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/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "src/shaders/SkImageShader.h"
#include "src/base/SkArenaAlloc.h"
#include "src/core/SkColorSpacePriv.h"
#include "src/core/SkColorSpaceXformSteps.h"
#include "src/core/SkImageInfoPriv.h"
#include "src/core/SkMatrixPriv.h"
#include "src/core/SkMatrixProvider.h"
#include "src/core/SkMipmapAccessor.h"
#include "src/core/SkOpts.h"
#include "src/core/SkRasterPipeline.h"
#include "src/core/SkReadBuffer.h"
#include "src/core/SkVM.h"
#include "src/core/SkWriteBuffer.h"
#include "src/image/SkImage_Base.h"
#include "src/shaders/SkBitmapProcShader.h"
#include "src/shaders/SkLocalMatrixShader.h"
#include "src/shaders/SkTransformShader.h"
#if defined(SK_GRAPHITE)
#include "src/gpu/graphite/ImageUtils.h"
#include "src/gpu/graphite/Image_Graphite.h"
#include "src/gpu/graphite/KeyContext.h"
#include "src/gpu/graphite/KeyHelpers.h"
#include "src/gpu/graphite/Log.h"
#include "src/gpu/graphite/PaintParamsKey.h"
#include "src/gpu/graphite/ReadWriteSwizzle.h"
#include "src/gpu/graphite/TextureProxyView.h"
static skgpu::graphite::ReadSwizzle swizzle_class_to_read_enum(const skgpu::Swizzle& swizzle) {
if (swizzle == skgpu::Swizzle::RGBA()) {
return skgpu::graphite::ReadSwizzle::kRGBA;
} else if (swizzle == skgpu::Swizzle::RGB1()) {
return skgpu::graphite::ReadSwizzle::kRGB1;
} else if (swizzle == skgpu::Swizzle("rrrr")) {
return skgpu::graphite::ReadSwizzle::kRRRR;
} else if (swizzle == skgpu::Swizzle("rrr1")) {
return skgpu::graphite::ReadSwizzle::kRRR1;
} else if (swizzle == skgpu::Swizzle::BGRA()) {
return skgpu::graphite::ReadSwizzle::kBGRA;
} else {
SKGPU_LOG_W("%s is an unsupported read swizzle. Defaulting to RGBA.\n",
swizzle.asString().data());
return skgpu::graphite::ReadSwizzle::kRGBA;
}
}
#endif
SkM44 SkImageShader::CubicResamplerMatrix(float B, float C) {
#if 0
constexpr SkM44 kMitchell = SkM44( 1.f/18.f, -9.f/18.f, 15.f/18.f, -7.f/18.f,
16.f/18.f, 0.f/18.f, -36.f/18.f, 21.f/18.f,
1.f/18.f, 9.f/18.f, 27.f/18.f, -21.f/18.f,
0.f/18.f, 0.f/18.f, -6.f/18.f, 7.f/18.f);
constexpr SkM44 kCatmull = SkM44(0.0f, -0.5f, 1.0f, -0.5f,
1.0f, 0.0f, -2.5f, 1.5f,
0.0f, 0.5f, 2.0f, -1.5f,
0.0f, 0.0f, -0.5f, 0.5f);
if (B == 1.0f/3 && C == 1.0f/3) {
return kMitchell;
}
if (B == 0 && C == 0.5f) {
return kCatmull;
}
#endif
return SkM44( (1.f/6)*B, -(3.f/6)*B - C, (3.f/6)*B + 2*C, - (1.f/6)*B - C,
1 - (2.f/6)*B, 0, -3 + (12.f/6)*B + C, 2 - (9.f/6)*B - C,
(1.f/6)*B, (3.f/6)*B + C, 3 - (15.f/6)*B - 2*C, -2 + (9.f/6)*B + C,
0, 0, -C, (1.f/6)*B + C);
}
/**
* We are faster in clamp, so always use that tiling when we can.
*/
static SkTileMode optimize(SkTileMode tm, int dimension) {
SkASSERT(dimension > 0);
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
// need to update frameworks/base/libs/hwui/tests/unit/SkiaBehaviorTests.cpp:55 to allow
// for transforming to clamp.
return tm;
#else
// mirror and repeat on a 1px axis are the same as clamping, but decal will still transition to
// transparent black.
return (tm != SkTileMode::kDecal && dimension == 1) ? SkTileMode::kClamp : tm;
#endif
}
// TODO: currently this only *always* used in asFragmentProcessor(), which is excluded on no-gpu
// builds. No-gpu builds only use needs_subset() in asserts, so release+no-gpu doesn't use it, which
// can cause builds to fail if unused warnings are treated as errors.
[[maybe_unused]] static bool needs_subset(SkImage* img, const SkRect& subset) {
return subset != SkRect::Make(img->dimensions());
}
SkImageShader::SkImageShader(sk_sp<SkImage> img,
const SkRect& subset,
SkTileMode tmx, SkTileMode tmy,
const SkSamplingOptions& sampling,
bool raw,
bool clampAsIfUnpremul)
: fImage(std::move(img))
, fSampling(sampling)
, fTileModeX(optimize(tmx, fImage->width()))
, fTileModeY(optimize(tmy, fImage->height()))
, fSubset(subset)
, fRaw(raw)
, fClampAsIfUnpremul(clampAsIfUnpremul) {
// These options should never appear together:
SkASSERT(!fRaw || !fClampAsIfUnpremul);
// Bicubic filtering of raw image shaders would add a surprising clamp - so we don't support it
SkASSERT(!fRaw || !fSampling.useCubic);
}
// just used for legacy-unflattening
enum class LegacyFilterEnum {
kNone,
kLow,
kMedium,
kHigh,
// this is the special value for backward compatibility
kInheritFromPaint,
// this signals we should use the new SkFilterOptions
kUseFilterOptions,
// use cubic and ignore FilterOptions
kUseCubicResampler,
kLast = kUseCubicResampler,
};
// fClampAsIfUnpremul is always false when constructed through public APIs,
// so there's no need to read or write it here.
