blob: b8666eaca70e899094bd32d1bd5bffae58f08f76 [file] [log] [blame]
/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "src/core/SkDistanceFieldGen.h"
#include "src/gpu/KeyBuilder.h"
#include "src/gpu/ganesh/GrCaps.h"
#include "src/gpu/ganesh/GrShaderCaps.h"
#include "src/gpu/ganesh/GrTexture.h"
#include "src/gpu/ganesh/effects/GrAtlasedShaderHelpers.h"
#include "src/gpu/ganesh/effects/GrDistanceFieldGeoProc.h"
#include "src/gpu/ganesh/glsl/GrGLSLFragmentShaderBuilder.h"
#include "src/gpu/ganesh/glsl/GrGLSLProgramDataManager.h"
#include "src/gpu/ganesh/glsl/GrGLSLUniformHandler.h"
#include "src/gpu/ganesh/glsl/GrGLSLVarying.h"
#include "src/gpu/ganesh/glsl/GrGLSLVertexGeoBuilder.h"
#if !defined(SK_DISABLE_SDF_TEXT)
// Assuming a radius of a little less than the diagonal of the fragment
#define SK_DistanceFieldAAFactor "0.65"
class GrDistanceFieldA8TextGeoProc::Impl : public ProgramImpl {
public:
void setData(const GrGLSLProgramDataManager& pdman,
const GrShaderCaps& shaderCaps,
const GrGeometryProcessor& geomProc) override {
const GrDistanceFieldA8TextGeoProc& dfa8gp = geomProc.cast<GrDistanceFieldA8TextGeoProc>();
#ifdef SK_GAMMA_APPLY_TO_A8
float distanceAdjust = dfa8gp.fDistanceAdjust;
if (distanceAdjust != fDistanceAdjust) {
fDistanceAdjust = distanceAdjust;
pdman.set1f(fDistanceAdjustUni, distanceAdjust);
}
#endif
const SkISize& atlasDimensions = dfa8gp.fAtlasDimensions;
SkASSERT(SkIsPow2(atlasDimensions.fWidth) && SkIsPow2(atlasDimensions.fHeight));
if (fAtlasDimensions != atlasDimensions) {
pdman.set2f(fAtlasDimensionsInvUniform,
1.0f / atlasDimensions.fWidth,
1.0f / atlasDimensions.fHeight);
fAtlasDimensions = atlasDimensions;
}
SetTransform(pdman, shaderCaps, fLocalMatrixUniform, dfa8gp.fLocalMatrix, &fLocalMatrix);
}
private:
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldA8TextGeoProc& dfTexEffect =
args.fGeomProc.cast<GrDistanceFieldA8TextGeoProc>();
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
const char* atlasDimensionsInvName;
fAtlasDimensionsInvUniform = uniformHandler->addUniform(nullptr,
kVertex_GrShaderFlag,
SkSLType::kFloat2,
"AtlasDimensionsInv",
&atlasDimensionsInvName);
#ifdef SK_GAMMA_APPLY_TO_A8
// adjust based on gamma
const char* distanceAdjustUniName = nullptr;
// width, height, 1/(3*width)
fDistanceAdjustUni = uniformHandler->addUniform(nullptr, kFragment_GrShaderFlag,
SkSLType::kHalf, "DistanceAdjust",
&distanceAdjustUniName);
#endif
// Setup pass through color
fragBuilder->codeAppendf("half4 %s;\n", args.fOutputColor);
varyingHandler->addPassThroughAttribute(dfTexEffect.fInColor.asShaderVar(),
args.fOutputColor);
// Setup position
gpArgs->fPositionVar = dfTexEffect.fInPosition.asShaderVar();
WriteLocalCoord(vertBuilder,
uniformHandler,
*args.fShaderCaps,
gpArgs,
gpArgs->fPositionVar,
dfTexEffect.fLocalMatrix,
&fLocalMatrixUniform);
// add varyings
GrGLSLVarying uv, texIdx, st;
append_index_uv_varyings(args,
dfTexEffect.numTextureSamplers(),
dfTexEffect.fInTextureCoords.name(),
atlasDimensionsInvName,
&uv,
&texIdx,
&st);
bool isUniformScale = (dfTexEffect.fFlags & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfTexEffect.fFlags & kSimilarity_DistanceFieldEffectFlag );
bool isGammaCorrect = SkToBool(dfTexEffect.fFlags & kGammaCorrect_DistanceFieldEffectFlag);
bool isAliased = SkToBool(dfTexEffect.fFlags & kAliased_DistanceFieldEffectFlag );
// Use highp to work around aliasing issues
fragBuilder->codeAppendf("float2 uv = %s;\n", uv.fsIn());
fragBuilder->codeAppend("half4 texColor;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv", "texColor");
fragBuilder->codeAppend("half distance = "
SK_DistanceFieldMultiplier "*(texColor.r - " SK_DistanceFieldThreshold ");");
#ifdef SK_GAMMA_APPLY_TO_A8
// adjust width based on gamma
fragBuilder->codeAppendf("distance -= %s;", distanceAdjustUniName);
#endif
fragBuilder->codeAppend("half afwidth;");
if (isUniformScale) {
// For uniform scale, we adjust for the effect of the transformation on the distance
// by using the length of the gradient of the t coordinate in the y direction.
