blob: 32e908f22999dae4dbd2ad5e738cea6df3066fa5 [file] [log] [blame]
/*
* Copyright 2012 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/gradients/SkLinearGradient.h"
#include "src/core/SkKeyHelpers.h"
#include "src/core/SkReadBuffer.h"
#include "src/core/SkWriteBuffer.h"
#include "src/shaders/gradients/Sk4fLinearGradient.h"
static SkMatrix pts_to_unit_matrix(const SkPoint pts[2]) {
SkVector vec = pts[1] - pts[0];
SkScalar mag = vec.length();
SkScalar inv = mag ? SkScalarInvert(mag) : 0;
vec.scale(inv);
SkMatrix matrix;
matrix.setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY);
matrix.postTranslate(-pts[0].fX, -pts[0].fY);
matrix.postScale(inv, inv);
return matrix;
}
///////////////////////////////////////////////////////////////////////////////
SkLinearGradient::SkLinearGradient(const SkPoint pts[2], const Descriptor& desc)
: SkGradientShaderBase(desc, pts_to_unit_matrix(pts))
, fStart(pts[0])
, fEnd(pts[1]) {
}
sk_sp<SkFlattenable> SkLinearGradient::CreateProc(SkReadBuffer& buffer) {
DescriptorScope desc;
if (!desc.unflatten(buffer)) {
return nullptr;
}
SkPoint pts[2];
pts[0] = buffer.readPoint();
pts[1] = buffer.readPoint();
return SkGradientShader::MakeLinear(pts, desc.fColors, std::move(desc.fColorSpace), desc.fPos,
desc.fCount, desc.fTileMode, desc.fGradFlags,
desc.fLocalMatrix);
}
void SkLinearGradient::flatten(SkWriteBuffer& buffer) const {
this->INHERITED::flatten(buffer);
buffer.writePoint(fStart);
buffer.writePoint(fEnd);
}
#ifdef SK_ENABLE_LEGACY_SHADERCONTEXT
SkShaderBase::Context* SkLinearGradient::onMakeContext(
const ContextRec& rec, SkArenaAlloc* alloc) const
{
// make sure our colorspaces are compatible with legacy blits
if (!rec.isLegacyCompatible(fColorSpace.get())) {
return nullptr;
}
// Can't use legacy blit if we can't represent our colors as SkColors
if (!this->colorsCanConvertToSkColor()) {
return nullptr;
}
return fTileMode != SkTileMode::kDecal
? CheckedMakeContext<LinearGradient4fContext>(alloc, *this, rec)
: nullptr;
}
#endif
void SkLinearGradient::appendGradientStages(SkArenaAlloc*, SkRasterPipeline*,
SkRasterPipeline*) const {
// No extra stage needed for linear gradients.
}
skvm::F32 SkLinearGradient::transformT(skvm::Builder* p, skvm::Uniforms*,
skvm::Coord coord, skvm::I32* mask) const {
// We've baked getting t in x into the matrix, so this is pretty trivial.
return coord.x;
}
SkShader::GradientType SkLinearGradient::asAGradient(GradientInfo* info) const {
if (info) {
commonAsAGradient(info);
info->fPoint[0] = fStart;
info->fPoint[1] = fEnd;
}
return kLinear_GradientType;
}
/////////////////////////////////////////////////////////////////////
#if SK_SUPPORT_GPU
#include "src/gpu/gradients/GrGradientShader.h"
std::unique_ptr<GrFragmentProcessor> SkLinearGradient::asFragmentProcessor(
const GrFPArgs& args) const {
return GrGradientShader::MakeLinear(*this, args);
}
#endif
void SkLinearGradient::addToKey(SkShaderCodeDictionary* dict,
SkBackend backend,
SkPaintParamsKeyBuilder* builder,
SkUniformBlock* uniformBlock) const {
GradientShaderBlocks::GradientData data(kLinear_GradientType,
fStart, fEnd,
0.0f, 0.0f,
fTileMode,
fColorCount,
fOrigColors4f,
fOrigPos);
GradientShaderBlocks::AddToKey(dict, backend, builder, uniformBlock, data);
}