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/*
* 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 "SkAnimTimer.h"
#include "SkPath.h"
#include "SkDashPathEffect.h"
int dash1[] = { 1, 1 };
int dash2[] = { 1, 3 };
int dash3[] = { 1, 1, 3, 3 };
int dash4[] = { 1, 3, 2, 4 };
struct DashExample {
int* pattern;
int length;
} dashExamples[] = {
{ dash1, SK_ARRAY_COUNT(dash1) },
{ dash2, SK_ARRAY_COUNT(dash2) },
{ dash3, SK_ARRAY_COUNT(dash3) },
{ dash4, SK_ARRAY_COUNT(dash4) }
};
class DashCircleGM : public skiagm::GM {
public:
DashCircleGM() : fRotation(0) { }
protected:
SkString onShortName() override { return SkString("dashcircle"); }
SkISize onISize() override { return SkISize::Make(900, 1200); }
void onDraw(SkCanvas* canvas) override {
SkPaint refPaint;
refPaint.setAntiAlias(true);
refPaint.setColor(0xFFbf3f7f);
refPaint.setStyle(SkPaint::kStroke_Style);
refPaint.setStrokeWidth(1);
const SkScalar radius = 125;
SkRect oval = SkRect::MakeLTRB(-radius - 20, -radius - 20, radius + 20, radius + 20);
SkPath circle;
circle.addCircle(0, 0, radius);
SkScalar circumference = radius * SK_ScalarPI * 2;
int wedges[] = { 6, 12, 36 };
canvas->translate(radius+20, radius+20);
for (int wedge : wedges) {
SkScalar arcLength = 360.f / wedge;
canvas->save();
for (const DashExample& dashExample : dashExamples) {
SkPath refPath;
int dashUnits = 0;
for (int index = 0; index < dashExample.length; ++index) {
dashUnits += dashExample.pattern[index];
}
SkScalar unitLength = arcLength / dashUnits;
SkScalar angle = 0;
for (int index = 0; index < wedge; ++index) {
for (int i2 = 0; i2 < dashExample.length; i2 += 2) {
SkScalar span = dashExample.pattern[i2] * unitLength;
refPath.moveTo(0, 0);
refPath.arcTo(oval, angle, span, false);
refPath.close();
angle += span + (dashExample.pattern[i2 + 1]) * unitLength;
}
}
canvas->save();
canvas->rotate(fRotation);
canvas->drawPath(refPath, refPaint);
canvas->restore();
SkPaint p;
p.setAntiAlias(true);
p.setStyle(SkPaint::kStroke_Style);
p.setStrokeWidth(10);
SkScalar intervals[4];
int intervalCount = dashExample.length;
SkScalar dashLength = circumference / wedge / dashUnits;
for (int index = 0; index < dashExample.length; ++index) {
intervals[index] = dashExample.pattern[index] * dashLength;
}
p.setPathEffect(SkDashPathEffect::Make(intervals, intervalCount, 0));
canvas->save();
canvas->rotate(fRotation);
canvas->drawPath(circle, p);
canvas->restore();
canvas->translate(0, radius * 2 + 50);
}
canvas->restore();
canvas->translate(radius * 2 + 50, 0);
}
}
bool onAnimate(const SkAnimTimer& timer) override {
constexpr SkScalar kDesiredDurationSecs = 100.0f;
fRotation = timer.scaled(360.0f/kDesiredDurationSecs, 360.0f);
return true;
}
private:
SkScalar fRotation;
typedef GM INHERITED;
};
DEF_GM(return new DashCircleGM; )
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