,
- "luminance",
- SK_ARRAY_COUNT(getLumArgs), getLumArgs,
- getLumBody.c_str(),
- &getFunction);
-
- // Emit the set luminance function.
- GrShaderVar setLumArgs[] = {
- GrShaderVar("hueSat", kHalf3_GrSLType),
- GrShaderVar("alpha", kHalf_GrSLType),
- GrShaderVar("lumColor", kHalf3_GrSLType),
- };
- SkString setLumBody;
- setLumBody.printf("half outLum = %s(lumColor);", getFunction.c_str());
- setLumBody.appendf("half3 outColor = outLum - %s(hueSat) + hueSat;", getFunction.c_str());
- setLumBody.append("half minComp = min(min(outColor.r, outColor.g), outColor.b);"
- "half maxComp = max(max(outColor.r, outColor.g), outColor.b);"
- "if (minComp < 0.0 && outLum != minComp) {"
- "outColor = outLum + ((outColor - half3(outLum, outLum, outLum)) * outLum) /"
- "(outLum - minComp);"
- "}"
- "if (maxComp > alpha && maxComp != outLum) {"
- "outColor = outLum +"
- "((outColor - half3(outLum, outLum, outLum)) * (alpha - outLum)) /"
- "(maxComp - outLum);"
- "}"
- "return outColor;");
- fsBuilder->emitFunction(kHalf3_GrSLType,
- "set_luminance",
- SK_ARRAY_COUNT(setLumArgs), setLumArgs,
- setLumBody.c_str(),
- setLumFunction);
-}
-
-// Adds a function that creates a color with the hue and luminosity of one input color and
-// the saturation of another color. It will have this signature:
-// float set_saturation(float3 hueLumColor, float3 satColor)
-static void add_sat_function(GrGLSLFragmentBuilder* fsBuilder, SkString* setSatFunction) {
- // Emit a helper that gets the saturation of a color
- SkString getFunction;
- GrShaderVar getSatArgs[] = { GrShaderVar("color", kHalf3_GrSLType) };
- SkString getSatBody;
- getSatBody.printf("return max(max(color.r, color.g), color.b) - "
- "min(min(color.r, color.g), color.b);");
- fsBuilder->emitFunction(kHalf_GrSLType,
- "saturation",
- SK_ARRAY_COUNT(getSatArgs), getSatArgs,
- getSatBody.c_str(),
- &getFunction);
-
- // Emit a helper that sets the saturation given sorted input channels. This used
- // to use inout params for min, mid, and max components but that seems to cause
- // problems on PowerVR drivers. So instead it returns a float3 where r, g ,b are the
- // adjusted min, mid, and max inputs, respectively.
- SkString helperFunction;
- GrShaderVar helperArgs[] = {
- GrShaderVar("minComp", kHalf_GrSLType),
- GrShaderVar("midComp", kHalf_GrSLType),
- GrShaderVar("maxComp", kHalf_GrSLType),
- GrShaderVar("sat", kHalf_GrSLType),
- };
- static const char kHelperBody[] = "if (minComp < maxComp) {"
- "half3 result;"
- "result.r = 0.0;"
- "result.g = sat * (midComp - minComp) / (maxComp - minComp);"
- "result.b = sat;"
- "return result;"
- "} else {"
- "return half3(0, 0, 0);"
- "}";
- fsBuilder->emitFunction(kHalf3_GrSLType,
- "set_saturation_helper",
- SK_ARRAY_COUNT(helperArgs), helperArgs,
- kHelperBody,
- &helperFunction);
-
- GrShaderVar setSatArgs[] = {
- GrShaderVar("hueLumColor", kHalf3_GrSLType),
- GrShaderVar("satColor", kHalf3_GrSLType),
- };
- const char* helpFunc = helperFunction.c_str();
- SkString setSatBody;
- setSatBody.appendf("half sat = %s(satColor);"
- "if (hueLumColor.r <= hueLumColor.g) {"
- "if (hueLumColor.g <= hueLumColor.b) {"
- "hueLumColor.rgb = %s(hueLumColor.r, hueLumColor.g, hueLumColor.b, sat);"
- "} else if (hueLumColor.r <= hueLumColor.b) {"
- "hueLumColor.rbg = %s(hueLumColor.r, hueLumColor.b, hueLumColor.g, sat);"
- "} else {"
- "hueLumColor.brg = %s(hueLumColor.b, hueLumColor.r, hueLumColor.g, sat);"
- "}"
- "} else if (hueLumColor.r <= hueLumColor.b) {"
- "hueLumColor.grb = %s(hueLumColor.g, hueLumColor.r, hueLumColor.b, sat);"
- "} else if (hueLumColor.g <= hueLumColor.b) {"
- "hueLumColor.gbr = %s(hueLumColor.g, hueLumColor.b, hueLumColor.r, sat);"
- "} else {"
- "hueLumColor.bgr = %s(hueLumColor.b, hueLumColor.g, hueLumColor.r, sat);"
- "}"
- "return hueLumColor;",
- getFunction.c_str(), helpFunc, helpFunc, helpFunc, helpFunc,
- helpFunc, helpFunc);
- fsBuilder->emitFunction(kHalf3_GrSLType,
- "set_saturation",
- SK_ARRAY_COUNT(setSatArgs), setSatArgs,
- setSatBody.c_str(),
- setSatFunction);
-}
-
-static void emit_advanced_xfermode_code(GrGLSLFragmentBuilder* fsBuilder, const char* srcColor,
- const char* dstColor, const char* outputColor,
- SkBlendMode mode) {
- SkASSERT(srcColor);
- SkASSERT(dstColor);
- SkASSERT(outputColor);
- // These all perform src-over on the alpha channel.
