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#include "SampleCode.h"
#include "SkCanvas.h"
#include "SkPaint.h"
#include "SkView.h"
///////////////////////////////////////////////////////////////////////////////
class LayerMaskView : public SkView {
public:
LayerMaskView() {}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "LayerMask");
return true;
}
return this->INHERITED::onQuery(evt);
}
void drawMask(SkCanvas* canvas, const SkRect& r) {
SkPaint paint;
paint.setAntiAlias(true);
if (true) {
SkBitmap mask;
int w = SkScalarRound(r.width());
int h = SkScalarRound(r.height());
mask.setConfig(SkBitmap::kARGB_8888_Config, w, h);
mask.allocPixels();
mask.eraseColor(0);
SkCanvas c(mask);
SkRect bounds = r;
bounds.offset(-bounds.fLeft, -bounds.fTop);
c.drawOval(bounds, paint);
paint.setXfermodeMode(SkXfermode::kDstIn_Mode);
canvas->drawBitmap(mask, r.fLeft, r.fTop, &paint);
} else {
SkPath p;
p.addOval(r);
p.setFillType(SkPath::kInverseWinding_FillType);
paint.setXfermodeMode(SkXfermode::kDstOut_Mode);
canvas->drawPath(p, paint);
}
}
void drawBG(SkCanvas* canvas) {
canvas->drawColor(0xFFDDDDDD);
}
virtual void onDraw(SkCanvas* canvas) {
this->drawBG(canvas);
SkRect r;
r.set(SkIntToScalar(20), SkIntToScalar(20), SkIntToScalar(120), SkIntToScalar(120));
canvas->saveLayer(&r, NULL, SkCanvas::kARGB_ClipLayer_SaveFlag);
canvas->drawColor(SK_ColorRED);
drawMask(canvas, r);
canvas->restore();
}
private:
typedef SkView INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new LayerMaskView; }
static SkViewRegister reg(MyFactory);
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