sk_sp<SkFlattenable> SkImageShader::CreateProc(SkReadBuffer& buffer) {
auto tmx = buffer.read32LE<SkTileMode>(SkTileMode::kLastTileMode);
auto tmy = buffer.read32LE<SkTileMode>(SkTileMode::kLastTileMode);
SkSamplingOptions sampling;
bool readSampling = true;
if (buffer.isVersionLT(SkPicturePriv::kNoFilterQualityShaders_Version) &&
!buffer.readBool() /* legacy has_sampling */)
{
readSampling = false;
// we just default to Nearest in sampling
}
if (readSampling) {
sampling = buffer.readSampling();
}
SkMatrix localMatrix;
if (buffer.isVersionLT(SkPicturePriv::Version::kNoShaderLocalMatrix)) {
buffer.readMatrix(&localMatrix);
}
sk_sp<SkImage> img = buffer.readImage();
if (!img) {
return nullptr;
}
bool raw = buffer.isVersionLT(SkPicturePriv::Version::kRawImageShaders) ? false
: buffer.readBool();
// TODO(skbug.com/12784): Subset is not serialized yet; it's only used by special images so it
// will never be written to an SKP.
return raw ? SkImageShader::MakeRaw(std::move(img), tmx, tmy, sampling, &localMatrix)
: SkImageShader::Make(std::move(img), tmx, tmy, sampling, &localMatrix);
}
void SkImageShader::flatten(SkWriteBuffer& buffer) const {
buffer.writeUInt((unsigned)fTileModeX);
buffer.writeUInt((unsigned)fTileModeY);
buffer.writeSampling(fSampling);
buffer.writeImage(fImage.get());
SkASSERT(fClampAsIfUnpremul == false);
// TODO(skbug.com/12784): Subset is not serialized yet; it's only used by special images so it
// will never be written to an SKP.
SkASSERT(!needs_subset(fImage.get(), fSubset));
buffer.writeBool(fRaw);
}
bool SkImageShader::isOpaque() const {
return fImage->isOpaque() &&
fTileModeX != SkTileMode::kDecal && fTileModeY != SkTileMode::kDecal;
}
#ifdef SK_ENABLE_LEGACY_SHADERCONTEXT
static bool legacy_shader_can_handle(const SkMatrix& inv) {
SkASSERT(!inv.hasPerspective());
// Scale+translate methods are always present, but affine might not be.
if (!SkOpts::S32_alpha_D32_filter_DXDY && !inv.isScaleTranslate()) {
return false;
}
// legacy code uses SkFixed 32.32, so ensure the inverse doesn't map device coordinates
// out of range.
const SkScalar max_dev_coord = 32767.0f;
const SkRect src = inv.mapRect(SkRect::MakeWH(max_dev_coord, max_dev_coord));
// take 1/4 of max signed 32bits so we have room to subtract local values
const SkScalar max_fixed32dot32 = float(SK_MaxS32) * 0.25f;
if (!SkRect::MakeLTRB(-max_fixed32dot32, -max_fixed32dot32,
+max_fixed32dot32, +max_fixed32dot32).contains(src)) {
return false;
}
// legacy shader impl should be able to handle these matrices
return true;
}
SkShaderBase::Context* SkImageShader::onMakeContext(const ContextRec& rec,
SkArenaAlloc* alloc) const {
SkASSERT(!needs_subset(fImage.get(), fSubset)); // TODO(skbug.com/12784)
if (fImage->alphaType() == kUnpremul_SkAlphaType) {
return nullptr;
}
if (fImage->colorType() != kN32_SkColorType) {
return nullptr;
}
if (fTileModeX != fTileModeY) {
return nullptr;
}
if (fTileModeX == SkTileMode::kDecal || fTileModeY == SkTileMode::kDecal) {
return nullptr;
}
SkSamplingOptions sampling = fSampling;
if (sampling.isAniso()) {
sampling = SkSamplingPriv::AnisoFallback(fImage->hasMipmaps());
}
auto supported = [](const SkSamplingOptions& sampling) {
const std::tuple<SkFilterMode,SkMipmapMode> supported[] = {
{SkFilterMode::kNearest, SkMipmapMode::kNone}, // legacy None
{SkFilterMode::kLinear, SkMipmapMode::kNone}, // legacy Low
{SkFilterMode::kLinear, SkMipmapMode::kNearest}, // legacy Medium
};
for (auto [f, m] : supported) {
if (sampling.filter == f && sampling.mipmap == m) {
return true;
}
}
return false;
};
if (sampling.useCubic || !supported(sampling)) {
return nullptr;
}
// SkBitmapProcShader stores bitmap coordinates in a 16bit buffer,
// so it can't handle bitmaps larger than 65535.
//
// We back off another bit to 32767 to make small amounts of
// intermediate math safe, e.g. in
//
// SkFixed fx = ...;
// fx = tile(fx + SK_Fixed1);
//
// we want to make sure (fx + SK_Fixed1) never overflows.
