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/*
* Copyright 2015 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 "SkGradientShader.h"
#include "SkImage.h"
#include "SkPath.h"
#include "SkSurface.h"
static sk_sp<SkImage> make_image(SkCanvas* origCanvas, int w, int h) {
SkImageInfo info = SkImageInfo::MakeN32Premul(w, h);
auto surface(origCanvas->makeSurface(info));
if (nullptr == surface) {
surface = SkSurface::MakeRaster(info);
}
SkCanvas* canvas = surface->getCanvas();
sk_tool_utils::draw_checkerboard(canvas, SK_ColorRED, SK_ColorGREEN, w/10);
return surface->makeImageSnapshot();
}
namespace skiagm {
class PerspShadersGM : public GM {
public:
PerspShadersGM(bool doAA) : fDoAA(doAA) { }
protected:
SkString onShortName() override {
SkString name;
name.printf("persp_shaders_%s",
fDoAA ? "aa" : "bw");
return name;
}
SkISize onISize() override {
return SkISize::Make(kCellSize*kNumCols, kCellSize*kNumRows);
}
void onOnceBeforeDraw() override {
fBitmap = sk_tool_utils::create_checkerboard_bitmap(kCellSize, kCellSize,
SK_ColorBLUE, SK_ColorYELLOW,
kCellSize/10);
fBitmapShader = SkShader::MakeBitmapShader(fBitmap, SkShader::kClamp_TileMode,
SkShader::kClamp_TileMode);
SkPoint pts1[] = {
{ 0, 0 },
{ SkIntToScalar(kCellSize), SkIntToScalar(kCellSize) }
};
SkPoint pts2[] = {
{ 0, 0 },
{ 0, SkIntToScalar(kCellSize) }
};
static const SkColor colors[] = {
SK_ColorRED, SK_ColorGREEN, SK_ColorRED, SK_ColorGREEN, SK_ColorRED
};
static const SkScalar pos[] = { 0, 0.25f, 0.5f, 0.75f, SK_Scalar1 };
fLinearGrad1 = SkGradientShader::MakeLinear(pts1, colors, pos, SK_ARRAY_COUNT(colors),
SkShader::kClamp_TileMode);
fLinearGrad2 = SkGradientShader::MakeLinear(pts2, colors, pos, SK_ARRAY_COUNT(colors),
SkShader::kClamp_TileMode);
fPerspMatrix.reset();
fPerspMatrix.setPerspY(SK_Scalar1 / 50);
fPath.moveTo(0, 0);
fPath.lineTo(0, SkIntToScalar(kCellSize));
fPath.lineTo(kCellSize/2.0f, kCellSize/2.0f);
fPath.lineTo(SkIntToScalar(kCellSize), SkIntToScalar(kCellSize));
fPath.lineTo(SkIntToScalar(kCellSize), 0);
fPath.close();
}
void drawRow(SkCanvas* canvas, SkFilterQuality filterQ) {
SkPaint filterPaint;
filterPaint.setFilterQuality(filterQ);
filterPaint.setAntiAlias(fDoAA);
SkPaint pathPaint;
pathPaint.setShader(fBitmapShader);
pathPaint.setFilterQuality(filterQ);
pathPaint.setAntiAlias(fDoAA);
SkPaint gradPaint1;
gradPaint1.setShader(fLinearGrad1);
gradPaint1.setAntiAlias(fDoAA);
SkPaint gradPaint2;
gradPaint2.setShader(fLinearGrad2);
gradPaint2.setAntiAlias(fDoAA);
SkRect r = SkRect::MakeWH(SkIntToScalar(kCellSize), SkIntToScalar(kCellSize));
canvas->save();
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawBitmapRect(fBitmap, r, &filterPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawImage(fImage.get(), 0, 0, &filterPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawRect(r, pathPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawPath(fPath, pathPaint);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawRect(r, gradPaint1);
canvas->restore();
canvas->translate(SkIntToScalar(kCellSize), 0);
canvas->save();
canvas->concat(fPerspMatrix);
canvas->drawPath(fPath, gradPaint2);
canvas->restore();
canvas->restore();
}
void onDraw(SkCanvas* canvas) override {
if (!fImage) {
fImage = make_image(canvas, kCellSize, kCellSize);
}
this->drawRow(canvas, kNone_SkFilterQuality);
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, kLow_SkFilterQuality);
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, kMedium_SkFilterQuality);
canvas->translate(0, SkIntToScalar(kCellSize));
this->drawRow(canvas, kHigh_SkFilterQuality);
canvas->translate(0, SkIntToScalar(kCellSize));
}
private:
static const int kCellSize = 50;
static const int kNumRows = 4;
static const int kNumCols = 6;
bool fDoAA;
SkPath fPath;
sk_sp<SkShader> fBitmapShader;
sk_sp<SkShader> fLinearGrad1;
sk_sp<SkShader> fLinearGrad2;
SkMatrix fPerspMatrix;
sk_sp<SkImage> fImage;
SkBitmap fBitmap;
typedef GM INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
DEF_GM(return new PerspShadersGM(true);)
DEF_GM(return new PerspShadersGM(false);)
}
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