skia2/gm/sample_matrix_variable.cpp
Ethan Nicholas 5843012837 Add sample(child, matrix) to SkSL.
This allows fragment processors to sample their children with their
local coordinate system transformed by a matrix.

Change-Id: Ifa848bbd85b939bbc5751fec5cf8f89ee904bf39
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/282590
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
2020-04-14 16:07:34 +00:00

101 lines
4.0 KiB
C++

/*
* Copyright 2019 Google LLC.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm/gm.h"
#include "include/effects/SkGradientShader.h"
#include "src/gpu/GrBitmapTextureMaker.h"
#include "src/gpu/GrClip.h"
#include "src/gpu/GrContextPriv.h"
#include "src/gpu/GrRenderTargetContextPriv.h"
#include "src/gpu/glsl/GrGLSLFragmentShaderBuilder.h"
#include "src/gpu/ops/GrFillRectOp.h"
#include "tools/Resources.h"
class SampleMatrixVariableEffect : public GrFragmentProcessor {
public:
static constexpr GrProcessor::ClassID CLASS_ID = (GrProcessor::ClassID) 2;
SampleMatrixVariableEffect(std::unique_ptr<GrFragmentProcessor> child)
: INHERITED(CLASS_ID, kNone_OptimizationFlags) {
child->setSampleMatrix(SkSL::SampleMatrix(SkSL::SampleMatrix::Kind::kVariable));
this->registerChildProcessor(std::move(child));
}
const char* name() const override { return "SampleMatrixVariableEffect"; }
std::unique_ptr<GrFragmentProcessor> clone() const override {
SkASSERT(false);
return nullptr;
}
void onGetGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder*) const override {
}
bool onIsEqual(const GrFragmentProcessor& that) const override {
return this == &that;
}
private:
GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
typedef GrFragmentProcessor INHERITED;
};
class GLSLSampleMatrixVariableEffect : public GrGLSLFragmentProcessor {
void emitCode(EmitArgs& args) override {
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
SkString sample1 = this->invokeChildWithMatrix(0, args, "float3x3(1)");
SkString sample2 = this->invokeChildWithMatrix(0, args, "float3x3(1, -1, 0, 1, 0, 0, "
"-0.5, 1, 1)");
fragBuilder->codeAppendf("%s = (%s + %s) / 2;\n", args.fOutputColor, sample1.c_str(),
sample2.c_str());
}
};
GrGLSLFragmentProcessor* SampleMatrixVariableEffect::onCreateGLSLInstance() const {
return new GLSLSampleMatrixVariableEffect();
}
DEF_SIMPLE_GPU_GM(sample_matrix_variable, ctx, rtCtx, canvas, 512, 256) {
{
SkRect bounds = SkRect::MakeIWH(256, 256);
SkBitmap bmp;
GetResourceAsBitmap("images/mandrill_256.png", &bmp);
GrBitmapTextureMaker maker(ctx, bmp, GrImageTexGenPolicy::kDraw);
auto view = maker.view(GrMipMapped::kNo);
std::unique_ptr<GrFragmentProcessor> imgFP =
GrTextureEffect::Make(std::move(view), bmp.alphaType(), SkMatrix());
imgFP->setSampleMatrix(SkSL::SampleMatrix::Kind::kVariable);
auto fp = std::unique_ptr<GrFragmentProcessor>(
new SampleMatrixVariableEffect(std::move(imgFP)));
GrPaint paint;
paint.addCoverageFragmentProcessor(std::move(fp));
rtCtx->drawRect(GrNoClip(), std::move(paint), GrAA::kNo, SkMatrix::I(), bounds);
}
{
GrPaint paint;
SkRect bounds = SkRect::MakeLTRB(256, 0, 512, 256);
static constexpr SkColor colors[] = { 0xff00ff00, 0xffff00ff };
static constexpr SkScalar pos[] = { 0.0f, 1.0f };
const SkPoint pts[] = {{ 256, 0 }, { 512, 0 }};
auto shader = SkGradientShader::MakeLinear(pts, colors, pos,
SK_ARRAY_COUNT(colors),
SkTileMode::kRepeat);
SkMatrix matrix;
GrColorInfo colorInfo;
GrFPArgs args(ctx, &matrix, kHigh_SkFilterQuality, &colorInfo);
std::unique_ptr<GrFragmentProcessor> gradientFP = as_SB(shader)->asFragmentProcessor(args);
gradientFP->setSampleMatrix(SkSL::SampleMatrix::Kind::kVariable);
auto fp = std::unique_ptr<GrFragmentProcessor>(
new SampleMatrixVariableEffect(std::move(gradientFP)));
paint.addCoverageFragmentProcessor(std::move(fp));
rtCtx->drawRect(GrNoClip(), std::move(paint), GrAA::kNo, SkMatrix::I(), bounds);
}
}