- fsBuilder->codeAppendf("%s.a = %s.a + (1.0 - %s.a) * %s.a;",
- outputColor, srcColor, srcColor, dstColor);
-
- switch (mode) {
- case SkBlendMode::kOverlay:
- // Overlay is Hard-Light with the src and dst reversed
- hard_light(fsBuilder, outputColor, dstColor, srcColor);
- break;
- case SkBlendMode::kDarken:
- fsBuilder->codeAppendf("%s.rgb = min((1.0 - %s.a) * %s.rgb + %s.rgb, "
- "(1.0 - %s.a) * %s.rgb + %s.rgb);",
- outputColor,
- srcColor, dstColor, srcColor,
- dstColor, srcColor, dstColor);
- break;
- case SkBlendMode::kLighten:
- fsBuilder->codeAppendf("%s.rgb = max((1.0 - %s.a) * %s.rgb + %s.rgb, "
- "(1.0 - %s.a) * %s.rgb + %s.rgb);",
- outputColor,
- srcColor, dstColor, srcColor,
- dstColor, srcColor, dstColor);
- break;
- case SkBlendMode::kColorDodge:
- color_dodge_component(fsBuilder, outputColor, srcColor, dstColor, 'r');
- color_dodge_component(fsBuilder, outputColor, srcColor, dstColor, 'g');
- color_dodge_component(fsBuilder, outputColor, srcColor, dstColor, 'b');
- break;
- case SkBlendMode::kColorBurn:
- color_burn_component(fsBuilder, outputColor, srcColor, dstColor, 'r');
- color_burn_component(fsBuilder, outputColor, srcColor, dstColor, 'g');
- color_burn_component(fsBuilder, outputColor, srcColor, dstColor, 'b');
- break;
- case SkBlendMode::kHardLight:
- hard_light(fsBuilder, outputColor, srcColor, dstColor);
- break;
- case SkBlendMode::kSoftLight:
- fsBuilder->codeAppendf("if (0.0 == %s.a) {", dstColor);
- fsBuilder->codeAppendf("%s.rgba = %s;", outputColor, srcColor);
- fsBuilder->codeAppendf("} else {");
- soft_light_component_pos_dst_alpha(fsBuilder, outputColor, srcColor, dstColor, 'r');
- soft_light_component_pos_dst_alpha(fsBuilder, outputColor, srcColor, dstColor, 'g');
- soft_light_component_pos_dst_alpha(fsBuilder, outputColor, srcColor, dstColor, 'b');
- fsBuilder->codeAppendf("}");
- break;
- case SkBlendMode::kDifference:
- fsBuilder->codeAppendf("%s.rgb = %s.rgb + %s.rgb -"
- "2.0 * min(%s.rgb * %s.a, %s.rgb * %s.a);",
- outputColor, srcColor, dstColor, srcColor, dstColor,
- dstColor, srcColor);
- break;
- case SkBlendMode::kExclusion:
- fsBuilder->codeAppendf("%s.rgb = %s.rgb + %s.rgb - "
- "2.0 * %s.rgb * %s.rgb;",
- outputColor, dstColor, srcColor, dstColor, srcColor);
- break;
- case SkBlendMode::kMultiply:
- fsBuilder->codeAppendf("%s.rgb = (1.0 - %s.a) * %s.rgb + "
- "(1.0 - %s.a) * %s.rgb + "
- "%s.rgb * %s.rgb;",
- outputColor, srcColor, dstColor, dstColor, srcColor,
- srcColor, dstColor);
- break;
- case SkBlendMode::kHue: {
- // SetLum(SetSat(S * Da, Sat(D * Sa)), Sa*Da, D*Sa) + (1 - Sa) * D + (1 - Da) * S
- SkString setSat, setLum;
- add_sat_function(fsBuilder, &setSat);
- add_lum_function(fsBuilder, &setLum);
- fsBuilder->codeAppendf("half4 dstSrcAlpha = %s * %s.a;",
- dstColor, srcColor);
- fsBuilder->codeAppendf("%s.rgb = %s(%s(%s.rgb * %s.a, dstSrcAlpha.rgb),"
- "dstSrcAlpha.a, dstSrcAlpha.rgb);",
- outputColor, setLum.c_str(), setSat.c_str(), srcColor,
- dstColor);
- fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
- outputColor, srcColor, dstColor, dstColor, srcColor);
- break;
- }
- case SkBlendMode::kSaturation: {
- // SetLum(SetSat(D * Sa, Sat(S * Da)), Sa*Da, D*Sa)) + (1 - Sa) * D + (1 - Da) * S
- SkString setSat, setLum;
- add_sat_function(fsBuilder, &setSat);
- add_lum_function(fsBuilder, &setLum);
