blob: 2b2beaa4c5fbeaf184c71c978f610257416aeb27 [file] [log] [blame]
/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "src/gpu/effects/GrTextureEffect.h"
#include "src/core/SkMatrixPriv.h"
#include "src/gpu/GrTexture.h"
#include "src/gpu/effects/GrMatrixEffect.h"
#include "src/gpu/glsl/GrGLSLProgramBuilder.h"
#include "src/sksl/SkSLUtil.h"
using Wrap = GrSamplerState::WrapMode;
using Filter = GrSamplerState::Filter;
using MipmapMode = GrSamplerState::MipmapMode;
struct GrTextureEffect::Sampling {
GrSamplerState fHWSampler;
ShaderMode fShaderModes[2] = {ShaderMode::kNone, ShaderMode::kNone};
SkRect fShaderSubset = {0, 0, 0, 0};
SkRect fShaderClamp = {0, 0, 0, 0};
float fBorder[4] = {0, 0, 0, 0};
Sampling(Filter filter, MipmapMode mm) : fHWSampler(filter, mm) {}
Sampling(const GrSurfaceProxy& proxy,
GrSamplerState wrap,
const SkRect&,
const SkRect*,
const float border[4],
bool alwaysUseShaderTileMode,
const GrCaps&,
SkVector linearFilterInset = {0.5f, 0.5f});
inline bool hasBorderAlpha() const;
};
GrTextureEffect::Sampling::Sampling(const GrSurfaceProxy& proxy,
GrSamplerState sampler,
const SkRect& subset,
const SkRect* domain,
const float border[4],
bool alwaysUseShaderTileMode,
const GrCaps& caps,
SkVector linearFilterInset) {
struct Span {
float fA = 0.f, fB = 0.f;
Span makeInset(float o) const {
Span r = {fA + o, fB - o};
if (r.fA > r.fB) {
r.fA = r.fB = (r.fA + r.fB) / 2;
}
return r;
}
bool contains(Span r) const { return fA <= r.fA && fB >= r.fB; }
};
struct Result1D {
ShaderMode fShaderMode;
Span fShaderSubset;
Span fShaderClamp;
Wrap fHWWrap;
};
auto type = proxy.asTextureProxy()->textureType();
auto filter = sampler.filter();
auto mm = sampler.mipmapMode();
auto resolve = [&](int size, Wrap wrap, Span subset, Span domain, float linearFilterInset) {
Result1D r;
bool canDoModeInHW = !alwaysUseShaderTileMode;
// TODO: Use HW border color when available.
if (wrap == Wrap::kClampToBorder &&
(!caps.clampToBorderSupport() || border[0] || border[1] || border[2] || border[3])) {
canDoModeInHW = false;
} else if (wrap != Wrap::kClamp && !caps.npotTextureTileSupport() && !SkIsPow2(size)) {
canDoModeInHW = false;
} else if (type != GrTextureType::k2D &&
!(wrap == Wrap::kClamp || wrap == Wrap::kClampToBorder)) {
canDoModeInHW = false;
}
if (canDoModeInHW && size > 0 && subset.fA <= 0 && subset.fB >= size) {
r.fShaderMode = ShaderMode::kNone;
r.fHWWrap = wrap;
r.fShaderSubset = r.fShaderClamp = {0, 0};
return r;
}
r.fShaderSubset = subset;
bool domainIsSafe = false;
if (filter == Filter::kNearest) {
Span isubset{sk_float_floor(subset.fA), sk_float_ceil(subset.fB)};
if (domain.fA > isubset.fA && domain.fB < isubset.fB) {
domainIsSafe = true;
}
// This inset prevents sampling neighboring texels that could occur when
// texture coords fall exactly at texel boundaries (depending on precision
// and GPU-specific snapping at the boundary).
r.fShaderClamp = isubset.makeInset(0.5f);
} else {
r.fShaderClamp = subset.makeInset(linearFilterInset);
if (r.fShaderClamp.contains(domain)) {
domainIsSafe = true;
}
}
if (!alwaysUseShaderTileMode && domainIsSafe) {
// The domain of coords that will be used won't access texels outside of the subset.