// We use st coordinates to ensure we're mapping 1:1 from texel space to pixel space.
// this gives us a smooth step across approximately one fragment
if (args.fShaderCaps->fAvoidDfDxForGradientsWhenPossible) {
fragBuilder->codeAppendf(
"afwidth = abs(" SK_DistanceFieldAAFactor "*half(dFdy(%s.y)));", st.fsIn());
} else {
fragBuilder->codeAppendf(
"afwidth = abs(" SK_DistanceFieldAAFactor "*half(dFdx(%s.x)));", st.fsIn());
}
} else if (isSimilarity) {
// For similarity transform, we adjust the effect of the transformation on the distance
// by using the length of the gradient of the texture coordinates. We use st coordinates
// to ensure we're mapping 1:1 from texel space to pixel space.
// We use the y gradient because there is a bug in the Mali 400 in the x direction.
// this gives us a smooth step across approximately one fragment
if (args.fShaderCaps->fAvoidDfDxForGradientsWhenPossible) {
fragBuilder->codeAppendf("half st_grad_len = length(half2(dFdy(%s)));", st.fsIn());
} else {
fragBuilder->codeAppendf("half st_grad_len = length(half2(dFdx(%s)));", st.fsIn());
}
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*st_grad_len);");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("half2 dist_grad = half2(float2(dFdx(distance), "
"dFdy(distance)));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("half dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = half2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*half(inversesqrt(dg_len2));");
fragBuilder->codeAppend("}");
fragBuilder->codeAppendf("half2 Jdx = half2(dFdx(%s));", st.fsIn());
fragBuilder->codeAppendf("half2 Jdy = half2(dFdy(%s));", st.fsIn());
fragBuilder->codeAppend("half2 grad = half2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
if (isAliased) {
fragBuilder->codeAppend("half val = distance > 0 ? 1.0 : 0.0;");
} else if (isGammaCorrect) {
// The smoothstep falloff compensates for the non-linear sRGB response curve. If we are
// doing gamma-correct rendering (to an sRGB or F16 buffer), then we actually want
// distance mapped linearly to coverage, so use a linear step:
fragBuilder->codeAppend(
"half val = saturate((distance + afwidth) / (2.0 * afwidth));");
} else {
fragBuilder->codeAppend("half val = smoothstep(-afwidth, afwidth, distance);");
}
fragBuilder->codeAppendf("half4 %s = half4(val);", args.fOutputCoverage);
}
private:
#ifdef SK_GAMMA_APPLY_TO_A8
float fDistanceAdjust = -1.f;
#endif
SkISize fAtlasDimensions = {-1, -1};
SkMatrix fLocalMatrix = SkMatrix::InvalidMatrix();
UniformHandle fDistanceAdjustUni;
UniformHandle fAtlasDimensionsInvUniform;
UniformHandle fLocalMatrixUniform;
using INHERITED = ProgramImpl;
};
///////////////////////////////////////////////////////////////////////////////
GrDistanceFieldA8TextGeoProc::GrDistanceFieldA8TextGeoProc(const GrShaderCaps& caps,
const GrSurfaceProxyView* views,
int numViews,
GrSamplerState params,
#ifdef SK_GAMMA_APPLY_TO_A8
float distanceAdjust,
#endif
uint32_t flags,
const SkMatrix& localMatrix)
: INHERITED(kGrDistanceFieldA8TextGeoProc_ClassID)
, fLocalMatrix(localMatrix)
, fFlags(flags & kNonLCD_DistanceFieldEffectMask)
#ifdef SK_GAMMA_APPLY_TO_A8
, fDistanceAdjust(distanceAdjust)
#endif
{
SkASSERT(numViews <= kMaxTextures);
SkASSERT(!(flags & ~kNonLCD_DistanceFieldEffectMask));
if (flags & kPerspective_DistanceFieldEffectFlag) {
