skia2/gm/filterbug.cpp
John Stiles ec9b4aab87 Enable ClangTidy check readability-const-return-type.
https://clang.llvm.org/extra/clang-tidy/checks/readability-const-return-type.html

`const` on a non-pointer/reference return type typically doesn't add
value and can have negative side effects. (i.e., returning a
`const std::string` isn't meaningfully different from returning a
`std::string`, but can sometimes inhibit move-related optimizations.)

In Skia's case, the priv() functions are a notable exception where const
return types are intentional and valuable. These calls have been marked
with NOLINT to exclude them from the check.

This check does not affect pointer and reference returns, where
constness is important.

Change-Id: I86cab92332f164e5ab710b4127182eec99831d7d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/308564
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
2020-08-07 17:42:38 +00:00

112 lines
3.3 KiB
C++

/*
* Copyright 2016 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/SkBitmap.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkColorPriv.h"
#include "include/core/SkFilterQuality.h"
#include "include/core/SkImage.h"
#include "include/core/SkImageInfo.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkRect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkShader.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkTileMode.h"
static sk_sp<SkImage> make_image(int firstBlackRow, int lastBlackRow) {
static const int kWidth = 25;
static const int kHeight = 27;
SkBitmap bm;
bm.allocN32Pixels(kWidth, kHeight);
bm.eraseColor(SK_ColorWHITE);
for (int y = firstBlackRow; y < lastBlackRow; ++y) {
for (int x = 0; x < kWidth; ++x) {
*bm.getAddr32(x, y) = SkPackARGB32(0xFF, 0x0, 0x0, 0x0);
}
}
bm.setAlphaType(SkAlphaType::kOpaque_SkAlphaType);
bm.setImmutable();
return SkImage::MakeFromBitmap(bm);
}
// GM to reproduce crbug.com/673261.
class FilterBugGM : public skiagm::GM {
public:
FilterBugGM() { this->setBGColor(SK_ColorRED); }
protected:
SkString onShortName() override { return SkString("filterbug"); }
SkISize onISize() override { return SkISize::Make(150, 150); }
void onOnceBeforeDraw() override {
// The top texture has 5 black rows on top and then 22 white rows on the bottom
fTop = make_image(0, 5);
// The bottom texture has 5 black rows on the bottom and then 22 white rows on the top
fBot = make_image(22, 27);
}
void onDraw(SkCanvas* canvas) override {
static const SkFilterQuality kFilterQuality = SkFilterQuality::kHigh_SkFilterQuality;
static const bool kDoAA = true;
{
SkRect r1 = SkRect::MakeXYWH(50.0f, 0.0f, 50.0f, 50.0f);
SkPaint p1;
p1.setAntiAlias(kDoAA);
p1.setFilterQuality(kFilterQuality);
SkMatrix localMat;
localMat.setScaleTranslate(2.0f, 2.0f, 50.0f, 0.0f);
p1.setShader(fTop->makeShader(SkTileMode::kRepeat, SkTileMode::kRepeat, &localMat));
canvas->drawRect(r1, p1);
}
{
SkRect r2 = SkRect::MakeXYWH(50.0f, 50.0f, 50.0f, 36.0f);
SkPaint p2;
p2.setColor(SK_ColorWHITE);
p2.setAntiAlias(kDoAA);
p2.setFilterQuality(kFilterQuality);
canvas->drawRect(r2, p2);
}
{
SkRect r3 = SkRect::MakeXYWH(50.0f, 86.0f, 50.0f, 50.0f);
SkPaint p3;
p3.setAntiAlias(kDoAA);
p3.setFilterQuality(kFilterQuality);
SkMatrix localMat;
localMat.setScaleTranslate(2.0f, 2.0f, 50.0f, 86.0f);
p3.setShader(fBot->makeShader(SkTileMode::kRepeat, SkTileMode::kRepeat, &localMat));
canvas->drawRect(r3, p3);
}
}
private:
sk_sp<SkImage> fTop;
sk_sp<SkImage> fBot;
typedef skiagm::GM INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
DEF_GM(return new FilterBugGM;)