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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 "SkView.h"
#include "SkCanvas.h"
#include "SkCornerPathEffect.h"
#include "SkCullPoints.h"
#include "SkGradientShader.h"
#include "SkPath.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkUtils.h"
#include "SkRandom.h"
static void addbump(SkPath* path, const SkPoint pts[2], SkScalar bump) {
SkVector tang;
tang.setLength(pts[1].fX - pts[0].fX, pts[1].fY - pts[0].fY, bump);
path->lineTo(SkScalarHalf(pts[0].fX + pts[1].fX) - tang.fY,
SkScalarHalf(pts[0].fY + pts[1].fY) + tang.fX);
path->lineTo(pts[1]);
}
static void subdivide(SkPath* path, SkScalar bump) {
SkPath::Iter iter(*path, false);
SkPoint pts[4];
SkPath tmp;
for (;;)
switch (iter.next(pts)) {
case SkPath::kMove_Verb:
tmp.moveTo(pts[0]);
break;
case SkPath::kLine_Verb:
addbump(&tmp, pts, bump);
bump = -bump;
break;
case SkPath::kDone_Verb:
goto FINISH;
default:
break;
}
FINISH:
path->swap(tmp);
}
static SkIPoint* getpts(const SkPath& path, int* count) {
SkPoint pts[4];
int n = 1;
SkIPoint* array;
{
SkPath::Iter iter(path, false);
for (;;)
switch (iter.next(pts)) {
case SkPath::kLine_Verb:
n += 1;
break;
case SkPath::kDone_Verb:
goto FINISHED;
default:
break;
}
}
FINISHED:
array = new SkIPoint[n];
n = 0;
{
SkPath::Iter iter(path, false);
for (;;)
switch (iter.next(pts)) {
case SkPath::kMove_Verb:
array[n++].set(SkScalarRoundToInt(pts[0].fX),
SkScalarRoundToInt(pts[0].fY));
break;
case SkPath::kLine_Verb:
array[n++].set(SkScalarRoundToInt(pts[1].fX),
SkScalarRoundToInt(pts[1].fY));
break;
case SkPath::kDone_Verb:
goto FINISHED2;
default:
break;
}
}
FINISHED2:
*count = n;
return array;
}
static SkScalar nextScalarRange(SkRandom& rand, SkScalar min, SkScalar max) {
return min + SkScalarMul(rand.nextUScalar1(), max - min);
}
class CullView : public SampleView {
public:
CullView() {
fClip.set(0, 0, SkIntToScalar(160), SkIntToScalar(160));
SkRandom rand;
for (int i = 0; i < 50; i++) {
SkScalar x = nextScalarRange(rand, -fClip.width()*1, fClip.width()*2);
SkScalar y = nextScalarRange(rand, -fClip.height()*1, fClip.height()*2);
if (i == 0)
fPath.moveTo(x, y);
else
fPath.lineTo(x, y);
}
SkScalar bump = fClip.width()/8;
subdivide(&fPath, bump);
subdivide(&fPath, bump);
subdivide(&fPath, bump);
fPoints = getpts(fPath, &fPtCount);
this->setBGColor(0xFFDDDDDD);
}
virtual ~CullView() {
delete[] fPoints;
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Culling");
return true;
}
return this->INHERITED::onQuery(evt);
}
virtual void onDrawContent(SkCanvas* canvas) {
SkAutoCanvasRestore ar(canvas, true);
canvas->translate( SkScalarHalf(this->width() - fClip.width()),
SkScalarHalf(this->height() - fClip.height()));
// canvas->scale(SK_Scalar1*3, SK_Scalar1*3, 0, 0);
SkPaint paint;
// paint.setAntiAliasOn(true);
paint.setStyle(SkPaint::kStroke_Style);
canvas->drawRect(fClip, paint);
#if 1
paint.setColor(0xFF555555);
paint.setStrokeWidth(SkIntToScalar(2));
// paint.setPathEffect(new SkCornerPathEffect(SkIntToScalar(30)))->unref();
canvas->drawPath(fPath, paint);
// paint.setPathEffect(NULL);
#endif
SkPath tmp;
SkIRect iclip;
fClip.round(&iclip);
SkCullPointsPath cpp(iclip, &tmp);
cpp.moveTo(fPoints[0].fX, fPoints[0].fY);
for (int i = 0; i < fPtCount; i++)
cpp.lineTo(fPoints[i].fX, fPoints[i].fY);
paint.setColor(SK_ColorRED);
paint.setStrokeWidth(SkIntToScalar(3));
paint.setStrokeJoin(SkPaint::kRound_Join);
canvas->drawPath(tmp, paint);
this->inval(NULL);
}
private:
SkRect fClip;
SkIPoint* fPoints;
SkPath fPath;
int fPtCount;
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new CullView; }
static SkViewRegister reg(MyFactory);
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