fInPosition = {"inPosition", kFloat3_GrVertexAttribType, SkSLType::kFloat3};
} else {
fInPosition = {"inPosition", kFloat2_GrVertexAttribType, SkSLType::kFloat2};
}
fInColor = {"inColor", kUByte4_norm_GrVertexAttribType, SkSLType::kHalf4 };
fInTextureCoords = {"inTextureCoords", kUShort2_GrVertexAttribType,
caps.fIntegerSupport ? SkSLType::kUShort2 : SkSLType::kFloat2};
this->setVertexAttributesWithImplicitOffsets(&fInPosition, 3);
if (numViews) {
fAtlasDimensions = views[0].proxy()->dimensions();
}
for (int i = 0; i < numViews; ++i) {
const GrSurfaceProxy* proxy = views[i].proxy();
SkASSERT(proxy);
SkASSERT(proxy->dimensions() == fAtlasDimensions);
fTextureSamplers[i].reset(params, proxy->backendFormat(), views[i].swizzle());
}
this->setTextureSamplerCnt(numViews);
}
void GrDistanceFieldA8TextGeoProc::addNewViews(const GrSurfaceProxyView* views,
int numViews,
GrSamplerState params) {
SkASSERT(numViews <= kMaxTextures);
// Just to make sure we don't try to add too many proxies
numViews = std::min(numViews, kMaxTextures);
if (!fTextureSamplers[0].isInitialized()) {
fAtlasDimensions = views[0].proxy()->dimensions();
}
for (int i = 0; i < numViews; ++i) {
const GrSurfaceProxy* proxy = views[i].proxy();
SkASSERT(proxy);
SkASSERT(proxy->dimensions() == fAtlasDimensions);
if (!fTextureSamplers[i].isInitialized()) {
fTextureSamplers[i].reset(params, proxy->backendFormat(), views[i].swizzle());
}
}
this->setTextureSamplerCnt(numViews);
}
void GrDistanceFieldA8TextGeoProc::addToKey(const GrShaderCaps& caps,
skgpu::KeyBuilder* b) const {
uint32_t key = 0;
key |= fFlags;
key |= ProgramImpl::ComputeMatrixKey(caps, fLocalMatrix) << 16;
b->add32(key);
b->add32(this->numTextureSamplers());
}
std::unique_ptr<GrGeometryProcessor::ProgramImpl> GrDistanceFieldA8TextGeoProc::makeProgramImpl(
const GrShaderCaps&) const {
return std::make_unique<Impl>();
}
///////////////////////////////////////////////////////////////////////////////
GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldA8TextGeoProc)
#if GR_TEST_UTILS
GrGeometryProcessor* GrDistanceFieldA8TextGeoProc::TestCreate(GrProcessorTestData* d) {
auto [view, ct, at] = d->randomAlphaOnlyView();
GrSamplerState::WrapMode wrapModes[2];
GrTest::TestWrapModes(d->fRandom, wrapModes);
GrSamplerState samplerState(wrapModes, d->fRandom->nextBool()
? GrSamplerState::Filter::kLinear
: GrSamplerState::Filter::kNearest);
uint32_t flags = 0;
flags |= d->fRandom->nextBool() ? kSimilarity_DistanceFieldEffectFlag : 0;
if (flags & kSimilarity_DistanceFieldEffectFlag) {
flags |= d->fRandom->nextBool() ? kScaleOnly_DistanceFieldEffectFlag : 0;
}
SkMatrix localMatrix = GrTest::TestMatrix(d->fRandom);
#ifdef SK_GAMMA_APPLY_TO_A8
float lum = d->fRandom->nextF();
#endif
return GrDistanceFieldA8TextGeoProc::Make(d->allocator(), *d->caps()->shaderCaps(),
&view, 1,
samplerState,
#ifdef SK_GAMMA_APPLY_TO_A8
lum,
#endif
flags, localMatrix);
}
#endif
///////////////////////////////////////////////////////////////////////////////
class GrDistanceFieldPathGeoProc::Impl : public ProgramImpl {
public:
void setData(const GrGLSLProgramDataManager& pdman,
const GrShaderCaps& shaderCaps,
const GrGeometryProcessor& geomProc) override {
const GrDistanceFieldPathGeoProc& dfpgp = geomProc.cast<GrDistanceFieldPathGeoProc>();
// We always set the matrix uniform. It's used to transform from from device to local
// for the local coord variable.