// So the wrap mode effectively doesn't matter. We use kClamp since it is always
// supported.
r.fShaderMode = ShaderMode::kNone;
r.fHWWrap = Wrap::kClamp;
r.fShaderSubset = r.fShaderClamp = {0, 0};
return r;
}
r.fShaderMode = GetShaderMode(wrap, filter, mm);
r.fHWWrap = Wrap::kClamp;
return r;
};
SkISize dim = proxy.isFullyLazy() ? SkISize{-1, -1} : proxy.backingStoreDimensions();
Span subsetX{subset.fLeft, subset.fRight};
auto domainX = domain ? Span{domain->fLeft, domain->fRight}
: Span{SK_FloatNegativeInfinity, SK_FloatInfinity};
auto x = resolve(dim.width(), sampler.wrapModeX(), subsetX, domainX, linearFilterInset.fX);
Span subsetY{subset.fTop, subset.fBottom};
auto domainY = domain ? Span{domain->fTop, domain->fBottom}
: Span{SK_FloatNegativeInfinity, SK_FloatInfinity};
auto y = resolve(dim.height(), sampler.wrapModeY(), subsetY, domainY, linearFilterInset.fY);
fHWSampler = {x.fHWWrap, y.fHWWrap, filter, mm};
fShaderModes[0] = x.fShaderMode;
fShaderModes[1] = y.fShaderMode;
fShaderSubset = {x.fShaderSubset.fA, y.fShaderSubset.fA,
x.fShaderSubset.fB, y.fShaderSubset.fB};
fShaderClamp = {x.fShaderClamp.fA, y.fShaderClamp.fA,
x.fShaderClamp.fB, y.fShaderClamp.fB};
std::copy_n(border, 4, fBorder);
}
bool GrTextureEffect::Sampling::hasBorderAlpha() const {
if (fHWSampler.wrapModeX() == Wrap::kClampToBorder ||
fHWSampler.wrapModeY() == Wrap::kClampToBorder) {
return true;
}
if (ShaderModeIsClampToBorder(fShaderModes[0]) || ShaderModeIsClampToBorder(fShaderModes[1])) {
return fBorder[3] < 1.f;
}
return false;
}
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::Make(GrSurfaceProxyView view,
SkAlphaType alphaType,
const SkMatrix& matrix,
Filter filter,
MipmapMode mm) {
Sampling sampling = Sampling(filter, mm);
std::unique_ptr<GrFragmentProcessor> te(new GrTextureEffect(std::move(view),
alphaType,
sampling));
return GrMatrixEffect::Make(matrix, std::move(te));
}
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::Make(GrSurfaceProxyView view,
SkAlphaType alphaType,
const SkMatrix& matrix,
GrSamplerState sampler,
const GrCaps& caps,
const float border[4]) {
Sampling sampling(*view.proxy(),
sampler,
SkRect::Make(view.proxy()->dimensions()),
nullptr,
border,
false,
caps);
std::unique_ptr<GrFragmentProcessor> te(new GrTextureEffect(std::move(view),
alphaType,
sampling));
return GrMatrixEffect::Make(matrix, std::move(te));
}
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::MakeSubset(GrSurfaceProxyView view,
SkAlphaType alphaType,
const SkMatrix& matrix,
GrSamplerState sampler,
const SkRect& subset,
const GrCaps& caps,
const float border[4],
bool alwaysUseShaderTileMode) {
Sampling sampling(*view.proxy(),
sampler,
subset,
nullptr,
border,
alwaysUseShaderTileMode,
caps);
std::unique_ptr<GrFragmentProcessor> te(new GrTextureEffect(std::move(view),
alphaType,
sampling));
return GrMatrixEffect::Make(matrix, std::move(te));
}
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::MakeSubset(GrSurfaceProxyView view,
SkAlphaType alphaType,
const SkMatrix& matrix,
GrSamplerState sampler,
const SkRect& subset,
const SkRect& domain,
const GrCaps& caps,
const float border[4]) {
Sampling sampling(*view.proxy(), sampler, subset, &domain, border, false, caps);
std::unique_ptr<GrFragmentProcessor> te(new GrTextureEffect(std::move(view),
alphaType,
sampling));
return GrMatrixEffect::Make(matrix, std::move(te));
}
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::MakeCustomLinearFilterInset(
GrSurfaceProxyView view,
SkAlphaType alphaType,
const SkMatrix& matrix,