- fsBuilder->codeAppendf("half4 dstSrcAlpha = %s * %s.a;",
- dstColor, srcColor);
- fsBuilder->codeAppendf("%s.rgb = %s(%s(dstSrcAlpha.rgb, %s.rgb * %s.a),"
- "dstSrcAlpha.a, dstSrcAlpha.rgb);",
- outputColor, setLum.c_str(), setSat.c_str(), srcColor,
- dstColor);
- fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
- outputColor, srcColor, dstColor, dstColor, srcColor);
- break;
- }
- case SkBlendMode::kColor: {
- // SetLum(S * Da, Sa* Da, D * Sa) + (1 - Sa) * D + (1 - Da) * S
- SkString setLum;
- add_lum_function(fsBuilder, &setLum);
- fsBuilder->codeAppendf("half4 srcDstAlpha = %s * %s.a;",
- srcColor, dstColor);
- fsBuilder->codeAppendf("%s.rgb = %s(srcDstAlpha.rgb, srcDstAlpha.a, %s.rgb * %s.a);",
- outputColor, setLum.c_str(), dstColor, srcColor);
- fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
- outputColor, srcColor, dstColor, dstColor, srcColor);
- break;
- }
- case SkBlendMode::kLuminosity: {
- // SetLum(D * Sa, Sa* Da, S * Da) + (1 - Sa) * D + (1 - Da) * S
- SkString setLum;
- add_lum_function(fsBuilder, &setLum);
- fsBuilder->codeAppendf("half4 srcDstAlpha = %s * %s.a;",
- srcColor, dstColor);
- fsBuilder->codeAppendf("%s.rgb = %s(%s.rgb * %s.a, srcDstAlpha.a, srcDstAlpha.rgb);",
- outputColor, setLum.c_str(), dstColor, srcColor);
- fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
- outputColor, srcColor, dstColor, dstColor, srcColor);
- break;
- }
- default:
- SK_ABORT("Unknown Custom Xfer mode.");
- break;
- }
-}
-
-//////////////////////////////////////////////////////////////////////////////
-// Porter-Duff blend helper
-//////////////////////////////////////////////////////////////////////////////
-
-static bool append_porterduff_term(GrGLSLFragmentBuilder* fsBuilder, SkBlendModeCoeff coeff,
- const char* colorName, const char* srcColorName,
- const char* dstColorName, bool hasPrevious) {
- if (SkBlendModeCoeff::kZero == coeff) {
- return hasPrevious;
- } else {
- if (hasPrevious) {
- fsBuilder->codeAppend(" + ");
- }
- fsBuilder->codeAppendf("%s", colorName);
- switch (coeff) {
- case SkBlendModeCoeff::kOne:
- break;
- case SkBlendModeCoeff::kSC:
- fsBuilder->codeAppendf(" * %s", srcColorName);
- break;
- case SkBlendModeCoeff::kISC:
- fsBuilder->codeAppendf(" * (half4(1.0) - %s)", srcColorName);
- break;
- case SkBlendModeCoeff::kDC:
- fsBuilder->codeAppendf(" * %s", dstColorName);
- break;
- case SkBlendModeCoeff::kIDC:
- fsBuilder->codeAppendf(" * (half4(1.0) - %s)", dstColorName);
- break;
- case SkBlendModeCoeff::kSA:
- fsBuilder->codeAppendf(" * %s.a", srcColorName);
- break;
- case SkBlendModeCoeff::kISA:
- fsBuilder->codeAppendf(" * (1.0 - %s.a)", srcColorName);
- break;
- case SkBlendModeCoeff::kDA:
- fsBuilder->codeAppendf(" * %s.a", dstColorName);
- break;
- case SkBlendModeCoeff::kIDA:
- fsBuilder->codeAppendf(" * (1.0 - %s.a)", dstColorName);
- break;
- default:
- SK_ABORT("Unsupported Blend Coeff");
- }
- return true;
- }
-}
-
-//////////////////////////////////////////////////////////////////////////////
-
void GrGLSLBlend::AppendMode(GrGLSLFragmentBuilder* fsBuilder, const char* srcColor,
const char* dstColor, const char* outColor,
SkBlendMode mode) {
-
- SkBlendModeCoeff srcCoeff, dstCoeff;
- if (SkBlendMode_AsCoeff(mode, &srcCoeff, &dstCoeff)) {
- // The only coeff mode that can go out of range is plus.