SetTransform(pdman, shaderCaps, fLocalMatrixUniform, dfpgp.fLocalMatrix, &fLocalMatrix);
const SkISize& atlasDimensions = dfpgp.fAtlasDimensions;
SkASSERT(SkIsPow2(atlasDimensions.fWidth) && SkIsPow2(atlasDimensions.fHeight));
if (fAtlasDimensions != atlasDimensions) {
pdman.set2f(fAtlasDimensionsInvUniform,
1.0f / atlasDimensions.fWidth,
1.0f / atlasDimensions.fHeight);
fAtlasDimensions = atlasDimensions;
}
}
private:
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldPathGeoProc& dfPathEffect =
args.fGeomProc.cast<GrDistanceFieldPathGeoProc>();
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfPathEffect);
const char* atlasDimensionsInvName;
fAtlasDimensionsInvUniform = uniformHandler->addUniform(nullptr,
kVertex_GrShaderFlag,
SkSLType::kFloat2,
"AtlasDimensionsInv",
&atlasDimensionsInvName);
GrGLSLVarying uv, texIdx, st;
append_index_uv_varyings(args,
dfPathEffect.numTextureSamplers(),
dfPathEffect.fInTextureCoords.name(),
atlasDimensionsInvName,
&uv,
&texIdx,
&st);
// setup pass through color
fragBuilder->codeAppendf("half4 %s;", args.fOutputColor);
varyingHandler->addPassThroughAttribute(dfPathEffect.fInColor.asShaderVar(),
args.fOutputColor);
// Setup position (output position is pass through, local coords are transformed)
gpArgs->fPositionVar = dfPathEffect.fInPosition.asShaderVar();
WriteLocalCoord(vertBuilder,
uniformHandler,
*args.fShaderCaps,
gpArgs,
gpArgs->fPositionVar,
dfPathEffect.fLocalMatrix,
&fLocalMatrixUniform);
// Use highp to work around aliasing issues
fragBuilder->codeAppendf("float2 uv = %s;", uv.fsIn());
fragBuilder->codeAppend("half4 texColor;");
append_multitexture_lookup(args, dfPathEffect.numTextureSamplers(), texIdx, "uv",
"texColor");
fragBuilder->codeAppend("half distance = "
SK_DistanceFieldMultiplier "*(texColor.r - " SK_DistanceFieldThreshold ");");
fragBuilder->codeAppend("half afwidth;");
bool isUniformScale = (dfPathEffect.fFlags & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfPathEffect.fFlags & kSimilarity_DistanceFieldEffectFlag );
bool isGammaCorrect = SkToBool(dfPathEffect.fFlags & kGammaCorrect_DistanceFieldEffectFlag);
if (isUniformScale) {
// For uniform scale, we adjust for the effect of the transformation on the distance
// by using the length of the gradient of the t coordinate in the y direction.
// We use st coordinates to ensure we're mapping 1:1 from texel space to pixel space.
// this gives us a smooth step across approximately one fragment
if (args.fShaderCaps->fAvoidDfDxForGradientsWhenPossible) {
fragBuilder->codeAppendf(
"afwidth = abs(" SK_DistanceFieldAAFactor "*half(dFdy(%s.y)));", st.fsIn());
} else {
fragBuilder->codeAppendf(
"afwidth = abs(" SK_DistanceFieldAAFactor "*half(dFdx(%s.x)));", st.fsIn());
}
} else if (isSimilarity) {
// For similarity transform, we adjust the effect of the transformation on the distance
// by using the length of the gradient of the texture coordinates. We use st coordinates
// to ensure we're mapping 1:1 from texel space to pixel space.
