skia2/gm/shapes.cpp

165 lines
5.5 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.h"
#include "SkRandom.h"
#include "SkRRect.h"
namespace skiagm {
/*
* This is the base class for two GMs that cover various corner cases with primitive Skia shapes
* (zero radius, near-zero radius, inner shape overlap, etc.) It uses an xfermode of darken to help
* double-blended and/or dropped pixels stand out.
*/
class ShapesGM : public GM {
protected:
ShapesGM(const char* name, bool antialias) : fName(name), fAntialias(antialias) {
fShapes.push_back().setOval(SkRect::MakeXYWH(-5, 25, 200, 100));
fRotations.push_back(21);
fShapes.push_back().setRect(SkRect::MakeXYWH(95, 75, 125, 100));
fRotations.push_back(94);
fShapes.push_back().setRectXY(SkRect::MakeXYWH(0, 75, 150, 100), 1e-5f, 1e-5f);
fRotations.push_back(132);
fShapes.push_back().setRectXY(SkRect::MakeXYWH(15, -20, 100, 100), 20, 15);
fRotations.push_back(282);
fSimpleShapeCount = fShapes.count();
fShapes.push_back().setNinePatch(SkRect::MakeXYWH(140, -50, 90, 110), 10, 5, 25, 35);
fRotations.push_back(0);
fShapes.push_back().setNinePatch(SkRect::MakeXYWH(160, -60, 60, 90), 10, 60, 50, 30);
fRotations.push_back(-35);
fShapes.push_back().setNinePatch(SkRect::MakeXYWH(220, -120, 60, 90), 1, 89, 59, 1);
fRotations.push_back(65);
SkVector radii[4] = {{4, 6}, {12, 8}, {24, 16}, {32, 48}};
fShapes.push_back().setRectRadii(SkRect::MakeXYWH(150, -129, 80, 160), radii);
fRotations.push_back(265);
SkVector radii2[4] = {{0, 0}, {80, 60}, {0, 0}, {80, 60}};
fShapes.push_back().setRectRadii(SkRect::MakeXYWH(180, -30, 80, 60), radii2);
fRotations.push_back(295);
if (!antialias) {
fName.append("_bw");
}
}
SkString onShortName() override final { return fName; }
SkISize onISize() override { return SkISize::Make(500, 500); }
void onOnceBeforeDraw() override {
fPaint.setXfermodeMode(SkXfermode::kDarken_Mode);
fPaint.setAntiAlias(fAntialias);
}
void onDraw(SkCanvas* canvas) override {
canvas->clear(SK_ColorWHITE);
canvas->save();
canvas->translate(canvas->imageInfo().width() / 2.f, canvas->imageInfo().height() / 2.f);
this->drawShapes(canvas);
canvas->restore();
}
virtual void drawShapes(SkCanvas* canvas) const = 0;
protected:
SkString fName;
bool fAntialias;
SkPaint fPaint;
SkTArray<SkRRect> fShapes;
SkTArray<SkScalar> fRotations;
int fSimpleShapeCount;
private:
typedef GM INHERITED;
};
class SimpleShapesGM : public ShapesGM {
public:
SimpleShapesGM(bool antialias) : INHERITED("simpleshapes", antialias) {}
private:
void drawShapes(SkCanvas* canvas) const override {
SkRandom rand(2);
for (int i = 0; i < fShapes.count(); i++) {
SkPaint paint(fPaint);
paint.setColor(rand.nextU() & ~0x808080);
paint.setAlpha(128); // Use alpha to detect double blends.
const SkRRect& shape = fShapes[i];
canvas->save();
canvas->rotate(fRotations[i]);
switch (shape.getType()) {
case SkRRect::kRect_Type:
canvas->drawRect(shape.rect(), paint);
break;
case SkRRect::kOval_Type:
canvas->drawOval(shape.rect(), paint);
break;
default:
canvas->drawRRect(shape, paint);
break;
}
canvas->restore();
}
}
typedef ShapesGM INHERITED;
};
class InnerShapesGM : public ShapesGM {
public:
InnerShapesGM(bool antialias) : INHERITED("innershapes", antialias) {}
private:
void drawShapes(SkCanvas* canvas) const override {
SkRandom rand;
for (int i = 0; i < fShapes.count(); i++) {
const SkRRect& outer = fShapes[i];
const SkRRect& inner = fShapes[(i * 7 + 11) % fSimpleShapeCount];
float s = 0.95f * SkTMin(outer.rect().width() / inner.rect().width(),
outer.rect().height() / inner.rect().height());
SkMatrix innerXform;
float dx = (rand.nextF() - 0.5f) * (outer.rect().width() - s * inner.rect().width());
float dy = (rand.nextF() - 0.5f) * (outer.rect().height() - s * inner.rect().height());
innerXform.setTranslate(outer.rect().centerX() + dx, outer.rect().centerY() + dy);
if (s < 1) {
innerXform.preScale(s, s);
}
innerXform.preTranslate(-inner.rect().centerX(), -inner.rect().centerY());
SkRRect xformedInner;
inner.transform(innerXform, &xformedInner);
SkPaint paint(fPaint);
paint.setColor(rand.nextU() & ~0x808080);
paint.setAlpha(128); // Use alpha to detect double blends.
canvas->save();
canvas->rotate(fRotations[i]);
canvas->drawDRRect(outer, xformedInner, paint);
canvas->restore();
}
}
typedef ShapesGM INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
DEF_GM( return new SimpleShapesGM(true); )
DEF_GM( return new SimpleShapesGM(false); )
DEF_GM( return new InnerShapesGM(true); )
DEF_GM( return new InnerShapesGM(false); )
}