if (fImage-> width() > 32767 ||
fImage->height() > 32767) {
return nullptr;
}
SkMatrix inv;
if (!this->computeTotalInverse(*rec.fMatrix, rec.fLocalMatrix, &inv) ||
!legacy_shader_can_handle(inv)) {
return nullptr;
}
if (!rec.isLegacyCompatible(fImage->colorSpace())) {
return nullptr;
}
return SkBitmapProcLegacyShader::MakeContext(*this, fTileModeX, fTileModeY, sampling,
as_IB(fImage.get()), rec, alloc);
}
#endif
SkImage* SkImageShader::onIsAImage(SkMatrix* texM, SkTileMode xy[]) const {
if (texM) {
*texM = SkMatrix::I();
}
if (xy) {
xy[0] = fTileModeX;
xy[1] = fTileModeY;
}
return const_cast<SkImage*>(fImage.get());
}
sk_sp<SkShader> SkImageShader::Make(sk_sp<SkImage> image,
SkTileMode tmx, SkTileMode tmy,
const SkSamplingOptions& options,
const SkMatrix* localMatrix,
bool clampAsIfUnpremul) {
SkRect subset = image ? SkRect::Make(image->dimensions()) : SkRect::MakeEmpty();
return MakeSubset(std::move(image), subset, tmx, tmy, options, localMatrix, clampAsIfUnpremul);
}
sk_sp<SkShader> SkImageShader::MakeRaw(sk_sp<SkImage> image,
SkTileMode tmx, SkTileMode tmy,
const SkSamplingOptions& options,
const SkMatrix* localMatrix) {
if (options.useCubic) {
return nullptr;
}
if (!image) {
return SkShaders::Empty();
}
auto subset = SkRect::Make(image->dimensions());
return SkLocalMatrixShader::MakeWrapped<SkImageShader>(localMatrix,
image,
subset,
tmx, tmy,
options,
/*raw=*/true,
/*clampAsIfUnpremul=*/false);
}
sk_sp<SkShader> SkImageShader::MakeSubset(sk_sp<SkImage> image,
const SkRect& subset,
SkTileMode tmx, SkTileMode tmy,
const SkSamplingOptions& options,
const SkMatrix* localMatrix,
bool clampAsIfUnpremul) {
auto is_unit = [](float x) {
return x >= 0 && x <= 1;
};
if (options.useCubic) {
if (!is_unit(options.cubic.B) || !is_unit(options.cubic.C)) {
return nullptr;
}
}
if (!image || subset.isEmpty()) {
return SkShaders::Empty();
}
// Validate subset and check if we can drop it
if (!SkRect::Make(image->bounds()).contains(subset)) {
return nullptr;
}
// TODO(skbug.com/12784): GPU-only for now since it's only supported in onAsFragmentProcessor()
SkASSERT(!needs_subset(image.get(), subset) || image->isTextureBacked());
return SkLocalMatrixShader::MakeWrapped<SkImageShader>(localMatrix,
std::move(image),
subset,
tmx, tmy,
options,
/*raw=*/false,
clampAsIfUnpremul);
}
///////////////////////////////////////////////////////////////////////////////////////////////////
#if defined(SK_GANESH)
#include "src/gpu/ganesh/GrColorInfo.h"
#include "src/gpu/ganesh/GrFPArgs.h"
#include "src/gpu/ganesh/effects/GrBlendFragmentProcessor.h"
std::unique_ptr<GrFragmentProcessor>
SkImageShader::asFragmentProcessor(const GrFPArgs& args, const MatrixRec& mRec) const {
SkTileMode tileModes[2] = {fTileModeX, fTileModeY};
const SkRect* subset = needs_subset(fImage.get(), fSubset) ? &fSubset : nullptr;
auto fp = as_IB(fImage.get())->asFragmentProcessor(args.fContext,
fSampling,
tileModes,
SkMatrix::I(),
subset);
if (!fp) {
return nullptr;
}
bool success;
std::tie(success, fp) = mRec.apply(std::move(fp));
if (!success) {
return nullptr;
}
if (!fRaw) {
fp = GrColorSpaceXformEffect::Make(std::move(fp),
fImage->colorSpace(),
fImage->alphaType(),
args.fDstColorInfo->colorSpace(),
kPremul_SkAlphaType);
if (fImage->isAlphaOnly()) {
fp = GrBlendFragmentProcessor::Make<SkBlendMode::kDstIn>(std::move(fp), nullptr);
}
}
return fp;
}
#endif
#if defined(SK_GRAPHITE)
void SkImageShader::addToKey(const skgpu::graphite::KeyContext& keyContext,
skgpu::graphite::PaintParamsKeyBuilder* builder,
skgpu::graphite::PipelineDataGatherer* gatherer) const {
using namespace skgpu::graphite;
ImageShaderBlock::ImageData imgData(fSampling, fTileModeX, fTileModeY, fSubset,
ReadSwizzle::kRGBA);
auto [ imageToDraw, newSampling ] = skgpu::graphite::GetGraphiteBacked(keyContext.recorder(),
fImage.get(),
fSampling);
if (imageToDraw) {
imgData.fSampling = newSampling;
skgpu::Mipmapped mipmapped = (newSampling.mipmap != SkMipmapMode::kNone)
? skgpu::Mipmapped::kYes : skgpu::Mipmapped::kNo;
auto [view, _] = as_IB(imageToDraw)->asView(keyContext.recorder(), mipmapped);
imgData.fTextureProxy = view.refProxy();
skgpu::Swizzle readSwizzle = view.swizzle();
// If the color type is alpha-only, propagate the alpha value to the other channels.
if (imageToDraw->isAlphaOnly()) {
readSwizzle = skgpu::Swizzle::Concat(readSwizzle, skgpu::Swizzle("aaaa"));
}
imgData.fReadSwizzle = swizzle_class_to_read_enum(readSwizzle);
}
if (!fRaw) {
imgData.fSteps = SkColorSpaceXformSteps(fImage->colorSpace(),
fImage->alphaType(),
keyContext.dstColorInfo().colorSpace(),
keyContext.dstColorInfo().alphaType());
if (fImage->isAlphaOnly()) {
SkSpan<const float> constants = skgpu::GetPorterDuffBlendConstants(SkBlendMode::kDstIn);
// expects dst, src
PorterDuffBlendShaderBlock::BeginBlock(keyContext, builder, gatherer,
{constants});
// dst
SolidColorShaderBlock::BeginBlock(keyContext, builder, gatherer,
keyContext.paintColor());
builder->endBlock();
// src
ImageShaderBlock::BeginBlock(keyContext, builder, gatherer, &imgData);
builder->endBlock();
builder->endBlock();
return;
}
}
ImageShaderBlock::BeginBlock(keyContext, builder, gatherer, &imgData);
builder->endBlock();
}
#endif
///////////////////////////////////////////////////////////////////////////////////////////////////
#include "src/core/SkImagePriv.h"
sk_sp<SkShader> SkMakeBitmapShaderForPaint(const SkPaint& paint, const SkBitmap& src,
SkTileMode tmx, SkTileMode tmy,
const SkSamplingOptions& sampling,
const SkMatrix* localMatrix, SkCopyPixelsMode mode) {
auto s = SkImageShader::Make(SkMakeImageFromRasterBitmap(src, mode),
tmx, tmy, sampling, localMatrix);
if (!s) {
return nullptr;
}
if (SkColorTypeIsAlphaOnly(src.colorType()) && paint.getShader()) {
// Compose the image shader with the paint's shader. Alpha images+shaders should output the
// texture's alpha multiplied by the shader's color. DstIn (d*sa) will achieve this with
// the source image and dst shader (MakeBlend takes dst first, src second).