- bool clamp = mode == SkBlendMode::kPlus;
-
- fsBuilder->codeAppendf("%s = ", outColor);
- if (clamp) {
- fsBuilder->codeAppend("clamp(");
- }
- // append src blend
- bool didAppend = append_porterduff_term(fsBuilder, srcCoeff, srcColor, srcColor, dstColor,
- false);
- // append dst blend
- if(!append_porterduff_term(fsBuilder, dstCoeff, dstColor, srcColor, dstColor, didAppend)) {
- fsBuilder->codeAppend("half4(0, 0, 0, 0)");
- }
- if (clamp) {
- fsBuilder->codeAppend(", 0, 1);");
- }
- fsBuilder->codeAppend(";");
- } else {
- emit_advanced_xfermode_code(fsBuilder, srcColor, dstColor, outColor, mode);
+ // When and if the SkSL compiler supports inlining we could replace this with
+ // out = blend(mode, src, dst) where mode is a literal.
+ const char* name;
+ switch (mode) {
+ case SkBlendMode::kClear: name = "clear"; break;
+ case SkBlendMode::kSrc: name = "src"; break;
+ case SkBlendMode::kDst: name = "dst"; break;
+ case SkBlendMode::kSrcOver: name = "src_over"; break;
+ case SkBlendMode::kDstOver: name = "dst_over"; break;
+ case SkBlendMode::kSrcIn: name = "src_in"; break;
+ case SkBlendMode::kDstIn: name = "dst_in"; break;
+ case SkBlendMode::kSrcOut: name = "src_out"; break;
+ case SkBlendMode::kDstOut: name = "dst_out"; break;
+ case SkBlendMode::kSrcATop: name = "src_atop"; break;
+ case SkBlendMode::kDstATop: name = "dst_atop"; break;
+ case SkBlendMode::kXor: name = "xor"; break;
+ case SkBlendMode::kPlus: name = "plus"; break;
+ case SkBlendMode::kModulate: name = "modulate"; break;
+ case SkBlendMode::kScreen: name = "screen"; break;
+ case SkBlendMode::kOverlay: name = "overlay"; break;
+ case SkBlendMode::kDarken: name = "darken"; break;
+ case SkBlendMode::kLighten: name = "lighten"; break;
+ case SkBlendMode::kColorDodge: name = "color_dodge"; break;
+ case SkBlendMode::kColorBurn: name = "color_burn"; break;
+ case SkBlendMode::kHardLight: name = "hard_light"; break;
+ case SkBlendMode::kSoftLight: name = "soft_light"; break;
+ case SkBlendMode::kDifference: name = "difference"; break;
+ case SkBlendMode::kExclusion: name = "exclusion"; break;
+ case SkBlendMode::kMultiply: name = "multiply"; break;
+ case SkBlendMode::kHue: name = "hue"; break;
+ case SkBlendMode::kSaturation: name = "saturation"; break;
+ case SkBlendMode::kColor: name = "color"; break;
+ case SkBlendMode::kLuminosity: name = "luminosity"; break;
}
-}
-
-void GrGLSLBlend::AppendRegionOp(GrGLSLFragmentBuilder* fsBuilder, const char* srcColor,
- const char* dstColor, const char* outColor,
- SkRegion::Op regionOp) {
- SkBlendModeCoeff srcCoeff, dstCoeff;
- switch (regionOp) {
- case SkRegion::kReplace_Op:
- srcCoeff = SkBlendModeCoeff::kOne;
- dstCoeff = SkBlendModeCoeff::kZero;
- break;
- case SkRegion::kIntersect_Op:
- srcCoeff = SkBlendModeCoeff::kDC;
- dstCoeff = SkBlendModeCoeff::kZero;
- break;
- case SkRegion::kUnion_Op:
- srcCoeff = SkBlendModeCoeff::kOne;
- dstCoeff = SkBlendModeCoeff::kISC;
- break;
- case SkRegion::kXOR_Op:
- srcCoeff = SkBlendModeCoeff::kIDC;
- dstCoeff = SkBlendModeCoeff::kISC;
- break;
- case SkRegion::kDifference_Op:
- srcCoeff = SkBlendModeCoeff::kZero;
- dstCoeff = SkBlendModeCoeff::kISC;
