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/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SampleCode.h"
#include "SkCanvas.h"
#include "SkPaint.h"
#include "SkPath.h"
#include "SkView.h"
// ensure that we don't accidentally screw up the bounds when the oval is
// fractional, and the impl computes the center and radii, and uses them to
// reconstruct the edges of the circle.
// see bug# 1504910
static void test_circlebounds(SkCanvas*) {
SkRect r = { 1.39999998f, 1, 21.3999996f, 21 };
SkPath p;
p.addOval(r);
SkASSERT(r == p.getBounds());
}
class CircleView : public SampleView {
public:
static const SkScalar ANIM_DX;
static const SkScalar ANIM_DY;
static const SkScalar ANIM_RAD;
SkScalar fDX, fDY, fRAD;
CircleView() {
fDX = fDY = fRAD = 0;
fN = 3;
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Circles");
return true;
}
return this->INHERITED::onQuery(evt);
}
void circle(SkCanvas* canvas, int width, bool aa) {
SkPaint paint;
paint.setAntiAlias(aa);
if (width < 0) {
paint.setStyle(SkPaint::kFill_Style);
} else {
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(SkIntToScalar(width));
}
canvas->drawCircle(0, 0, SkIntToScalar(9) + fRAD, paint);
if (false) { // avoid bit rot, suppress warning
test_circlebounds(canvas);
}
}
void drawSix(SkCanvas* canvas, SkScalar dx, SkScalar dy) {
for (int width = -1; width <= 1; width++) {
canvas->save();
circle(canvas, width, false);
canvas->translate(0, dy);
circle(canvas, width, true);
canvas->restore();
canvas->translate(dx, 0);
}
}
static void make_poly(SkPath* path, int n) {
if (n <= 0) {
return;
}
path->incReserve(n + 1);
path->moveTo(SK_Scalar1, 0);
SkScalar step = SK_ScalarPI * 2 / n;
SkScalar angle = 0;
for (int i = 1; i < n; i++) {
angle += step;
SkScalar c, s = SkScalarSinCos(angle, &c);
path->lineTo(c, s);
}
path->close();
}
virtual void onDrawContent(SkCanvas* canvas) {
SkPaint paint;
paint.setAntiAlias(true);
paint.setStyle(SkPaint::kStroke_Style);
SkMatrix matrix;
matrix.setScale(SkIntToScalar(100), SkIntToScalar(100));
matrix.postTranslate(SkIntToScalar(200), SkIntToScalar(200));
canvas->concat(matrix);
for (int n = 3; n < 20; n++) {
SkPath path;
make_poly(&path, n);
SkAutoCanvasRestore acr(canvas, true);
canvas->rotate(SkIntToScalar(10) * (n - 3));
canvas->translate(-SK_Scalar1, 0);
canvas->drawPath(path, paint);
}
}
private:
int fN;
typedef SampleView INHERITED;
};
const SkScalar CircleView::ANIM_DX(SK_Scalar1 / 67);
const SkScalar CircleView::ANIM_DY(SK_Scalar1 / 29);
const SkScalar CircleView::ANIM_RAD(SK_Scalar1 / 19);
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new CircleView; }
static SkViewRegister reg(MyFactory);
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