s = SkShaders::Blend(SkBlendMode::kDstIn, paint.refShader(), std::move(s));
}
return s;
}
void SkShaderBase::RegisterFlattenables() { SK_REGISTER_FLATTENABLE(SkImageShader); }
namespace {
struct MipLevelHelper {
SkPixmap pm;
SkMatrix inv;
SkRasterPipeline_GatherCtx* gather;
SkRasterPipeline_TileCtx* limitX;
SkRasterPipeline_TileCtx* limitY;
SkRasterPipeline_DecalTileCtx* decalCtx = nullptr;
void allocAndInit(SkArenaAlloc* alloc,
const SkSamplingOptions& sampling,
SkTileMode tileModeX,
SkTileMode tileModeY) {
gather = alloc->make<SkRasterPipeline_GatherCtx>();
gather->pixels = pm.addr();
gather->stride = pm.rowBytesAsPixels();
gather->width = pm.width();
gather->height = pm.height();
if (sampling.useCubic) {
SkImageShader::CubicResamplerMatrix(sampling.cubic.B, sampling.cubic.C)
.getColMajor(gather->weights);
}
limitX = alloc->make<SkRasterPipeline_TileCtx>();
limitY = alloc->make<SkRasterPipeline_TileCtx>();
limitX->scale = pm.width();
limitX->invScale = 1.0f / pm.width();
limitY->scale = pm.height();
limitY->invScale = 1.0f / pm.height();
// We would like an image that is mapped 1:1 with device pixels but at a half pixel offset
// to select every pixel from the src image once. Our rasterizer biases upward. That is a
// rect from 0.5...1.5 fills pixel 1 and not pixel 0. So we make exact integer pixel sample
// values select the pixel to the left/above the integer value.
//
// Note that a mirror mapping between canvas and image space will not have this property -
// on one side of the image a row/column will be skipped and one repeated on the other side.
//
// The GM nearest_half_pixel_image tests both of the above scenarios.
//
// The implementation of SkTileMode::kMirror also modifies integer pixel snapping to create
// consistency when the sample coords are running backwards and must account for gather
// modification we perform here. The GM mirror_tile tests this.
if (!sampling.useCubic && sampling.filter == SkFilterMode::kNearest) {
gather->roundDownAtInteger = true;
limitX->mirrorBiasDir = limitY->mirrorBiasDir = 1;
}
if (tileModeX == SkTileMode::kDecal || tileModeY == SkTileMode::kDecal) {
decalCtx = alloc->make<SkRasterPipeline_DecalTileCtx>();
decalCtx->limit_x = limitX->scale;
decalCtx->limit_y = limitY->scale;
// When integer sample coords snap left/up then we want the right/bottom edge of the
// image bounds to be inside the image rather than the left/top edge, that is (0, w]
// rather than [0, w).
if (gather->roundDownAtInteger) {
decalCtx->inclusiveEdge_x = decalCtx->limit_x;
decalCtx->inclusiveEdge_y = decalCtx->limit_y;
}
}
}
};
} // namespace
static SkSamplingOptions tweak_sampling(SkSamplingOptions sampling, const SkMatrix& matrix) {
SkFilterMode filter = sampling.filter;
// When the matrix is just an integer translate, bilerp == nearest neighbor.
if (filter == SkFilterMode::kLinear &&
matrix.getType() <= SkMatrix::kTranslate_Mask &&
matrix.getTranslateX() == (int)matrix.getTranslateX() &&
matrix.getTranslateY() == (int)matrix.getTranslateY()) {
filter = SkFilterMode::kNearest;
}
return SkSamplingOptions(filter, sampling.mipmap);
}
bool SkImageShader::appendStages(const SkStageRec& rec, const MatrixRec& mRec) const {
SkASSERT(!needs_subset(fImage.get(), fSubset)); // TODO(skbug.com/12784)
// We only support certain sampling options in stages so far
auto sampling = fSampling;
if (sampling.isAniso()) {
sampling = SkSamplingPriv::AnisoFallback(fImage->hasMipmaps());
}
SkRasterPipeline* p = rec.fPipeline;
SkArenaAlloc* alloc = rec.fAlloc;
SkMatrix baseInv;
// If the total matrix isn't valid then we will always access the base MIP level.
