arcofzorro.cpp

Go to the documentation of this file.

/*
 * Copyright 2013 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/SkPaint.h"
#include "include/core/SkRect.h"
#include "include/core/SkScalar.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "src/base/SkRandom.h"
 
namespace skiagm {
 
// This GM draws a lot of arcs in a 'Z' shape. It particularly exercises
// the 'drawArc' code near a singularly of its processing (i.e., near the
// edge of one of its underlying quads).
class ArcOfZorroGM : public GM {
public:
    ArcOfZorroGM() {
        this->setBGColor(0xFFCCCCCC);
    }
 
protected:
    SkString getName() const override { return SkString("arcofzorro"); }
 
    SkISize getISize() override { return SkISize::Make(1000, 1000); }
 
    void onDraw(SkCanvas* canvas) override {
        SkRandom rand;
 
        SkRect rect = SkRect::MakeXYWH(10, 10, 200, 200);
 
        SkPaint p;
 
        p.setStyle(SkPaint::kStroke_Style);
        p.setStrokeWidth(35);
        int xOffset = 0, yOffset = 0;
        int direction = 0;
 
        for (float arc = 134.0f; arc < 136.0f; arc += 0.01f) {
            SkColor color = rand.nextU();
            color |= 0xff000000;
            p.setColor(color);
 
            canvas->save();
            canvas->translate(SkIntToScalar(xOffset), SkIntToScalar(yOffset));
            canvas->drawArc(rect, 0, arc, false, p);
            canvas->restore();
 
            switch (direction) {
            case 0:
                xOffset += 10;
                if (xOffset >= 700) {
                    direction = 1;
                }
                break;
            case 1:
                xOffset -= 10;
                yOffset += 10;
                if (xOffset < 50) {
                    direction = 2;
                }
                break;
            case 2:
                xOffset += 10;
                break;
            }
        }
 
    }
 
private:
    using INHERITED = GM;
};
 
//////////////////////////////////////////////////////////////////////////////
 
DEF_GM(return new ArcOfZorroGM;)
}  // namespace skiagm