- break;
- case SkRegion::kReverseDifference_Op:
- srcCoeff = SkBlendModeCoeff::kIDC;
- dstCoeff = SkBlendModeCoeff::kZero;
- break;
- default:
- SK_ABORT("Unsupported Op");
- // We should never get here but to make compiler happy
- srcCoeff = SkBlendModeCoeff::kZero;
- dstCoeff = SkBlendModeCoeff::kZero;
- }
- fsBuilder->codeAppendf("%s = ", outColor);
- // append src blend
- bool didAppend = append_porterduff_term(fsBuilder, srcCoeff, srcColor, srcColor, dstColor,
- false);
- // append dst blend
- if(!append_porterduff_term(fsBuilder, dstCoeff, dstColor, srcColor, dstColor, didAppend)) {
- fsBuilder->codeAppend("half4(0, 0, 0, 0)");
- }
- fsBuilder->codeAppend(";");
+ fsBuilder->codeAppendf("%s = blend_%s(%s, %s);", outColor, name, srcColor, dstColor);
}
diff --git a/src/gpu/glsl/GrGLSLBlend.h b/src/gpu/glsl/GrGLSLBlend.h
index 69b821e..2851748 100644
--- a/src/gpu/glsl/GrGLSLBlend.h
+++ b/src/gpu/glsl/GrGLSLBlend.h
@@ -20,9 +20,6 @@
*/
void AppendMode(GrGLSLFragmentBuilder* fsBuilder, const char* srcColor,
const char* dstColor, const char* outColor, SkBlendMode mode);
-
- void AppendRegionOp(GrGLSLFragmentBuilder* fsBuilder, const char* srcColor,
- const char* dstColor, const char* outColor, SkRegion::Op regionOp);
};
#endif
diff --git a/src/sksl/SkSLCompiler.cpp b/src/sksl/SkSLCompiler.cpp
index 31492bd..bc42929 100644
--- a/src/sksl/SkSLCompiler.cpp
+++ b/src/sksl/SkSLCompiler.cpp
@@ -45,6 +45,10 @@
#include "sksl_gpu.inc"
;
+static const char* SKSL_BLEND_INCLUDE =
+#include "sksl_blend.inc"
+;
+
static const char* SKSL_INTERP_INCLUDE =
#include "sksl_interp.inc"
;
@@ -258,6 +262,9 @@
std::vector<std::unique_ptr<ProgramElement>> gpuIntrinsics;
this->processIncludeFile(Program::kFragment_Kind, SKSL_GPU_INCLUDE, strlen(SKSL_GPU_INCLUDE),
symbols, &gpuIntrinsics, &fGpuSymbolTable);
+ this->processIncludeFile(Program::kFragment_Kind, SKSL_BLEND_INCLUDE,
+ strlen(SKSL_BLEND_INCLUDE), std::move(fGpuSymbolTable), &gpuIntrinsics,
+ &fGpuSymbolTable);
grab_intrinsics(&gpuIntrinsics, &fGPUIntrinsics);
// need to hang on to the source so that FunctionDefinition.fSource pointers in this file
// remain valid
diff --git a/src/sksl/SkSLIRGenerator.cpp b/src/sksl/SkSLIRGenerator.cpp
index e2847e7..d61599c 100644
--- a/src/sksl/SkSLIRGenerator.cpp
+++ b/src/sksl/SkSLIRGenerator.cpp
@@ -132,6 +132,7 @@
CAP(mustEnableSpecificAdvBlendEqs);
CAP(mustDeclareFragmentShaderOutput);
CAP(mustDoOpBetweenFloorAndAbs);
+ CAP(mustGuardDivisionEvenAfterExplicitZeroCheck);
CAP(atan2ImplementedAsAtanYOverX);
CAP(canUseAnyFunctionInShader);
CAP(floatIs32Bits);
diff --git a/src/sksl/SkSLUtil.h b/src/sksl/SkSLUtil.h
index be9a74e..7cfe368 100644
--- a/src/sksl/SkSLUtil.h
+++ b/src/sksl/SkSLUtil.h
@@ -108,6 +108,10 @@
return false;
}
+ bool mustGuardDivisionEvenAfterExplicitZeroCheck() const {
+ return false;
+ }
+
bool mustEnableAdvBlendEqs() const {
return false;
}
diff --git a/src/sksl/sksl_blend.inc b/src/sksl/sksl_blend.inc
new file mode 100644
index 0000000..755834b
--- /dev/null
+++ b/src/sksl/sksl_blend.inc
@@ -0,0 +1,294 @@
+R"SKSL(
+// Definitions of functions implementing all of the SkBlendMode blends.