if (mRec.totalMatrixIsValid()) {
if (!mRec.totalInverse(&baseInv)) {
return false;
}
baseInv.normalizePerspective();
}
SkASSERT(!sampling.useCubic || sampling.mipmap == SkMipmapMode::kNone);
auto* access = SkMipmapAccessor::Make(alloc, fImage.get(), baseInv, sampling.mipmap);
if (!access) {
return false;
}
MipLevelHelper upper;
std::tie(upper.pm, upper.inv) = access->level();
if (!sampling.useCubic) {
// TODO: can tweak_sampling sometimes for cubic too when B=0
if (mRec.totalMatrixIsValid()) {
sampling = tweak_sampling(sampling, SkMatrix::Concat(upper.inv, baseInv));
}
}
if (!mRec.apply(rec, upper.inv)) {
return false;
}
upper.allocAndInit(alloc, sampling, fTileModeX, fTileModeY);
MipLevelHelper lower;
SkRasterPipeline_MipmapCtx* mipmapCtx = nullptr;
float lowerWeight = access->lowerWeight();
if (lowerWeight > 0) {
std::tie(lower.pm, lower.inv) = access->lowerLevel();
mipmapCtx = alloc->make<SkRasterPipeline_MipmapCtx>();
mipmapCtx->lowerWeight = lowerWeight;
mipmapCtx->scaleX = static_cast<float>(lower.pm.width()) / upper.pm.width();
mipmapCtx->scaleY = static_cast<float>(lower.pm.height()) / upper.pm.height();
lower.allocAndInit(alloc, sampling, fTileModeX, fTileModeY);
p->append(SkRasterPipelineOp::mipmap_linear_init, mipmapCtx);
}
const bool decalBothAxes = fTileModeX == SkTileMode::kDecal && fTileModeY == SkTileMode::kDecal;
auto append_tiling_and_gather = [&](const MipLevelHelper* level) {
if (decalBothAxes) {
p->append(SkRasterPipelineOp::decal_x_and_y, level->decalCtx);
} else {
switch (fTileModeX) {
case SkTileMode::kClamp: /* The gather_xxx stage will clamp for us. */
break;
case SkTileMode::kMirror:
p->append(SkRasterPipelineOp::mirror_x, level->limitX);
break;
case SkTileMode::kRepeat:
p->append(SkRasterPipelineOp::repeat_x, level->limitX);
break;
case SkTileMode::kDecal:
p->append(SkRasterPipelineOp::decal_x, level->decalCtx);
break;
}
switch (fTileModeY) {
case SkTileMode::kClamp: /* The gather_xxx stage will clamp for us. */
break;
case SkTileMode::kMirror:
p->append(SkRasterPipelineOp::mirror_y, level->limitY);
break;
case SkTileMode::kRepeat:
p->append(SkRasterPipelineOp::repeat_y, level->limitY);
break;
case SkTileMode::kDecal:
p->append(SkRasterPipelineOp::decal_y, level->decalCtx);
break;
}
}
void* ctx = level->gather;
switch (level->pm.colorType()) {
case kAlpha_8_SkColorType: p->append(SkRasterPipelineOp::gather_a8, ctx); break;
case kA16_unorm_SkColorType: p->append(SkRasterPipelineOp::gather_a16, ctx); break;
case kA16_float_SkColorType: p->append(SkRasterPipelineOp::gather_af16, ctx); break;
case kRGB_565_SkColorType: p->append(SkRasterPipelineOp::gather_565, ctx); break;
case kARGB_4444_SkColorType: p->append(SkRasterPipelineOp::gather_4444, ctx); break;
case kR8G8_unorm_SkColorType: p->append(SkRasterPipelineOp::gather_rg88, ctx); break;
case kR16G16_unorm_SkColorType: p->append(SkRasterPipelineOp::gather_rg1616,ctx); break;
case kR16G16_float_SkColorType: p->append(SkRasterPipelineOp::gather_rgf16, ctx); break;
case kRGBA_8888_SkColorType: p->append(SkRasterPipelineOp::gather_8888, ctx); break;
case kRGBA_1010102_SkColorType:
p->append(SkRasterPipelineOp::gather_1010102, ctx);
break;
case kR16G16B16A16_unorm_SkColorType:
p->append(SkRasterPipelineOp::gather_16161616, ctx);
break;
case kRGBA_F16Norm_SkColorType:
case kRGBA_F16_SkColorType: p->append(SkRasterPipelineOp::gather_f16, ctx); break;
case kRGBA_F32_SkColorType: p->append(SkRasterPipelineOp::gather_f32, ctx); break;
case kGray_8_SkColorType: p->append(SkRasterPipelineOp::gather_a8, ctx);
p->append(SkRasterPipelineOp::alpha_to_gray ); break;
case kR8_unorm_SkColorType: p->append(SkRasterPipelineOp::gather_a8, ctx);
p->append(SkRasterPipelineOp::alpha_to_red ); break;
case kRGB_888x_SkColorType: p->append(SkRasterPipelineOp::gather_8888, ctx);
p->append(SkRasterPipelineOp::force_opaque ); break;
case kBGRA_1010102_SkColorType:
p->append(SkRasterPipelineOp::gather_1010102, ctx);
p->append(SkRasterPipelineOp::swap_rb);
break;
case kRGB_101010x_SkColorType:
p->append(SkRasterPipelineOp::gather_1010102, ctx);
p->append(SkRasterPipelineOp::force_opaque);
break;
case kBGR_101010x_XR_SkColorType:
SkASSERT(false);
break;
case kBGR_101010x_SkColorType:
p->append(SkRasterPipelineOp::gather_1010102, ctx);
p->append(SkRasterPipelineOp::force_opaque);
p->append(SkRasterPipelineOp::swap_rb);
break;
case kBGRA_8888_SkColorType:
p->append(SkRasterPipelineOp::gather_8888, ctx);
p->append(SkRasterPipelineOp::swap_rb);
break;
case kSRGBA_8888_SkColorType:
p->append(SkRasterPipelineOp::gather_8888, ctx);
p->append_transfer_function(*skcms_sRGB_TransferFunction());
break;
case kUnknown_SkColorType: SkASSERT(false);
}
if (level->decalCtx) {
p->append(SkRasterPipelineOp::check_decal_mask, level->decalCtx);
}
};
auto append_misc = [&] {
SkColorSpace* cs = upper.pm.colorSpace();
SkAlphaType at = upper.pm.alphaType();
// Color for alpha-only images comes from the paint (already converted to dst color space).
if (SkColorTypeIsAlphaOnly(upper.pm.colorType()) && !fRaw) {
p->append_set_rgb(alloc, rec.fPaintColor);
cs = rec.fDstCS;
at = kUnpremul_SkAlphaType;
}
// Bicubic filtering naturally produces out of range values on both sides of [0,1].
if (sampling.useCubic) {
p->append(at == kUnpremul_SkAlphaType || fClampAsIfUnpremul
? SkRasterPipelineOp::clamp_01
: SkRasterPipelineOp::clamp_gamut);
}
// Transform color space and alpha type to match shader convention (dst CS, premul alpha).
if (!fRaw) {
alloc->make<SkColorSpaceXformSteps>(cs, at, rec.fDstCS, kPremul_SkAlphaType)->apply(p);
}
return true;
};
// Check for fast-path stages.