Wrap wx,
Wrap wy,
const SkRect& subset,
const SkRect* domain,
SkVector inset,
const GrCaps& caps,
const float border[4]) {
GrSamplerState sampler(wx, wy, Filter::kLinear);
Sampling sampling(*view.proxy(), sampler, subset, domain, border, false, caps, inset);
std::unique_ptr<GrFragmentProcessor> te(new GrTextureEffect(std::move(view),
alphaType,
sampling));
return GrMatrixEffect::Make(matrix, std::move(te));
}
SkMatrix GrTextureEffect::coordAdjustmentMatrix() const {
SkMatrix m;
GrTexture* texture = this->texture();
SkISize d = texture->dimensions();
if (this->matrixEffectShouldNormalize()) {
if (fView.origin() == kBottomLeft_GrSurfaceOrigin) {
m.setScaleTranslate(1.f / d.width(), -1.f / d.height(), 0, 1);
} else {
m.setScale(1.f / d.width(), 1.f / d.height());
}
} else {
if (fView.origin() == kBottomLeft_GrSurfaceOrigin) {
m.setScaleTranslate(1.f, -1.f, 0, d.height());
}
}
return m;
}
GrTextureEffect::ShaderMode GrTextureEffect::GetShaderMode(Wrap wrap,
Filter filter,
MipmapMode mm) {
switch (wrap) {
case Wrap::kMirrorRepeat:
return ShaderMode::kMirrorRepeat;
case Wrap::kClamp:
return ShaderMode::kClamp;
case Wrap::kRepeat:
switch (mm) {
case MipmapMode::kNone:
switch (filter) {
case Filter::kNearest: return ShaderMode::kRepeat_Nearest_None;
case Filter::kLinear: return ShaderMode::kRepeat_Linear_None;
}
SkUNREACHABLE;
case MipmapMode::kNearest:
case MipmapMode::kLinear:
switch (filter) {
case Filter::kNearest: return ShaderMode::kRepeat_Nearest_Mipmap;
case Filter::kLinear: return ShaderMode::kRepeat_Linear_Mipmap;
}
SkUNREACHABLE;
}
SkUNREACHABLE;
case Wrap::kClampToBorder:
return filter == Filter::kNearest ? ShaderMode::kClampToBorder_Nearest
: ShaderMode::kClampToBorder_Filter;
}
SkUNREACHABLE;
}
inline bool GrTextureEffect::ShaderModeIsClampToBorder(ShaderMode m) {
return m == ShaderMode::kClampToBorder_Nearest || m == ShaderMode::kClampToBorder_Filter;
}
bool GrTextureEffect::ShaderModeRequiresUnormCoord(ShaderMode m) {
switch (m) {
case ShaderMode::kNone: return false;
case ShaderMode::kClamp: return false;
case ShaderMode::kRepeat_Nearest_None: return false;
case ShaderMode::kRepeat_Linear_None: return true;
case ShaderMode::kRepeat_Nearest_Mipmap: return true;
case ShaderMode::kRepeat_Linear_Mipmap: return true;
case ShaderMode::kMirrorRepeat: return false;
case ShaderMode::kClampToBorder_Nearest: return true;
case ShaderMode::kClampToBorder_Filter: return true;
}
SkUNREACHABLE;
};
void GrTextureEffect::Impl::emitCode(EmitArgs& args) {
using ShaderMode = GrTextureEffect::ShaderMode;
auto& te = args.fFp.cast<GrTextureEffect>();
auto* fb = args.fFragBuilder;
if (te.fShaderModes[0] == ShaderMode::kNone &&
te.fShaderModes[1] == ShaderMode::kNone) {
fb->codeAppendf("return ");
fb->appendTextureLookup(fSamplerHandle, args.fSampleCoord);
fb->codeAppendf(";");
} else {
// Here is the basic flow of the various ShaderModes are implemented in a series of
// steps. Not all the steps apply to all the modes. We try to emit only the steps
// that are necessary for the given x/y shader modes.
//
// 0) Start with interpolated coordinates (unnormalize if doing anything
// complicated).
// 1) Map the coordinates into the subset range [Repeat and MirrorRepeat], or pass
// through output of 0).
// 2) Clamp the coordinates to a 0.5 inset of the subset rect [Clamp, Repeat, and
// MirrorRepeat always or ClampToBorder only when filtering] or pass through
// output of 1). The clamp rect collapses to a line or point it if the subset
// rect is less than one pixel wide/tall.