+
+half4 blend_clear(half4 src, half4 dst) { return half4(0); }
+
+half4 blend_src(half4 src, half4 dst) { return src; }
+
+half4 blend_dst(half4 src, half4 dst) { return dst; }
+
+half4 blend_src_over(half4 src, half4 dst) { return src + (1 - src.a)*dst; }
+
+half4 blend_dst_over(half4 src, half4 dst) { return (1 - dst.a)*src + dst; }
+
+half4 blend_src_in(half4 src, half4 dst) { return src*dst.a; }
+
+half4 blend_dst_in(half4 src, half4 dst) { return src.a*dst; }
+
+half4 blend_src_out(half4 src, half4 dst) { return (1 - dst.a)*src; }
+
+half4 blend_dst_out(half4 src, half4 dst) { return (1 - src.a)*dst; }
+
+half4 blend_src_atop(half4 src, half4 dst) { return dst.a*src + (1 - src.a)*dst; }
+
+half4 blend_dst_atop(half4 src, half4 dst) { return (1 - dst.a) * src + src.a*dst; }
+
+half4 blend_xor(half4 src, half4 dst) { return (1 - dst.a)*src + (1 - src.a)*dst; }
+
+half4 blend_plus(half4 src, half4 dst) { return min(src + dst, 1); }
+
+half4 blend_modulate(half4 src, half4 dst) { return src*dst; }
+
+half4 blend_screen(half4 src, half4 dst) { return src + (1 - src)*dst; }
+
+half _blend_overlay_component(half sc, half sa, half dc, half da) {
+ if (2*dc <= da) {
+ return 2*sc*dc;
+ }
+ return sa*da - 2*(da - dc)*(sa - sc);
+}
+
+half4 blend_overlay(half4 src, half4 dst) {
+ half4 result = half4(_blend_overlay_component(src.r, src.a, dst.r, dst.a),
+ _blend_overlay_component(src.g, src.a, dst.g, dst.a),
+ _blend_overlay_component(src.b, src.a, dst.b, dst.a),
+ src.a + (1 - src.a)*dst.a);
+ result.rgb += dst.rgb*(1 - src.a) + src.rgb*(1 - dst.a);
+ return result;
+}
+
+half4 blend_darken(half4 src, half4 dst) {
+ half4 result = blend_src_over(src, dst);
+ result.rgb = min(result.rgb, (1 - dst.a)*src.rgb + dst.rgb);
+ return result;
+}
+
+half4 blend_lighten(half4 src, half4 dst) {
+ half4 result = blend_src_over(src, dst);
+ result.rgb = max(result.rgb, (1 - dst.a)*src.rgb + dst.rgb);
+ return result;
+}
+
+half _guarded_divide(half n, half d) {
+ @if (sk_Caps.mustGuardDivisionEvenAfterExplicitZeroCheck) {
+ return n/(d + 0.00000001);
+ }
+ return n/d;
+}
+
+half _color_dodge_component(half sc, half sa, half dc, half da) {
+ if (dc == 0) {
+ return sc*(1 - da);
+ } else {
+ half d = sa - sc;
+ if (d == 0) {
+ return sa*da + sc*(1 - da) + dc*(1 - sa);
+ }
+ d = min(da, _guarded_divide(dc*sa, d));
+ return d*sa + sc*(1 - da) + dc*(1 - sa);
+ }
+}
+
+half4 blend_color_dodge(half4 src, half4 dst) {
+ return half4(_color_dodge_component(src.r, src.a, dst.r, dst.a),
+ _color_dodge_component(src.g, src.a, dst.g, dst.a),
+ _color_dodge_component(src.b, src.a, dst.b, dst.a),
+ src.a + (1 - src.a)*dst.a);
+}
+
+half _color_burn_component(half sc, half sa, half dc, half da) {
+ if (da == dc) {
+ return sa*da + sc*(1 - da) + dc*(1 - sa);
+ } else if (sc == 0) {
+ return dc*(1 - sa);
+ }
+ half d = max(0, da - _guarded_divide((da - dc)*sa, sc));
+ return d*sa + sc*(1 - da) + dc*(1 - sa);
+}
+
+half4 blend_color_burn(half4 src, half4 dst) {
+ return half4(_color_burn_component(src.r, src.a, dst.r, dst.a),
+ _color_burn_component(src.g, src.a, dst.g, dst.a),
+ _color_burn_component(src.b, src.a, dst.b, dst.a),
+ src.a + (1 - src.a)*dst.a);
+}
+
+half4 blend_hard_light(half4 src, half4 dst) { return blend_overlay(dst, src); }
+
+half _soft_light_component(half sc, half sa, half dc, half da) {
+ if (2*sc <= sa) {
+ return _guarded_divide(dc*dc*(sa - 2*sc), da) + (1 - da)*sc + dc*(-sa + 2*sc + 1);
+ } else if (4.0 * dc <= da) {
+ half DSqd = dc*dc;
+ half DCub = DSqd*dc;
+ half DaSqd = da*da;
+ half DaCub = DaSqd*da;
+ return _guarded_divide(DaSqd*(sc - dc*(3*sa - 6*sc - 1)) + 12*da*DSqd*(sa - 2*sc)
+ - 16*DCub * (sa - 2*sc) - DaCub*sc, DaSqd);
+ }
+ return dc*(sa - 2*sc + 1) + sc - sqrt(da*dc)*(sa - 2*sc) - da*sc;