// TODO: Could we use the fast-path stages for each level when doing linear mipmap filtering?
SkColorType ct = upper.pm.colorType();
if (true
&& (ct == kRGBA_8888_SkColorType || ct == kBGRA_8888_SkColorType)
&& !sampling.useCubic && sampling.filter == SkFilterMode::kLinear
&& sampling.mipmap != SkMipmapMode::kLinear
&& fTileModeX == SkTileMode::kClamp && fTileModeY == SkTileMode::kClamp) {
p->append(SkRasterPipelineOp::bilerp_clamp_8888, upper.gather);
if (ct == kBGRA_8888_SkColorType) {
p->append(SkRasterPipelineOp::swap_rb);
}
return append_misc();
}
if (true
&& (ct == kRGBA_8888_SkColorType || ct == kBGRA_8888_SkColorType)
&& sampling.useCubic
&& fTileModeX == SkTileMode::kClamp && fTileModeY == SkTileMode::kClamp) {
p->append(SkRasterPipelineOp::bicubic_clamp_8888, upper.gather);
if (ct == kBGRA_8888_SkColorType) {
p->append(SkRasterPipelineOp::swap_rb);
}
return append_misc();
}
// This context can be shared by both levels when doing linear mipmap filtering
SkRasterPipeline_SamplerCtx* sampler = alloc->make<SkRasterPipeline_SamplerCtx>();
auto sample = [&](SkRasterPipelineOp setup_x,
SkRasterPipelineOp setup_y,
const MipLevelHelper* level) {
p->append(setup_x, sampler);
p->append(setup_y, sampler);
append_tiling_and_gather(level);
p->append(SkRasterPipelineOp::accumulate, sampler);
};
auto sample_level = [&](const MipLevelHelper* level) {
if (sampling.useCubic) {
CubicResamplerMatrix(sampling.cubic.B, sampling.cubic.C).getColMajor(sampler->weights);
p->append(SkRasterPipelineOp::bicubic_setup, sampler);
sample(SkRasterPipelineOp::bicubic_n3x, SkRasterPipelineOp::bicubic_n3y, level);
sample(SkRasterPipelineOp::bicubic_n1x, SkRasterPipelineOp::bicubic_n3y, level);
sample(SkRasterPipelineOp::bicubic_p1x, SkRasterPipelineOp::bicubic_n3y, level);
sample(SkRasterPipelineOp::bicubic_p3x, SkRasterPipelineOp::bicubic_n3y, level);
sample(SkRasterPipelineOp::bicubic_n3x, SkRasterPipelineOp::bicubic_n1y, level);
sample(SkRasterPipelineOp::bicubic_n1x, SkRasterPipelineOp::bicubic_n1y, level);
sample(SkRasterPipelineOp::bicubic_p1x, SkRasterPipelineOp::bicubic_n1y, level);
sample(SkRasterPipelineOp::bicubic_p3x, SkRasterPipelineOp::bicubic_n1y, level);
sample(SkRasterPipelineOp::bicubic_n3x, SkRasterPipelineOp::bicubic_p1y, level);
sample(SkRasterPipelineOp::bicubic_n1x, SkRasterPipelineOp::bicubic_p1y, level);
sample(SkRasterPipelineOp::bicubic_p1x, SkRasterPipelineOp::bicubic_p1y, level);
sample(SkRasterPipelineOp::bicubic_p3x, SkRasterPipelineOp::bicubic_p1y, level);
sample(SkRasterPipelineOp::bicubic_n3x, SkRasterPipelineOp::bicubic_p3y, level);
sample(SkRasterPipelineOp::bicubic_n1x, SkRasterPipelineOp::bicubic_p3y, level);
sample(SkRasterPipelineOp::bicubic_p1x, SkRasterPipelineOp::bicubic_p3y, level);
sample(SkRasterPipelineOp::bicubic_p3x, SkRasterPipelineOp::bicubic_p3y, level);
p->append(SkRasterPipelineOp::move_dst_src);
} else if (sampling.filter == SkFilterMode::kLinear) {
p->append(SkRasterPipelineOp::bilinear_setup, sampler);
sample(SkRasterPipelineOp::bilinear_nx, SkRasterPipelineOp::bilinear_ny, level);
sample(SkRasterPipelineOp::bilinear_px, SkRasterPipelineOp::bilinear_ny, level);
sample(SkRasterPipelineOp::bilinear_nx, SkRasterPipelineOp::bilinear_py, level);
sample(SkRasterPipelineOp::bilinear_px, SkRasterPipelineOp::bilinear_py, level);
p->append(SkRasterPipelineOp::move_dst_src);
} else {
append_tiling_and_gather(level);
}
};
sample_level(&upper);
if (mipmapCtx) {
p->append(SkRasterPipelineOp::mipmap_linear_update, mipmapCtx);
sample_level(&lower);
p->append(SkRasterPipelineOp::mipmap_linear_finish, mipmapCtx);
}
return append_misc();
}
skvm::Color SkImageShader::program(skvm::Builder* p,
skvm::Coord device,
skvm::Coord origLocal,
skvm::Color paint,
const MatrixRec& mRec,
const SkColorInfo& dst,
skvm::Uniforms* uniforms,
SkArenaAlloc* alloc) const {
SkASSERT(!needs_subset(fImage.get(), fSubset)); // TODO(skbug.com/12784)
auto sampling = fSampling;
if (sampling.isAniso()) {
sampling = SkSamplingPriv::AnisoFallback(fImage->hasMipmaps());
}
SkMatrix baseInv;
// If the total matrix isn't valid then we will always access the base MIP level.