// 3) Look up texture with output of 2) [All]
// 3) Use the difference between 1) and 2) to apply filtering at edge [Repeat or
// ClampToBorder]. In the Repeat case this requires extra texture lookups on the
// other side of the subset (up to 3 more reads). Or if ClampToBorder and not
// filtering do a hard less than/greater than test with the subset rect.
// Convert possible projective texture coordinates into non-homogeneous half2.
fb->codeAppendf("float2 inCoord = %s;", args.fSampleCoord);
const auto& m = te.fShaderModes;
const char* borderName = nullptr;
if (te.hasClampToBorderShaderMode()) {
fBorderUni = args.fUniformHandler->addUniform(
&te, kFragment_GrShaderFlag, kHalf4_GrSLType, "border", &borderName);
}
auto modeUsesSubset = [](ShaderMode m) {
switch (m) {
case ShaderMode::kNone: return false;
case ShaderMode::kClamp: return false;
case ShaderMode::kRepeat_Nearest_None: return true;
case ShaderMode::kRepeat_Linear_None: return true;
case ShaderMode::kRepeat_Nearest_Mipmap: return true;
case ShaderMode::kRepeat_Linear_Mipmap: return true;
case ShaderMode::kMirrorRepeat: return true;
case ShaderMode::kClampToBorder_Nearest: return true;
case ShaderMode::kClampToBorder_Filter: return true;
}
SkUNREACHABLE;
};
auto modeUsesClamp = [](ShaderMode m) {
switch (m) {
case ShaderMode::kNone: return false;
case ShaderMode::kClamp: return true;
case ShaderMode::kRepeat_Nearest_None: return true;
case ShaderMode::kRepeat_Linear_None: return true;
case ShaderMode::kRepeat_Nearest_Mipmap: return true;
case ShaderMode::kRepeat_Linear_Mipmap: return true;
case ShaderMode::kMirrorRepeat: return true;
case ShaderMode::kClampToBorder_Nearest: return false;
case ShaderMode::kClampToBorder_Filter: return true;
}
SkUNREACHABLE;
};
bool useSubset[2] = {modeUsesSubset(m[0]), modeUsesSubset(m[1])};
bool useClamp [2] = {modeUsesClamp (m[0]), modeUsesClamp (m[1])};
const char* subsetName = nullptr;
if (useSubset[0] || useSubset[1]) {
fSubsetUni = args.fUniformHandler->addUniform(
&te, kFragment_GrShaderFlag, kFloat4_GrSLType, "subset", &subsetName);
}
const char* clampName = nullptr;
if (useClamp[0] || useClamp[1]) {
fClampUni = args.fUniformHandler->addUniform(
&te, kFragment_GrShaderFlag, kFloat4_GrSLType, "clamp", &clampName);
}
bool unormCoordsRequiredForShaderMode = ShaderModeRequiresUnormCoord(m[0]) ||
ShaderModeRequiresUnormCoord(m[1]);
// We should not pre-normalize the input coords with GrMatrixEffect if we're going to
// operate on unnormalized coords and then normalize after the shader mode.
SkASSERT(!(unormCoordsRequiredForShaderMode && te.matrixEffectShouldNormalize()));
bool sampleCoordsMustBeNormalized =
te.fView.asTextureProxy()->textureType() != GrTextureType::kRectangle;
const char* idims = nullptr;
if (unormCoordsRequiredForShaderMode && sampleCoordsMustBeNormalized) {
// TODO: Detect support for textureSize() or polyfill textureSize() in SkSL and
// always use?
fIDimsUni = args.fUniformHandler->addUniform(&te, kFragment_GrShaderFlag,
kFloat2_GrSLType, "idims", &idims);
}
// Generates a string to read at a coordinate, normalizing coords if necessary.
auto read = [&](const char* coord) {
SkString result;
SkString normCoord;
if (idims) {
normCoord.printf("(%s) * %s", coord, idims);
} else {
normCoord = coord;
}
fb->appendTextureLookup(&result, fSamplerHandle, normCoord.c_str());
return result;
};
// Implements coord wrapping for kRepeat and kMirrorRepeat
auto subsetCoord = [&](ShaderMode mode,
const char* coordSwizzle,
const char* subsetStartSwizzle,
const char* subsetStopSwizzle,
const char* extraCoord,
const char* coordWeight) {
switch (mode) {
// These modes either don't use the subset rect or don't need to map the
// coords to be within the subset.
