skia2/gm/clockwise.cpp

195 lines
8.0 KiB
C++
Raw Normal View History

/*
* Copyright 2018 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "gm.h"
#include "GrClip.h"
#include "GrContext.h"
#include "GrGpuCommandBuffer.h"
#include "GrMemoryPool.h"
#include "GrOpFlushState.h"
#include "GrRenderTargetContext.h"
#include "GrRenderTargetContextPriv.h"
#include "GrRenderTarget.h"
#include "glsl/GrGLSLFragmentShaderBuilder.h"
#include "glsl/GrGLSLGeometryProcessor.h"
#include "glsl/GrGLSLVarying.h"
#include "glsl/GrGLSLVertexGeoBuilder.h"
namespace skiagm {
static constexpr GrGeometryProcessor::Attribute gVertex =
{"vertex", kFloat2_GrVertexAttribType, kFloat2_GrSLType};
/**
* This is a GPU-backend specific test. It ensures that SkSL properly identifies clockwise-winding
* triangles (sk_Clockwise), in terms of to Skia device space, in all backends and with all render
* target origins. We draw clockwise triangles green and counter-clockwise red.
*/
class ClockwiseGM : public GM {
private:
SkString onShortName() final { return SkString("clockwise"); }
SkISize onISize() override { return SkISize::Make(300, 200); }
void onDraw(SkCanvas*) override;
};
////////////////////////////////////////////////////////////////////////////////////////////////////
// SkSL code.
class ClockwiseTestProcessor : public GrGeometryProcessor {
public:
ClockwiseTestProcessor(bool readSkFragCoord)
: GrGeometryProcessor(kClockwiseTestProcessor_ClassID)
, fReadSkFragCoord(readSkFragCoord) {
this->setVertexAttributeCnt(1);
}
const char* name() const override { return "ClockwiseTestProcessor"; }
void getGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder* b) const final {
b->add32(fReadSkFragCoord);
}
GrGLSLPrimitiveProcessor* createGLSLInstance(const GrShaderCaps&) const final;
private:
const Attribute& onVertexAttribute(int i) const override { return gVertex; }
const bool fReadSkFragCoord;
friend class GLSLClockwiseTestProcessor;
};
class GLSLClockwiseTestProcessor : public GrGLSLGeometryProcessor {
void setData(const GrGLSLProgramDataManager& pdman, const GrPrimitiveProcessor&,
FPCoordTransformIter&& transformIter) override {}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const ClockwiseTestProcessor& proc = args.fGP.cast<ClockwiseTestProcessor>();
args.fVaryingHandler->emitAttributes(proc);
gpArgs->fPositionVar.set(kFloat2_GrSLType, "vertex");
args.fFragBuilder->codeAppendf(
"%s = sk_Clockwise ? half4(0,1,0,1) : half4(1,0,0,1);", args.fOutputColor);
if (!proc.fReadSkFragCoord) {
args.fFragBuilder->codeAppendf("%s = half4(1);", args.fOutputCoverage);
} else {
// Verify layout(origin_upper_left) on gl_FragCoord does not affect gl_FrontFacing.
args.fFragBuilder->codeAppendf("%s = half4(min(sk_FragCoord.y, 1));",
args.fOutputCoverage);
}
}
};
GrGLSLPrimitiveProcessor* ClockwiseTestProcessor::createGLSLInstance(
const GrShaderCaps&) const {
return new GLSLClockwiseTestProcessor;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
// Draw Op.