// this gives us a smooth step across approximately one fragment
if (args.fShaderCaps->fAvoidDfDxForGradientsWhenPossible) {
fragBuilder->codeAppendf("half st_grad_len = half(length(dFdy(%s)));", st.fsIn());
} else {
fragBuilder->codeAppendf("half st_grad_len = half(length(dFdx(%s)));", st.fsIn());
}
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*st_grad_len);");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("half2 dist_grad = half2(dFdx(distance), "
"dFdy(distance));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("half dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = half2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*half(inversesqrt(dg_len2));");
fragBuilder->codeAppend("}");
fragBuilder->codeAppendf("half2 Jdx = half2(dFdx(%s));", st.fsIn());
fragBuilder->codeAppendf("half2 Jdy = half2(dFdy(%s));", st.fsIn());
fragBuilder->codeAppend("half2 grad = half2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
// The smoothstep falloff compensates for the non-linear sRGB response curve. If we are
// doing gamma-correct rendering (to an sRGB or F16 buffer), then we actually want distance
// mapped linearly to coverage, so use a linear step:
if (isGammaCorrect) {
fragBuilder->codeAppend(
"half val = saturate((distance + afwidth) / (2.0 * afwidth));");
} else {
fragBuilder->codeAppend("half val = smoothstep(-afwidth, afwidth, distance);");
}
fragBuilder->codeAppendf("half4 %s = half4(val);", args.fOutputCoverage);
}
SkMatrix fLocalMatrix;
UniformHandle fLocalMatrixUniform;
SkISize fAtlasDimensions;
UniformHandle fAtlasDimensionsInvUniform;
using INHERITED = ProgramImpl;
};
///////////////////////////////////////////////////////////////////////////////
GrDistanceFieldPathGeoProc::GrDistanceFieldPathGeoProc(const GrShaderCaps& caps,
const GrSurfaceProxyView* views,
int numViews,
GrSamplerState params,
const SkMatrix& localMatrix,
uint32_t flags)
: INHERITED(kGrDistanceFieldPathGeoProc_ClassID)
, fLocalMatrix(localMatrix)
, fFlags(flags & kPath_DistanceFieldEffectMask) {
SkASSERT(numViews <= kMaxTextures);
SkASSERT(!(flags & ~kPath_DistanceFieldEffectMask));
fInPosition = {"inPosition", kFloat3_GrVertexAttribType, SkSLType::kFloat3};
fInColor = MakeColorAttribute("inColor", SkToBool(flags & kWideColor_DistanceFieldEffectFlag));
fInTextureCoords = {"inTextureCoords", kUShort2_GrVertexAttribType,
caps.fIntegerSupport ? SkSLType::kUShort2 : SkSLType::kFloat2};
this->setVertexAttributesWithImplicitOffsets(&fInPosition, 3);
if (numViews) {
fAtlasDimensions = views[0].proxy()->dimensions();
}
for (int i = 0; i < numViews; ++i) {
const GrSurfaceProxy* proxy = views[i].proxy();
SkASSERT(proxy);
SkASSERT(proxy->dimensions() == fAtlasDimensions);
fTextureSamplers[i].reset(params, proxy->backendFormat(), views[i].swizzle());
}
this->setTextureSamplerCnt(numViews);
}
void GrDistanceFieldPathGeoProc::addNewViews(const GrSurfaceProxyView* views,
int numViews,
GrSamplerState params) {
SkASSERT(numViews <= kMaxTextures);
// Just to make sure we don't try to add too many proxies
numViews = std::min(numViews, kMaxTextures);
if (!fTextureSamplers[0].isInitialized()) {
fAtlasDimensions = views[0].proxy()->dimensions();
}
for (int i = 0; i < numViews; ++i) {
const GrSurfaceProxy* proxy = views[i].proxy();
SkASSERT(proxy);
SkASSERT(proxy->dimensions() == fAtlasDimensions);
if (!fTextureSamplers[i].isInitialized()) {
fTextureSamplers[i].reset(params, proxy->backendFormat(), views[i].swizzle());
}
}
this->setTextureSamplerCnt(numViews);
}
void GrDistanceFieldPathGeoProc::addToKey(const GrShaderCaps& caps,
skgpu::KeyBuilder* b) const {
uint32_t key = fFlags;
key |= ProgramImpl::ComputeMatrixKey(caps, fLocalMatrix) << 16;
key |= fLocalMatrix.hasPerspective() << (16 + ProgramImpl::kMatrixKeyBits);
b->add32(key);
b->add32(this->numTextureSamplers());
}
std::unique_ptr<GrGeometryProcessor::ProgramImpl> GrDistanceFieldPathGeoProc::makeProgramImpl(
const GrShaderCaps&) const {
return std::make_unique<Impl>();
}
///////////////////////////////////////////////////////////////////////////////
GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldPathGeoProc)
#if GR_TEST_UTILS