if (mRec.totalMatrixIsValid()) {
if (!mRec.totalInverse(&baseInv)) {
return {};
}
baseInv.normalizePerspective();
}
SkASSERT(!sampling.useCubic || sampling.mipmap == SkMipmapMode::kNone);
auto* access = SkMipmapAccessor::Make(alloc, fImage.get(), baseInv, sampling.mipmap);
if (!access) {
return {};
}
SkPixmap upper;
SkMatrix upperInv;
std::tie(upper, upperInv) = access->level();
if (!sampling.useCubic) {
// TODO: can tweak_sampling sometimes for cubic too when B=0
if (mRec.totalMatrixIsValid()) {
sampling = tweak_sampling(sampling, SkMatrix::Concat(upperInv, baseInv));
}
}
SkPixmap lowerPixmap;
SkMatrix lowerInv;
SkPixmap* lower = nullptr;
float lowerWeight = access->lowerWeight();
if (lowerWeight > 0) {
std::tie(lowerPixmap, lowerInv) = access->lowerLevel();
lower = &lowerPixmap;
}
skvm::Coord upperLocal = origLocal;
if (!mRec.apply(p, &upperLocal, uniforms, upperInv).has_value()) {
return {};
}
// We can exploit image opacity to skip work unpacking alpha channels.
const bool input_is_opaque = SkAlphaTypeIsOpaque(upper.alphaType())
|| SkColorTypeIsAlwaysOpaque(upper.colorType());
// Each call to sample() will try to rewrite the same uniforms over and over,
// so remember where we start and reset back there each time. That way each
// sample() call uses the same uniform offsets.
auto compute_clamp_limit = [&](float limit) {
// Subtract an ulp so the upper clamp limit excludes limit itself.
int bits;
memcpy(&bits, &limit, 4);
return p->uniformF(uniforms->push(bits-1));
};
// Except in the simplest case (no mips, no filtering), we reference uniforms
// more than once. To avoid adding/registering them multiple times, we pre-load them
// into a struct (just to logically group them together), based on the "current"
// pixmap (level of a mipmap).
//
struct Uniforms {
skvm::F32 w, iw, i2w,
h, ih, i2h;
skvm::F32 clamp_w,
clamp_h;
skvm::Uniform addr;
skvm::I32 rowBytesAsPixels;
skvm::PixelFormat pixelFormat; // not a uniform, but needed for each texel sample,
// so we store it here, since it is also dependent on
// the current pixmap (level).
};
auto setup_uniforms = [&](const SkPixmap& pm) -> Uniforms {
skvm::PixelFormat pixelFormat = skvm::SkColorType_to_PixelFormat(pm.colorType());
return {
p->uniformF(uniforms->pushF( pm.width())),
p->uniformF(uniforms->pushF(1.0f/pm.width())), // iff tileX == kRepeat
p->uniformF(uniforms->pushF(0.5f/pm.width())), // iff tileX == kMirror
p->uniformF(uniforms->pushF( pm.height())),
p->uniformF(uniforms->pushF(1.0f/pm.height())), // iff tileY == kRepeat
p->uniformF(uniforms->pushF(0.5f/pm.height())), // iff tileY == kMirror
compute_clamp_limit(pm. width()),
compute_clamp_limit(pm.height()),
uniforms->pushPtr(pm.addr()),
p->uniform32(uniforms->push(pm.rowBytesAsPixels())),
pixelFormat,
};
};
auto sample_texel = [&](const Uniforms& u, skvm::F32 sx, skvm::F32 sy) -> skvm::Color {
// repeat() and mirror() are written assuming they'll be followed by a [0,scale) clamp.
auto repeat = [&](skvm::F32 v, skvm::F32 S, skvm::F32 I) {
return v - floor(v * I) * S;
};
auto mirror = [&](skvm::F32 v, skvm::F32 S, skvm::F32 I2) {
// abs( (v-scale) - (2*scale)*floor((v-scale)*(0.5f/scale)) - scale )
// {---A---} {------------------B------------------}
skvm::F32 A = v - S,
B = (S + S) * floor(A * I2);
return abs(A - B - S);
};
switch (fTileModeX) {
case SkTileMode::kDecal: /* handled after gather */ break;
case SkTileMode::kClamp: /* we always clamp */ break;
case SkTileMode::kRepeat: sx = repeat(sx, u.w, u.iw); break;
case SkTileMode::kMirror: sx = mirror(sx, u.w, u.i2w); break;
}
switch (fTileModeY) {
case SkTileMode::kDecal: /* handled after gather */ break;
case SkTileMode::kClamp: /* we always clamp */ break;
case SkTileMode::kRepeat: sy = repeat(sy, u.h, u.ih); break;
case SkTileMode::kMirror: sy = mirror(sy, u.h, u.i2h); break;
}
// Always clamp sample coordinates to [0,width), [0,height), both for memory
// safety and to handle the clamps still needed by kClamp, kRepeat, and kMirror.
skvm::F32 clamped_x = clamp(sx, 0, u.clamp_w),
clamped_y = clamp(sy, 0, u.clamp_h);
// Load pixels from pm.addr()[(int)sx + (int)sy*stride].
skvm::I32 index = trunc(clamped_x) +
trunc(clamped_y) * u.rowBytesAsPixels;
skvm::Color c = gather(u.pixelFormat, u.addr, index);
// If we know the image is opaque, jump right to alpha = 1.0f, skipping work to unpack it.
if (input_is_opaque) {
c.a = p->splat(1.0f);
}
// Mask away any pixels that we tried to sample outside the bounds in kDecal.
if (fTileModeX == SkTileMode::kDecal || fTileModeY == SkTileMode::kDecal) {
skvm::I32 mask = p->splat(~0);
if (fTileModeX == SkTileMode::kDecal) { mask &= (sx == clamped_x); }
if (fTileModeY == SkTileMode::kDecal) { mask &= (sy == clamped_y); }
c.r = pun_to_F32(p->bit_and(mask, pun_to_I32(c.r)));
c.g = pun_to_F32(p->bit_and(mask, pun_to_I32(c.g)));
c.b = pun_to_F32(p->bit_and(mask, pun_to_I32(c.b)));
c.a = pun_to_F32(p->bit_and(mask, pun_to_I32(c.a)));
// Notice that even if input_is_opaque, c.a might now be 0.