+}
+
+half4 blend_soft_light(half4 src, half4 dst) {
+ if (dst.a == 0) {
+ return src;
+ }
+ return half4(_soft_light_component(src.r, src.a, dst.r, dst.a),
+ _soft_light_component(src.g, src.a, dst.g, dst.a),
+ _soft_light_component(src.b, src.a, dst.b, dst.a),
+ src.a + (1 - src.a)*dst.a);
+}
+
+half4 blend_difference(half4 src, half4 dst) {
+ return half4(src.rgb + dst.rgb - 2*min(src.rgb*dst.a, dst.rgb*src.a),
+ src.a + (1 - src.a)*dst.a);
+}
+
+half4 blend_exclusion(half4 src, half4 dst) {
+ return half4(dst.rgb + src.rgb - 2*dst.rgb*src.rgb, src.a + (1 - src.a)*dst.a);
+}
+
+half4 blend_multiply(half4 src, half4 dst) {
+ return half4((1 - src.a)*dst.rgb + (1 - dst.a)*src.rgb + src.rgb*dst.rgb,
+ src.a + (1 - src.a)*dst.a);
+}
+
+half _blend_color_luminance(half3 color) { return dot(half3(0.3, 0.59, 0.11), color); }
+
+half3 _blend_set_color_luminance(half3 hueSatColor, half alpha, half3 lumColor) {
+ half lum = _blend_color_luminance(lumColor);
+ half3 result = lum - _blend_color_luminance(hueSatColor) + hueSatColor;
+ half minComp = min(min(result.r, result.g), result.b);
+ half maxComp = max(max(result.r, result.g), result.b);
+ if (minComp < 0 && lum != minComp) {
+ result = lum + (result - lum) * lum/(lum - minComp);
+ }
+ if (maxComp > alpha && maxComp != lum) {
+ return lum + ((result - lum) * (alpha - lum))/(maxComp - lum);
+ }
+ return result;
+}
+
+half _blend_color_saturation(half3 color) {
+ return max(max(color.r, color.g), color.b) - min(min(color.r, color.g), color.b);
+}
+
+half3 _blend_set_color_saturation_helper(half3 minMidMax, half sat) {
+ if (minMidMax.r < minMidMax.b) {
+ return half3(0, sat*(minMidMax.g - minMidMax.r)/(minMidMax.b - minMidMax.r), sat);
+ }
+ return half3(0);
+}
+
+half3 _blend_set_color_saturation(half3 hueLumColor, half3 satColor) {
+ half sat = _blend_color_saturation(satColor);
+ if (hueLumColor.r <= hueLumColor.g) {
+ if (hueLumColor.g <= hueLumColor.b) {
+ hueLumColor.rgb = _blend_set_color_saturation_helper(hueLumColor.rgb, sat);
+ } else if (hueLumColor.r <= hueLumColor.b) {
+ hueLumColor.rbg = _blend_set_color_saturation_helper(hueLumColor.rbg, sat);
+ } else {
+ hueLumColor.brg = _blend_set_color_saturation_helper(hueLumColor.brg, sat);
+ }
+ } else if (hueLumColor.r <= hueLumColor.b) {
+ hueLumColor.grb = _blend_set_color_saturation_helper(hueLumColor.grb, sat);
+ } else if (hueLumColor.g <= hueLumColor.b) {
+ hueLumColor.gbr = _blend_set_color_saturation_helper(hueLumColor.gbr, sat);
+ } else {
+ hueLumColor.bgr = _blend_set_color_saturation_helper(hueLumColor.bgr, sat);
+ }
+ return hueLumColor;
+}
+
+half4 blend_hue(half4 src, half4 dst) {
+ half alpha = dst.a*src.a;
+ half3 sda = src.rgb*dst.a;
+ half3 dsa = dst.rgb*src.a;
+ return half4(_blend_set_color_luminance(_blend_set_color_saturation(sda, dsa), alpha, dsa) +
+ dst.rgb - dsa + src.rgb - sda,
+ src.a + dst.a - alpha);
+}
+
+half4 blend_saturation(half4 src, half4 dst) {
+ half alpha = dst.a*src.a;
+ half3 sda = src.rgb*dst.a;
+ half3 dsa = dst.rgb*src.a;
+ return half4(_blend_set_color_luminance(_blend_set_color_saturation(dsa, sda), alpha, dsa) +
+ dst.rgb - dsa + src.rgb - sda,
+ src.a + dst.a - alpha);
+}
+
+half4 blend_color(half4 src, half4 dst) {
+ half alpha = dst.a*src.a;
+ half3 sda = src.rgb*dst.a;
+ half3 dsa = dst.rgb*src.a;
+ return half4(_blend_set_color_luminance(sda, alpha, dsa) + dst.rgb - dsa + src.rgb - sda,
+ src.a + dst.a - alpha);
+}
+
+half4 blend_luminosity(half4 src, half4 dst) {
+ half alpha = dst.a*src.a;
+ half3 sda = src.rgb*dst.a;
+ half3 dsa = dst.rgb*src.a;
+ return half4(_blend_set_color_luminance(dsa, alpha, sda) + dst.rgb - dsa + src.rgb - sda,
+ src.a + dst.a - alpha);
+
+}
+
+enum class SkBlendMode {