GrGeometryProcessor* GrDistanceFieldPathGeoProc::TestCreate(GrProcessorTestData* d) {
auto [view, ct, at] = d->randomAlphaOnlyView();
GrSamplerState::WrapMode wrapModes[2];
GrTest::TestWrapModes(d->fRandom, wrapModes);
GrSamplerState samplerState(wrapModes, d->fRandom->nextBool()
? GrSamplerState::Filter::kLinear
: GrSamplerState::Filter::kNearest);
uint32_t flags = 0;
flags |= d->fRandom->nextBool() ? kSimilarity_DistanceFieldEffectFlag : 0;
if (flags & kSimilarity_DistanceFieldEffectFlag) {
flags |= d->fRandom->nextBool() ? kScaleOnly_DistanceFieldEffectFlag : 0;
}
flags |= d->fRandom->nextBool() ? kWideColor_DistanceFieldEffectFlag : 0;
SkMatrix localMatrix = GrTest::TestMatrix(d->fRandom);
return GrDistanceFieldPathGeoProc::Make(d->allocator(), *d->caps()->shaderCaps(),
&view, 1,
samplerState,
localMatrix,
flags);
}
#endif
///////////////////////////////////////////////////////////////////////////////
class GrDistanceFieldLCDTextGeoProc::Impl : public ProgramImpl {
public:
void setData(const GrGLSLProgramDataManager& pdman,
const GrShaderCaps& shaderCaps,
const GrGeometryProcessor& geomProc) override {
SkASSERT(fDistanceAdjustUni.isValid());
const GrDistanceFieldLCDTextGeoProc& dflcd = geomProc.cast<GrDistanceFieldLCDTextGeoProc>();
GrDistanceFieldLCDTextGeoProc::DistanceAdjust wa = dflcd.fDistanceAdjust;
if (wa != fDistanceAdjust) {
pdman.set3f(fDistanceAdjustUni, wa.fR, wa.fG, wa.fB);
fDistanceAdjust = wa;
}
const SkISize& atlasDimensions = dflcd.fAtlasDimensions;
SkASSERT(SkIsPow2(atlasDimensions.fWidth) && SkIsPow2(atlasDimensions.fHeight));
if (fAtlasDimensions != atlasDimensions) {
pdman.set2f(fAtlasDimensionsInvUniform,
1.0f / atlasDimensions.fWidth,
1.0f / atlasDimensions.fHeight);
fAtlasDimensions = atlasDimensions;
}
SetTransform(pdman, shaderCaps, fLocalMatrixUniform, dflcd.fLocalMatrix, &fLocalMatrix);
}
private:
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const GrDistanceFieldLCDTextGeoProc& dfTexEffect =
args.fGeomProc.cast<GrDistanceFieldLCDTextGeoProc>();
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
const char* atlasDimensionsInvName;
fAtlasDimensionsInvUniform = uniformHandler->addUniform(nullptr,
kVertex_GrShaderFlag,
SkSLType::kFloat2,
"AtlasDimensionsInv",
&atlasDimensionsInvName);
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
// setup pass through color
fragBuilder->codeAppendf("half4 %s;\n", args.fOutputColor);
varyingHandler->addPassThroughAttribute(dfTexEffect.fInColor.asShaderVar(),
args.fOutputColor);
// Setup position
gpArgs->fPositionVar = dfTexEffect.fInPosition.asShaderVar();
WriteLocalCoord(vertBuilder,
uniformHandler,
*args.fShaderCaps,
gpArgs,
dfTexEffect.fInPosition.asShaderVar(),
dfTexEffect.fLocalMatrix,
&fLocalMatrixUniform);
// set up varyings
GrGLSLVarying uv, texIdx, st;
append_index_uv_varyings(args,
dfTexEffect.numTextureSamplers(),
dfTexEffect.fInTextureCoords.name(),
atlasDimensionsInvName,
&uv,
&texIdx,
&st);
GrGLSLVarying delta(SkSLType::kFloat);
varyingHandler->addVarying("Delta", &delta);
if (dfTexEffect.fFlags & kBGR_DistanceFieldEffectFlag) {
vertBuilder->codeAppendf("%s = -%s.x/3.0;", delta.vsOut(), atlasDimensionsInvName);
} else {
vertBuilder->codeAppendf("%s = %s.x/3.0;", delta.vsOut(), atlasDimensionsInvName);
}
// add frag shader code
bool isUniformScale = (dfTexEffect.fFlags & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfTexEffect.fFlags & kSimilarity_DistanceFieldEffectFlag );
bool isGammaCorrect = SkToBool(dfTexEffect.fFlags & kGammaCorrect_DistanceFieldEffectFlag);
// create LCD offset adjusted by inverse of transform
// Use highp to work around aliasing issues
fragBuilder->codeAppendf("float2 uv = %s;\n", uv.fsIn());
if (isUniformScale) {
if (args.fShaderCaps->fAvoidDfDxForGradientsWhenPossible) {
fragBuilder->codeAppendf("half st_grad_len = half(abs(dFdy(%s.y)));", st.fsIn());
} else {
fragBuilder->codeAppendf("half st_grad_len = half(abs(dFdx(%s.x)));", st.fsIn());
}
fragBuilder->codeAppendf("half2 offset = half2(half(st_grad_len*%s), 0.0);",
delta.fsIn());
} else if (isSimilarity) {
// For a similarity matrix with rotation, the gradient will not be aligned
// with the texel coordinate axes, so we need to calculate it.