case ShaderMode::kNone:
case ShaderMode::kClampToBorder_Nearest:
case ShaderMode::kClampToBorder_Filter:
case ShaderMode::kClamp:
fb->codeAppendf("subsetCoord.%s = inCoord.%s;", coordSwizzle, coordSwizzle);
break;
case ShaderMode::kRepeat_Nearest_None:
case ShaderMode::kRepeat_Linear_None:
fb->codeAppendf(
"subsetCoord.%s = mod(inCoord.%s - %s.%s, %s.%s - %s.%s) + %s.%s;",
coordSwizzle, coordSwizzle, subsetName, subsetStartSwizzle, subsetName,
subsetStopSwizzle, subsetName, subsetStartSwizzle, subsetName,
subsetStartSwizzle);
break;
case ShaderMode::kRepeat_Nearest_Mipmap:
case ShaderMode::kRepeat_Linear_Mipmap:
// The approach here is to generate two sets of texture coords that
// are both "moving" at the same speed (if not direction) as
// inCoords. We accomplish that by using two out of phase mirror
// repeat coords. We will always sample using both coords but the
// read from the upward sloping one is selected using a weight
// that transitions from one set to the other near the reflection
// point. Like the coords, the weight is a saw-tooth function,
// phase-shifted, vertically translated, and then clamped to 0..1.
// TODO: Skip this and use textureGrad() when available.
SkASSERT(extraCoord);
SkASSERT(coordWeight);
fb->codeAppend("{");
fb->codeAppendf("float w = %s.%s - %s.%s;", subsetName, subsetStopSwizzle,
subsetName, subsetStartSwizzle);
fb->codeAppendf("float w2 = 2 * w;");
fb->codeAppendf("float d = inCoord.%s - %s.%s;", coordSwizzle, subsetName,
subsetStartSwizzle);
fb->codeAppend("float m = mod(d, w2);");
fb->codeAppend("float o = mix(m, w2 - m, step(w, m));");
fb->codeAppendf("subsetCoord.%s = o + %s.%s;", coordSwizzle, subsetName,
subsetStartSwizzle);
fb->codeAppendf("%s = w - o + %s.%s;", extraCoord, subsetName,
subsetStartSwizzle);
// coordWeight is used as the third param of mix() to blend between a
// sample taken using subsetCoord and a sample at extraCoord.
fb->codeAppend("float hw = w/2;");
fb->codeAppend("float n = mod(d - hw, w2);");
fb->codeAppendf("%s = saturate(half(mix(n, w2 - n, step(w, n)) - hw + 0.5));",
coordWeight);
fb->codeAppend("}");
break;
case ShaderMode::kMirrorRepeat:
fb->codeAppend("{");
fb->codeAppendf("float w = %s.%s - %s.%s;", subsetName, subsetStopSwizzle,
subsetName, subsetStartSwizzle);
fb->codeAppendf("float w2 = 2 * w;");
fb->codeAppendf("float m = mod(inCoord.%s - %s.%s, w2);", coordSwizzle,
subsetName, subsetStartSwizzle);
fb->codeAppendf("subsetCoord.%s = mix(m, w2 - m, step(w, m)) + %s.%s;",
coordSwizzle, subsetName, subsetStartSwizzle);
fb->codeAppend("}");
break;
}
};
auto clampCoord = [&](bool clamp,
const char* coordSwizzle,
const char* clampStartSwizzle,
const char* clampStopSwizzle) {
if (clamp) {
fb->codeAppendf("clampedCoord%s = clamp(subsetCoord%s, %s%s, %s%s);",
coordSwizzle, coordSwizzle, clampName, clampStartSwizzle, clampName,
clampStopSwizzle);
} else {
fb->codeAppendf("clampedCoord%s = subsetCoord%s;", coordSwizzle, coordSwizzle);
}
};
// Insert vars for extra coords and blending weights for repeat + mip map.