class ClockwiseTestOp : public GrDrawOp {
public:
DEFINE_OP_CLASS_ID
static std::unique_ptr<GrDrawOp> Make(GrContext* context, bool readSkFragCoord, int y = 0) {
GrOpMemoryPool* pool = context->contextPriv().opMemoryPool();
return pool->allocate<ClockwiseTestOp>(readSkFragCoord, y);
}
private:
ClockwiseTestOp(bool readSkFragCoord, float y)
: GrDrawOp(ClassID()), fReadSkFragCoord(readSkFragCoord), fY(y) {
this->setBounds(SkRect::MakeIWH(300, 100), HasAABloat::kNo, IsZeroArea::kNo);
}
const char* name() const override { return "ClockwiseTestOp"; }
FixedFunctionFlags fixedFunctionFlags() const override { return FixedFunctionFlags::kNone; }
RequiresDstTexture finalize(const GrCaps&, const GrAppliedClip*) override {
return RequiresDstTexture::kNo;
}
void onPrepare(GrOpFlushState*) override {}
void onExecute(GrOpFlushState* flushState) override {
SkPoint vertices[4] = {
{100, fY},
{0, fY+100},
{0, fY},
{100, fY+100},
};
sk_sp<GrBuffer> vertexBuffer(flushState->resourceProvider()->createBuffer(
sizeof(vertices), kVertex_GrBufferType, kStatic_GrAccessPattern,
GrResourceProvider::Flags::kNone, vertices));
if (!vertexBuffer) {
return;
}
GrPipeline pipeline(flushState->drawOpArgs().fProxy, GrScissorTest::kDisabled,
SkBlendMode::kPlus);
GrMesh mesh(GrPrimitiveType::kTriangleStrip);
mesh.setNonIndexedNonInstanced(4);
mesh.setVertexData(vertexBuffer.get());
flushState->rtCommandBuffer()->draw(ClockwiseTestProcessor(fReadSkFragCoord), pipeline,
nullptr, nullptr, &mesh, 1, SkRect::MakeIWH(100, 100));
}
const bool fReadSkFragCoord;
const float fY;
friend class ::GrOpMemoryPool; // for ctor
};
////////////////////////////////////////////////////////////////////////////////////////////////////
// Test.
void ClockwiseGM::onDraw(SkCanvas* canvas) {
GrContext* ctx = canvas->getGrContext();
GrRenderTargetContext* rtc = canvas->internal_private_accessTopLayerRenderTargetContext();
if (!ctx || !rtc) {
DrawGpuOnlyMessage(canvas);
return;
}
rtc->clear(nullptr, GrColorPackRGBA(0,0,0,255),
GrRenderTargetContext::CanClearFullscreen::kYes);
// Draw the test directly to the frame buffer.
rtc->priv().testingOnly_addDrawOp(ClockwiseTestOp::Make(ctx, false, 0));
rtc->priv().testingOnly_addDrawOp(ClockwiseTestOp::Make(ctx, true, 100));
// Draw the test to an off-screen, top-down render target.
if (auto topLeftRTC = ctx->contextPriv().makeDeferredRenderTargetContext(
SkBackingFit::kExact, 100, 200, rtc->asSurfaceProxy()->config(),
nullptr, 1, GrMipMapped::kNo, kTopLeft_GrSurfaceOrigin, nullptr,
SkBudgeted::kYes)) {
topLeftRTC->clear(nullptr, 0, GrRenderTargetContext::CanClearFullscreen::kYes);
topLeftRTC->priv().testingOnly_addDrawOp(ClockwiseTestOp::Make(ctx, false, 0));
topLeftRTC->priv().testingOnly_addDrawOp(ClockwiseTestOp::Make(ctx, true, 100));
rtc->drawTexture(GrNoClip(), sk_ref_sp(topLeftRTC->asTextureProxy()),
GrSamplerState::Filter::kNearest, 0xffffffff, {0, 0, 100, 200},
{100, 0, 200, 200}, GrQuadAAFlags::kNone,
SkCanvas::SrcRectConstraint::kStrict_SrcRectConstraint, SkMatrix::I(),
nullptr, nullptr);
}
// Draw the test to an off-screen, bottom-up render target.
if (auto topLeftRTC = ctx->contextPriv().makeDeferredRenderTargetContext(
SkBackingFit::kExact, 100, 200, rtc->asSurfaceProxy()->config(),
nullptr, 1, GrMipMapped::kNo, kBottomLeft_GrSurfaceOrigin, nullptr,
SkBudgeted::kYes)) {
topLeftRTC->clear(nullptr, 0, GrRenderTargetContext::CanClearFullscreen::kYes);
topLeftRTC->priv().testingOnly_addDrawOp(ClockwiseTestOp::Make(ctx, false, 0));
topLeftRTC->priv().testingOnly_addDrawOp(ClockwiseTestOp::Make(ctx, true, 100));
rtc->drawTexture(GrNoClip(), sk_ref_sp(topLeftRTC->asTextureProxy()),
GrSamplerState::Filter::kNearest, 0xffffffff, {0, 0, 100, 200},
{200, 0, 300, 200}, GrQuadAAFlags::kNone,
SkCanvas::SrcRectConstraint::kStrict_SrcRectConstraint, SkMatrix::I(),
nullptr, nullptr);
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////
DEF_GM( return new ClockwiseGM(); )
}