if (args.fShaderCaps->fAvoidDfDxForGradientsWhenPossible) {
// We use dFdy instead and rotate -90 degrees to get the gradient in the x
// direction.
fragBuilder->codeAppendf("half2 st_grad = half2(dFdy(%s));", st.fsIn());
fragBuilder->codeAppendf("half2 offset = half2(%s*float2(st_grad.y, -st_grad.x));",
delta.fsIn());
} else {
fragBuilder->codeAppendf("half2 st_grad = half2(dFdx(%s));", st.fsIn());
fragBuilder->codeAppendf("half2 offset = half(%s)*st_grad;", delta.fsIn());
}
fragBuilder->codeAppend("half st_grad_len = length(st_grad);");
} else {
fragBuilder->codeAppendf("half2 st = half2(%s);\n", st.fsIn());
fragBuilder->codeAppend("half2 Jdx = half2(dFdx(st));");
fragBuilder->codeAppend("half2 Jdy = half2(dFdy(st));");
fragBuilder->codeAppendf("half2 offset = half2(half(%s))*Jdx;", delta.fsIn());
}
// sample the texture by index
fragBuilder->codeAppend("half4 texColor;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv", "texColor");
// green is distance to uv center
fragBuilder->codeAppend("half3 distance;");
fragBuilder->codeAppend("distance.y = texColor.r;");
// red is distance to left offset
fragBuilder->codeAppend("half2 uv_adjusted = half2(uv) - offset;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv_adjusted", "texColor");
fragBuilder->codeAppend("distance.x = texColor.r;");
// blue is distance to right offset
fragBuilder->codeAppend("uv_adjusted = half2(uv) + offset;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv_adjusted", "texColor");
fragBuilder->codeAppend("distance.z = texColor.r;");
fragBuilder->codeAppend("distance = "
"half3(" SK_DistanceFieldMultiplier ")*(distance - half3(" SK_DistanceFieldThreshold"));");
// adjust width based on gamma
const char* distanceAdjustUniName = nullptr;
fDistanceAdjustUni = uniformHandler->addUniform(nullptr, kFragment_GrShaderFlag,
SkSLType::kHalf3, "DistanceAdjust",
&distanceAdjustUniName);
fragBuilder->codeAppendf("distance -= %s;", distanceAdjustUniName);
// To be strictly correct, we should compute the anti-aliasing factor separately
// for each color component. However, this is only important when using perspective
// transformations, and even then using a single factor seems like a reasonable
// trade-off between quality and speed.
fragBuilder->codeAppend("half afwidth;");
if (isSimilarity) {
// For similarity transform (uniform scale-only is a subset of this), we adjust for the
// effect of the transformation on the distance by using the length of the gradient of
// the texture coordinates. We use st coordinates to ensure we're mapping 1:1 from texel
// space to pixel space.
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*st_grad_len;");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("half2 dist_grad = half2(half(dFdx(distance.r)), "
"half(dFdy(distance.r)));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("half dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = half2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*half(inversesqrt(dg_len2));");
fragBuilder->codeAppend("}");
fragBuilder->codeAppend("half2 grad = half2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
// The smoothstep falloff compensates for the non-linear sRGB response curve. If we are
// doing gamma-correct rendering (to an sRGB or F16 buffer), then we actually want distance
// mapped linearly to coverage, so use a linear step:
if (isGammaCorrect) {
fragBuilder->codeAppendf("half4 %s = "
"half4(saturate((distance + half3(afwidth)) / half3(2.0 * afwidth)), 1.0);",
args.fOutputCoverage);
} else {
fragBuilder->codeAppendf(
"half4 %s = half4(smoothstep(half3(-afwidth), half3(afwidth), distance), 1.0);",
args.fOutputCoverage);
}
}
private:
DistanceAdjust fDistanceAdjust = DistanceAdjust::Make(1.0f, 1.0f, 1.0f);
SkISize fAtlasDimensions = {-1, -1};