const char* extraRepeatCoordX = nullptr;
const char* repeatCoordWeightX = nullptr;
const char* extraRepeatCoordY = nullptr;
const char* repeatCoordWeightY = nullptr;
bool mipmapRepeatX = m[0] == ShaderMode::kRepeat_Nearest_Mipmap ||
m[0] == ShaderMode::kRepeat_Linear_Mipmap;
bool mipmapRepeatY = m[1] == ShaderMode::kRepeat_Nearest_Mipmap ||
m[1] == ShaderMode::kRepeat_Linear_Mipmap;
if (mipmapRepeatX || mipmapRepeatY) {
fb->codeAppend("float2 extraRepeatCoord;");
}
if (mipmapRepeatX) {
fb->codeAppend("half repeatCoordWeightX;");
extraRepeatCoordX = "extraRepeatCoord.x";
repeatCoordWeightX = "repeatCoordWeightX";
}
if (mipmapRepeatY) {
fb->codeAppend("half repeatCoordWeightY;");
extraRepeatCoordY = "extraRepeatCoord.y";
repeatCoordWeightY = "repeatCoordWeightY";
}
// Apply subset rect and clamp rect to coords.
fb->codeAppend("float2 subsetCoord;");
subsetCoord(te.fShaderModes[0], "x", "x", "z", extraRepeatCoordX, repeatCoordWeightX);
subsetCoord(te.fShaderModes[1], "y", "y", "w", extraRepeatCoordY, repeatCoordWeightY);
fb->codeAppend("float2 clampedCoord;");
if (useClamp[0] == useClamp[1]) {
clampCoord(useClamp[0], "", ".xy", ".zw");
} else {
clampCoord(useClamp[0], ".x", ".x", ".z");
clampCoord(useClamp[1], ".y", ".y", ".w");
}
// Additional clamping for the extra coords for kRepeat with mip maps.
if (mipmapRepeatX && mipmapRepeatY) {
fb->codeAppendf("extraRepeatCoord = clamp(extraRepeatCoord, %s.xy, %s.zw);",
clampName, clampName);
} else if (mipmapRepeatX) {
fb->codeAppendf("extraRepeatCoord.x = clamp(extraRepeatCoord.x, %s.x, %s.z);",
clampName, clampName);
} else if (mipmapRepeatY) {
fb->codeAppendf("extraRepeatCoord.y = clamp(extraRepeatCoord.y, %s.y, %s.w);",
clampName, clampName);
}
// Do the 2 or 4 texture reads for kRepeatMipMap and then apply the weight(s)
// to blend between them. If neither direction is repeat or not using mip maps do a single
// read at clampedCoord.
if (mipmapRepeatX && mipmapRepeatY) {
fb->codeAppendf(
"half4 textureColor ="
" mix(mix(%s, %s, repeatCoordWeightX),"
" mix(%s, %s, repeatCoordWeightX),"
" repeatCoordWeightY);",
read("clampedCoord").c_str(),
read("float2(extraRepeatCoord.x, clampedCoord.y)").c_str(),
read("float2(clampedCoord.x, extraRepeatCoord.y)").c_str(),
read("float2(extraRepeatCoord.x, extraRepeatCoord.y)").c_str());
} else if (mipmapRepeatX) {
fb->codeAppendf("half4 textureColor = mix(%s, %s, repeatCoordWeightX);",
read("clampedCoord").c_str(),
read("float2(extraRepeatCoord.x, clampedCoord.y)").c_str());
} else if (mipmapRepeatY) {
fb->codeAppendf("half4 textureColor = mix(%s, %s, repeatCoordWeightY);",
read("clampedCoord").c_str(),
read("float2(clampedCoord.x, extraRepeatCoord.y)").c_str());
} else {
fb->codeAppendf("half4 textureColor = %s;", read("clampedCoord").c_str());
}
// Strings for extra texture reads used only in kRepeatLinear
SkString repeatLinearReadX;
SkString repeatLinearReadY;
// Calculate the amount the coord moved for clamping. This will be used
// to implement shader-based filtering for kClampToBorder and kRepeat.
bool repeatLinearFilterX = m[0] == ShaderMode::kRepeat_Linear_None ||
m[0] == ShaderMode::kRepeat_Linear_Mipmap;
bool repeatLinearFilterY = m[1] == ShaderMode::kRepeat_Linear_None ||
m[1] == ShaderMode::kRepeat_Linear_Mipmap;
if (repeatLinearFilterX || m[0] == ShaderMode::kClampToBorder_Filter) {
fb->codeAppend("half errX = half(subsetCoord.x - clampedCoord.x);");
if (repeatLinearFilterX) {
fb->codeAppendf("float repeatCoordX = errX > 0 ? %s.x : %s.z;",
clampName, clampName);
repeatLinearReadX = read("float2(repeatCoordX, clampedCoord.y)");
}
}
if (repeatLinearFilterY || m[1] == ShaderMode::kClampToBorder_Filter) {
fb->codeAppend("half errY = half(subsetCoord.y - clampedCoord.y);");
if (repeatLinearFilterY) {
fb->codeAppendf("float repeatCoordY = errY > 0 ? %s.y : %s.w;",
clampName, clampName);
repeatLinearReadY = read("float2(clampedCoord.x, repeatCoordY)");
}
}
// Add logic for kRepeat + linear filter. Do 1 or 3 more texture reads depending
// on whether both modes are kRepeat and whether we're near a single subset edge
// or a corner. Then blend the multiple reads using the err values calculated
// above.