}
return c;
};
auto sample_level = [&](const SkPixmap& pm, skvm::Coord local) {
const Uniforms u = setup_uniforms(pm);
if (sampling.useCubic) {
// All bicubic samples have the same fractional offset (fx,fy) from the center.
// They're either the 16 corners of a 3x3 grid/ surrounding (x,y) at (0.5,0.5) off-center.
skvm::F32 fx = fract(local.x + 0.5f),
fy = fract(local.y + 0.5f);
skvm::F32 wx[4],
wy[4];
SkM44 weights = CubicResamplerMatrix(sampling.cubic.B, sampling.cubic.C);
auto dot = [](const skvm::F32 a[], const skvm::F32 b[]) {
return a[0]*b[0] + a[1]*b[1] + a[2]*b[2] + a[3]*b[3];
};
const skvm::F32 tmpx[] = { p->splat(1.0f), fx, fx*fx, fx*fx*fx };
const skvm::F32 tmpy[] = { p->splat(1.0f), fy, fy*fy, fy*fy*fy };
for (int row = 0; row < 4; ++row) {
SkV4 r = weights.row(row);
skvm::F32 ru[] = {
p->uniformF(uniforms->pushF(r[0])),
p->uniformF(uniforms->pushF(r[1])),
p->uniformF(uniforms->pushF(r[2])),
p->uniformF(uniforms->pushF(r[3])),
};
wx[row] = dot(ru, tmpx);
wy[row] = dot(ru, tmpy);
}
skvm::Color c;
c.r = c.g = c.b = c.a = p->splat(0.0f);
skvm::F32 sy = local.y - 1.5f;
for (int j = 0; j < 4; j++, sy += 1.0f) {
skvm::F32 sx = local.x - 1.5f;
for (int i = 0; i < 4; i++, sx += 1.0f) {
skvm::Color s = sample_texel(u, sx,sy);
skvm::F32 w = wx[i] * wy[j];
c.r += s.r * w;
c.g += s.g * w;
c.b += s.b * w;
c.a += s.a * w;
}
}
return c;
} else if (sampling.filter == SkFilterMode::kLinear) {
// Our four sample points are the corners of a logical 1x1 pixel
// box surrounding (x,y) at (0.5,0.5) off-center.
skvm::F32 left = local.x - 0.5f,
top = local.y - 0.5f,
right = local.x + 0.5f,
bottom = local.y + 0.5f;
// The fractional parts of right and bottom are our lerp factors in x and y respectively.
skvm::F32 fx = fract(right ),
fy = fract(bottom);
return lerp(lerp(sample_texel(u, left,top ), sample_texel(u, right,top ), fx),
lerp(sample_texel(u, left,bottom), sample_texel(u, right,bottom), fx), fy);
} else {
SkASSERT(sampling.filter == SkFilterMode::kNearest);
// Our rasterizer biases upward. That is a rect from 0.5...1.5 fills pixel 1 and not
// pixel 0. To make an image that is mapped 1:1 with device pixels but at a half pixel
// offset select every pixel from the src image once we make exact integer pixel sample
// values round down not up. Note that a mirror mapping will not have this property.
local.x = skvm::pun_to_F32(skvm::pun_to_I32(local.x) - 1);
local.y = skvm::pun_to_F32(skvm::pun_to_I32(local.y) - 1);
return sample_texel(u, local.x,local.y);
}
};
skvm::Color c = sample_level(upper, upperLocal);
if (lower) {
skvm::Coord lowerLocal = origLocal;
if (!mRec.apply(p, &lowerLocal, uniforms, lowerInv)) {
return {};
}
// lower * weight + upper * (1 - weight)
c = lerp(c,
sample_level(*lower, lowerLocal),
p->uniformF(uniforms->pushF(lowerWeight)));
}
// If the input is opaque and we're not in decal mode, that means the output is too.
// Forcing *a to 1.0 here will retroactively skip any work we did to interpolate sample alphas.
if (input_is_opaque
&& fTileModeX != SkTileMode::kDecal
&& fTileModeY != SkTileMode::kDecal) {
c.a = p->splat(1.0f);
}
// Alpha-only images get their color from the paint (already converted to dst color space).
SkColorSpace* cs = upper.colorSpace();
SkAlphaType at = upper.alphaType();
if (SkColorTypeIsAlphaOnly(upper.colorType()) && !fRaw) {
c.r = paint.r;
c.g = paint.g;
c.b = paint.b;
cs = dst.colorSpace();
at = kUnpremul_SkAlphaType;
}
if (sampling.useCubic) {
// Bicubic filtering naturally produces out of range values on both sides of [0,1].
c.a = clamp01(c.a);
skvm::F32 limit = (at == kUnpremul_SkAlphaType || fClampAsIfUnpremul)
? p->splat(1.0f)
: c.a;
c.r = clamp(c.r, 0.0f, limit);
c.g = clamp(c.g, 0.0f, limit);
c.b = clamp(c.b, 0.0f, limit);
}
return fRaw ? c
: SkColorSpaceXformSteps{cs, at, dst.colorSpace(), dst.alphaType()}.program(
p, uniforms, c);
}