SkMatrix fLocalMatrix = SkMatrix::InvalidMatrix();
UniformHandle fDistanceAdjustUni;
UniformHandle fAtlasDimensionsInvUniform;
UniformHandle fLocalMatrixUniform;
};
///////////////////////////////////////////////////////////////////////////////
GrDistanceFieldLCDTextGeoProc::GrDistanceFieldLCDTextGeoProc(const GrShaderCaps& caps,
const GrSurfaceProxyView* views,
int numViews,
GrSamplerState params,
DistanceAdjust distanceAdjust,
uint32_t flags,
const SkMatrix& localMatrix)
: INHERITED(kGrDistanceFieldLCDTextGeoProc_ClassID)
, fLocalMatrix(localMatrix)
, fDistanceAdjust(distanceAdjust)
, fFlags(flags & kLCD_DistanceFieldEffectMask) {
SkASSERT(numViews <= kMaxTextures);
SkASSERT(!(flags & ~kLCD_DistanceFieldEffectMask) && (flags & kUseLCD_DistanceFieldEffectFlag));
if (fFlags & kPerspective_DistanceFieldEffectFlag) {
fInPosition = {"inPosition", kFloat3_GrVertexAttribType, SkSLType::kFloat3};
} else {
fInPosition = {"inPosition", kFloat2_GrVertexAttribType, SkSLType::kFloat2};
}
fInColor = {"inColor", kUByte4_norm_GrVertexAttribType, SkSLType::kHalf4};
fInTextureCoords = {"inTextureCoords", kUShort2_GrVertexAttribType,
caps.fIntegerSupport ? SkSLType::kUShort2 : SkSLType::kFloat2};
this->setVertexAttributesWithImplicitOffsets(&fInPosition, 3);
if (numViews) {
fAtlasDimensions = views[0].proxy()->dimensions();
}
for (int i = 0; i < numViews; ++i) {
const GrSurfaceProxy* proxy = views[i].proxy();
SkASSERT(proxy);
SkASSERT(proxy->dimensions() == fAtlasDimensions);
fTextureSamplers[i].reset(params, proxy->backendFormat(), views[i].swizzle());
}
this->setTextureSamplerCnt(numViews);
}
void GrDistanceFieldLCDTextGeoProc::addNewViews(const GrSurfaceProxyView* views,
int numViews,
GrSamplerState params) {
SkASSERT(numViews <= kMaxTextures);
// Just to make sure we don't try to add too many proxies
numViews = std::min(numViews, kMaxTextures);
if (!fTextureSamplers[0].isInitialized()) {
fAtlasDimensions = views[0].proxy()->dimensions();
}
for (int i = 0; i < numViews; ++i) {
const GrSurfaceProxy* proxy = views[i].proxy();
SkASSERT(proxy);
SkASSERT(proxy->dimensions() == fAtlasDimensions);
if (!fTextureSamplers[i].isInitialized()) {
fTextureSamplers[i].reset(params, proxy->backendFormat(), views[i].swizzle());
}
}
this->setTextureSamplerCnt(numViews);
}
void GrDistanceFieldLCDTextGeoProc::addToKey(const GrShaderCaps& caps,
skgpu::KeyBuilder* b) const {
uint32_t key = 0;
key |= ProgramImpl::ComputeMatrixKey(caps, fLocalMatrix);
key |= fFlags << 16;
b->add32(key);
b->add32(this->numTextureSamplers());
}
std::unique_ptr<GrGeometryProcessor::ProgramImpl> GrDistanceFieldLCDTextGeoProc::makeProgramImpl(
const GrShaderCaps&) const {
return std::make_unique<Impl>();
}
///////////////////////////////////////////////////////////////////////////////
GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldLCDTextGeoProc)
#if GR_TEST_UTILS
GrGeometryProcessor* GrDistanceFieldLCDTextGeoProc::TestCreate(GrProcessorTestData* d) {
auto [view, ct, at] = d->randomView();
GrSamplerState::WrapMode wrapModes[2];
GrTest::TestWrapModes(d->fRandom, wrapModes);
GrSamplerState samplerState(wrapModes, d->fRandom->nextBool()
? GrSamplerState::Filter::kLinear
: GrSamplerState::Filter::kNearest);
DistanceAdjust wa = { 0.0f, 0.1f, -0.1f };
uint32_t flags = kUseLCD_DistanceFieldEffectFlag;
flags |= d->fRandom->nextBool() ? kSimilarity_DistanceFieldEffectFlag : 0;
if (flags & kSimilarity_DistanceFieldEffectFlag) {
flags |= d->fRandom->nextBool() ? kScaleOnly_DistanceFieldEffectFlag : 0;
}
flags |= d->fRandom->nextBool() ? kBGR_DistanceFieldEffectFlag : 0;
SkMatrix localMatrix = GrTest::TestMatrix(d->fRandom);
return GrDistanceFieldLCDTextGeoProc::Make(d->allocator(), *d->caps()->shaderCaps(), &view,
1, samplerState, wa, flags, localMatrix);
}
#endif
#endif // !defined(SK_DISABLE_SDF_TEXT)