skia2/gm/discard.cpp
Brian Salomon eebe735dea GrRenderTargetContext->GrSurfaceDrawContext
Just the class/files. variable names and additional comments to follow.

Change-Id: Ic03d07fd5009eaf3d706c2536486a117328963fc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/342617
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
2020-12-10 18:51:19 +00:00

102 lines
3.0 KiB
C++

/*
* Copyright 2014 Google Inc.
*
* 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/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkPaint.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkShader.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkSurface.h"
#include "include/core/SkTypes.h"
#include "include/gpu/GrDirectContext.h"
#include "include/gpu/GrRecordingContext.h"
#include "include/utils/SkRandom.h"
#include "tools/ToolUtils.h"
class GrSurfaceDrawContext;
namespace skiagm {
/*
* This GM exercises SkCanvas::discard() by creating an offscreen SkSurface and repeatedly
* discarding it, drawing to it, and then drawing it to the main canvas.
*/
class DiscardGM : public GpuGM {
public:
DiscardGM() {}
protected:
SkString onShortName() override {
return SkString("discard");
}
SkISize onISize() override {
return SkISize::Make(100, 100);
}
DrawResult onDraw(GrRecordingContext* context, GrSurfaceDrawContext*, SkCanvas* canvas,
SkString* errorMsg) override {
auto direct = context->asDirectContext();
if (!direct) {
*errorMsg = "GM relies on having access to a live direct context.";
return DrawResult::kSkip;
}
SkISize size = this->getISize();
size.fWidth /= 10;
size.fHeight /= 10;
SkImageInfo info = SkImageInfo::MakeN32Premul(size);
sk_sp<SkSurface> surface = SkSurface::MakeRenderTarget(direct, SkBudgeted::kNo, info);
if (nullptr == surface) {
*errorMsg = "Could not create render target.";
return DrawResult::kFail;
}
canvas->clear(SK_ColorBLACK);
SkRandom rand;
for (int x = 0; x < 10; ++x) {
for (int y = 0; y < 10; ++y) {
surface->getCanvas()->discard();
// Make something that isn't too close to the background color, black.
SkColor color = ToolUtils::color_to_565(rand.nextU() | 0xFF404040);
switch (rand.nextULessThan(3)) {
case 0:
surface->getCanvas()->drawColor(color);
break;
case 1:
surface->getCanvas()->clear(color);
break;
case 2:
SkPaint paint;
paint.setShader(SkShaders::Color(color));
surface->getCanvas()->drawPaint(paint);
break;
}
surface->draw(canvas, 10.f*x, 10.f*y, nullptr);
}
}
surface->getCanvas()->discard();
return DrawResult::kOk;
}
private:
using INHERITED = GM;
};
//////////////////////////////////////////////////////////////////////////////
DEF_GM(return new DiscardGM;)
} // namespace skiagm