const char* ifStr = "if";
if (repeatLinearFilterX && repeatLinearFilterY) {
auto repeatLinearReadXY = read("float2(repeatCoordX, repeatCoordY)");
fb->codeAppendf(
"if (errX != 0 && errY != 0) {"
" errX = abs(errX);"
" textureColor = mix(mix(textureColor, %s, errX),"
" mix(%s, %s, errX),"
" abs(errY));"
"}",
repeatLinearReadX.c_str(), repeatLinearReadY.c_str(),
repeatLinearReadXY.c_str());
ifStr = "else if";
}
if (repeatLinearFilterX) {
fb->codeAppendf(
"%s (errX != 0) {"
" textureColor = mix(textureColor, %s, abs(errX));"
"}",
ifStr, repeatLinearReadX.c_str());
}
if (repeatLinearFilterY) {
fb->codeAppendf(
"%s (errY != 0) {"
" textureColor = mix(textureColor, %s, abs(errY));"
"}",
ifStr, repeatLinearReadY.c_str());
}
// Do soft edge shader filtering against border color for kClampToBorderFilter using
// the err values calculated above.
if (m[0] == ShaderMode::kClampToBorder_Filter) {
fb->codeAppendf("textureColor = mix(textureColor, %s, min(abs(errX), 1));", borderName);
}
if (m[1] == ShaderMode::kClampToBorder_Filter) {
fb->codeAppendf("textureColor = mix(textureColor, %s, min(abs(errY), 1));", borderName);
}
// Do hard-edge shader transition to border color for kClampToBorderNearest at the
// subset boundaries. Snap the input coordinates to nearest neighbor (with an
// epsilon) before comparing to the subset rect to avoid GPU interpolation errors
if (m[0] == ShaderMode::kClampToBorder_Nearest) {
fb->codeAppendf(
"float snappedX = floor(inCoord.x + 0.001) + 0.5;"
"if (snappedX < %s.x || snappedX > %s.z) {"
" textureColor = %s;"
"}",
subsetName, subsetName, borderName);
}
if (m[1] == ShaderMode::kClampToBorder_Nearest) {
fb->codeAppendf(
"float snappedY = floor(inCoord.y + 0.001) + 0.5;"
"if (snappedY < %s.y || snappedY > %s.w) {"
" textureColor = %s;"
"}",
subsetName, subsetName, borderName);
}
fb->codeAppendf("return textureColor;");
}
}
void GrTextureEffect::Impl::onSetData(const GrGLSLProgramDataManager& pdm,
const GrFragmentProcessor& fp) {
const auto& te = fp.cast<GrTextureEffect>();
const float w = te.texture()->width();
const float h = te.texture()->height();
const auto& s = te.fSubset;
const auto& c = te.fClamp;
auto type = te.texture()->textureType();
float idims[2] = {1.f/w, 1.f/h};
if (fIDimsUni.isValid()) {
pdm.set2fv(fIDimsUni, 1, idims);
SkASSERT(type != GrTextureType::kRectangle);
}
auto pushRect = [&](float rect[4], UniformHandle uni) {
if (te.view().origin() == kBottomLeft_GrSurfaceOrigin) {
rect[1] = h - rect[1];
rect[3] = h - rect[3];
std::swap(rect[1], rect[3]);
}
if (!fIDimsUni.isValid() && type != GrTextureType::kRectangle) {
rect[0] *= idims[0];
rect[2] *= idims[0];
rect[1] *= idims[1];
rect[3] *= idims[1];
}
pdm.set4fv(uni, 1, rect);
};
if (fSubsetUni.isValid()) {
float subset[] = {s.fLeft, s.fTop, s.fRight, s.fBottom};
pushRect(subset, fSubsetUni);
}
if (fClampUni.isValid()) {
float subset[] = {c.fLeft, c.fTop, c.fRight, c.fBottom};
pushRect(subset, fClampUni);
}
if (fBorderUni.isValid()) {
pdm.set4fv(fBorderUni, 1, te.fBorder);
}
}
std::unique_ptr<GrFragmentProcessor::ProgramImpl> GrTextureEffect::onMakeProgramImpl() const {