+ kClear = 0,
+ kSrc = 1,
+ kDst = 2,
+ kSrcOver = 3,
+ kDstOver = 4,
+ kSrcIn = 5,
+ kDstIn = 6,
+ kSrcOut = 7,
+ kDstOut = 8,
+ kSrcATop = 9,
+ kDstATop = 10,
+ kXor = 11,
+ kPlus = 12,
+ kModulate = 13,
+ kScreen = 14,
+ kOverlay = 15,
+ kDarken = 16,
+ kLighten = 17,
+ kColorDodge = 18,
+ kColorBurn = 19,
+ kHardLight = 20,
+ kSoftLight = 21,
+ kDifference = 22,
+ kExclusion = 23,
+ kMultiply = 24,
+ kHue = 25,
+ kSaturation = 26,
+ kColor = 27,
+ kLuminosity = 28
+};
+
+half4 blend(SkBlendMode mode, half4 src, half4 dst) {
+ switch (mode) {
+ case SkBlendMode::kClear: return blend_clear(src, dst);
+ case SkBlendMode::kSrc: return blend_src(src, dst);
+ case SkBlendMode::kDst: return blend_dst(src, dst);
+ case SkBlendMode::kSrcOver: return blend_src_over(src, dst);
+ case SkBlendMode::kDstOver: return blend_dst_over(src, dst);
+ case SkBlendMode::kSrcIn: return blend_src_in(src, dst);
+ case SkBlendMode::kDstIn: return blend_dst_in(src, dst);
+ case SkBlendMode::kSrcOut: return blend_src_out(src, dst);
+ case SkBlendMode::kDstOut: return blend_dst_out(src, dst);
+ case SkBlendMode::kSrcATop: return blend_src_atop(src, dst);
+ case SkBlendMode::kDstATop: return blend_dst_atop(src, dst);
+ case SkBlendMode::kXor: return blend_xor(src, dst);
+ case SkBlendMode::kPlus: return blend_plus(src, dst);
+ case SkBlendMode::kModulate: return blend_modulate(src, dst);
+ case SkBlendMode::kScreen: return blend_screen(src, dst);
+ case SkBlendMode::kOverlay: return blend_overlay(src, dst);
+ case SkBlendMode::kDarken: return blend_darken(src, dst);
+ case SkBlendMode::kLighten: return blend_lighten(src, dst);
+ case SkBlendMode::kColorDodge: return blend_color_dodge(src, dst);
+ case SkBlendMode::kColorBurn: return blend_color_burn(src, dst);
+ case SkBlendMode::kHardLight: return blend_hard_light(src, dst);
+ case SkBlendMode::kSoftLight: return blend_soft_light(src, dst);
+ case SkBlendMode::kDifference: return blend_difference(src, dst);
+ case SkBlendMode::kExclusion: return blend_exclusion(src, dst);
+ case SkBlendMode::kMultiply: return blend_multiply(src, dst);
+ case SkBlendMode::kHue: return blend_hue(src, dst);
+ case SkBlendMode::kSaturation: return blend_saturation(src, dst);
+ case SkBlendMode::kColor: return blend_color(src, dst);
+ case SkBlendMode::kLuminosity: return blend_luminosity(src, dst);
+ }
+ return half4(0); // Avoids "'blend' can exit without returning a value."
+}
+)SKSL"
diff --git a/src/sksl/sksl_gpu.inc b/src/sksl/sksl_gpu.inc
index c027c2c..14e8bae 100644
--- a/src/sksl/sksl_gpu.inc
+++ b/src/sksl/sksl_gpu.inc
@@ -1,4 +1,4 @@
-STRINGIFY(
+R"SKSL(
// defines built-in functions supported by SkSL when running on a GPU
@@ -295,5 +295,4 @@
float2 interpolateAtOffset(float2 interpolant, float2 offset);
float3 interpolateAtOffset(float3 interpolant, float2 offset);
float4 interpolateAtOffset(float4 interpolant, float2 offset);
-
-)
+)SKSL"
diff --git a/tests/ProcessorTest.cpp b/tests/ProcessorTest.cpp
index 978f7ef..aa518f9 100644
--- a/tests/ProcessorTest.cpp
+++ b/tests/ProcessorTest.cpp
@@ -343,10 +343,10 @@
bool fuzzy_color_equals(const SkPMColor4f& c1, const SkPMColor4f& c2) {
// With the loss of precision of rendering into 32-bit color, then estimating the FP's output
- // from that, it is not uncommon for a valid output to differ from estimate by up to 0.01
+ // from that, it is not uncommon for a valid output to differ from estimate by up to 0.03
// (really 1/128 ~ .0078, but frequently floating point issues make that tolerance a little
// too unforgiving).
- static constexpr SkScalar kTolerance = 0.01f;
+ static constexpr SkScalar kTolerance = 0.03f;
for (int i = 0; i < 4; i++) {
if (!SkScalarNearlyEqual(c1[i], c2[i], kTolerance)) {
return false;