return std::make_unique<Impl>();
}
void GrTextureEffect::onAddToKey(const GrShaderCaps&, GrProcessorKeyBuilder* b) const {
auto m0 = static_cast<uint32_t>(fShaderModes[0]);
b->addBits(8, m0, "shaderMode0");
auto m1 = static_cast<uint32_t>(fShaderModes[1]);
b->addBits(8, m1, "shaderMode1");
}
bool GrTextureEffect::onIsEqual(const GrFragmentProcessor& other) const {
auto& that = other.cast<GrTextureEffect>();
if (fView != that.fView) {
return false;
}
if (fSamplerState != that.fSamplerState) {
return false;
}
if (fShaderModes[0] != that.fShaderModes[0] || fShaderModes[1] != that.fShaderModes[1]) {
return false;
}
if (fSubset != that.fSubset) {
return false;
}
if (this->hasClampToBorderShaderMode() && !std::equal(fBorder, fBorder + 4, that.fBorder)) {
return false;
}
return true;
}
bool GrTextureEffect::matrixEffectShouldNormalize() const {
return fView.asTextureProxy()->textureType() != GrTextureType::kRectangle &&
!ShaderModeRequiresUnormCoord(fShaderModes[0]) &&
!ShaderModeRequiresUnormCoord(fShaderModes[1]);
}
GrTextureEffect::GrTextureEffect(GrSurfaceProxyView view,
SkAlphaType alphaType,
const Sampling& sampling)
: GrFragmentProcessor(kGrTextureEffect_ClassID,
ModulateForSamplerOptFlags(alphaType, sampling.hasBorderAlpha()))
, fView(std::move(view))
, fSamplerState(sampling.fHWSampler)
, fSubset(sampling.fShaderSubset)
, fClamp(sampling.fShaderClamp)
, fShaderModes{sampling.fShaderModes[0], sampling.fShaderModes[1]} {
// We always compare the range even when it isn't used so assert we have canonical don't care
// values.
SkASSERT(fShaderModes[0] != ShaderMode::kNone || (fSubset.fLeft == 0 && fSubset.fRight == 0));
SkASSERT(fShaderModes[1] != ShaderMode::kNone || (fSubset.fTop == 0 && fSubset.fBottom == 0));
this->setUsesSampleCoordsDirectly();
std::copy_n(sampling.fBorder, 4, fBorder);
}
GrTextureEffect::GrTextureEffect(const GrTextureEffect& src)
: INHERITED(kGrTextureEffect_ClassID, src.optimizationFlags())
, fView(src.fView)
, fSamplerState(src.fSamplerState)
, fSubset(src.fSubset)
, fClamp(src.fClamp)
, fShaderModes{src.fShaderModes[0], src.fShaderModes[1]} {
std::copy_n(src.fBorder, 4, fBorder);
this->setUsesSampleCoordsDirectly();
}
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::clone() const {
return std::unique_ptr<GrFragmentProcessor>(new GrTextureEffect(*this));
}
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrTextureEffect);
#if GR_TEST_UTILS
std::unique_ptr<GrFragmentProcessor> GrTextureEffect::TestCreate(GrProcessorTestData* testData) {
auto [view, ct, at] = testData->randomView();
Wrap wrapModes[2];
GrTest::TestWrapModes(testData->fRandom, wrapModes);
Filter filter = testData->fRandom->nextBool() ? Filter::kLinear : Filter::kNearest;
MipmapMode mm = MipmapMode::kNone;
if (view.asTextureProxy()->mipmapped() == GrMipmapped::kYes) {
mm = testData->fRandom->nextBool() ? MipmapMode::kLinear : MipmapMode::kNone;
}
GrSamplerState params(wrapModes, filter, mm);
const SkMatrix& matrix = GrTest::TestMatrix(testData->fRandom);
return GrTextureEffect::Make(std::move(view), at, matrix, params, *testData->caps());
}
#endif