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#include "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkGradientShader.h"
#include "SkGraphics.h"
#include "SkImageDecoder.h"
#include "SkPath.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkUtils.h"
#include "SkXfermode.h"
#include "SkColorPriv.h"
#include "SkColorFilter.h"
#include "SkTime.h"
#include "SkRandom.h"
#include "SkLineClipper.h"
#include "SkEdgeClipper.h"
#define AUTO_ANIMATE true
static int test0(SkPoint pts[], SkRect* clip) {
pts[0].set(200000, 140);
pts[1].set(-740000, 483);
pts[2].set(1.00000102e-06f, 9.10000017e-05f);
clip->set(0, 0, 640, 480);
return 2;
}
///////////////////////////////////////////////////////////////////////////////
static void drawQuad(SkCanvas* canvas, const SkPoint pts[3], const SkPaint& p) {
SkPath path;
path.moveTo(pts[0]);
path.quadTo(pts[1], pts[2]);
canvas->drawPath(path, p);
}
static void drawCubic(SkCanvas* canvas, const SkPoint pts[4], const SkPaint& p) {
SkPath path;
path.moveTo(pts[0]);
path.cubicTo(pts[1], pts[2], pts[3]);
canvas->drawPath(path, p);
}
typedef void (*clipper_proc)(const SkPoint src[], const SkRect& clip,
SkCanvas*, const SkPaint&, const SkPaint&);
static void check_clipper(int count, const SkPoint pts[], const SkRect& clip) {
for (int i = 0; i < count; i++) {
SkASSERT(pts[i].fX >= clip.fLeft);
SkASSERT(pts[i].fX <= clip.fRight);
SkASSERT(pts[i].fY >= clip.fTop);
SkASSERT(pts[i].fY <= clip.fBottom);
}
if (count > 1) {
sk_assert_monotonic_y(pts, count);
}
}
static void line_intersector(const SkPoint src[], const SkRect& clip,
SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
canvas->drawPoints(SkCanvas::kLines_PointMode, 2, src, p1);
SkPoint dst[2];
if (SkLineClipper::IntersectLine(src, clip, dst)) {
check_clipper(2, dst, clip);
canvas->drawPoints(SkCanvas::kLines_PointMode, 2, dst, p0);
}
}
static void line_clipper(const SkPoint src[], const SkRect& clip,
SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
canvas->drawPoints(SkCanvas::kLines_PointMode, 2, src, p1);
SkPoint dst[SkLineClipper::kMaxPoints];
int count = SkLineClipper::ClipLine(src, clip, dst);
for (int i = 0; i < count; i++) {
check_clipper(2, &dst[i], clip);
canvas->drawPoints(SkCanvas::kLines_PointMode, 2, &dst[i], p0);
}
}
static void quad_clipper(const SkPoint src[], const SkRect& clip,
SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
drawQuad(canvas, src, p1);
SkEdgeClipper clipper;
if (clipper.clipQuad(src, clip)) {
SkPoint pts[3];
SkPath::Verb verb;
while ((verb = clipper.next(pts)) != SkPath::kDone_Verb) {
switch (verb) {
case SkPath::kLine_Verb:
check_clipper(2, pts, clip);
canvas->drawPoints(SkCanvas::kLines_PointMode, 2, pts, p0);
break;
case SkPath::kQuad_Verb:
check_clipper(3, pts, clip);
drawQuad(canvas, pts, p0);
break;
default:
SkASSERT(!"unexpected verb");
}
}
}
}
static void cubic_clipper(const SkPoint src[], const SkRect& clip,
SkCanvas* canvas, const SkPaint& p0, const SkPaint& p1) {
drawCubic(canvas, src, p1);
SkEdgeClipper clipper;
if (clipper.clipCubic(src, clip)) {
SkPoint pts[4];
SkPath::Verb verb;
while ((verb = clipper.next(pts)) != SkPath::kDone_Verb) {
switch (verb) {
case SkPath::kLine_Verb:
check_clipper(2, pts, clip);
canvas->drawPoints(SkCanvas::kLines_PointMode, 2, pts, p0);
break;
case SkPath::kCubic_Verb:
// check_clipper(4, pts, clip);
drawCubic(canvas, pts, p0);
break;
default:
SkASSERT(!"unexpected verb");
}
}
}
}
static const clipper_proc gProcs[] = {
line_intersector,
line_clipper,
quad_clipper,
cubic_clipper
};
///////////////////////////////////////////////////////////////////////////////
enum {
W = 640/3,
H = 480/3
};
class LineClipperView : public SkView {
SkMSec fNow;
int fCounter;
int fProcIndex;
SkRect fClip;
SkRandom fRand;
SkPoint fPts[4];
void randPts() {
for (int i = 0; i < SK_ARRAY_COUNT(fPts); i++) {
fPts[i].set(fRand.nextUScalar1() * 640,
fRand.nextUScalar1() * 480);
}
fCounter += 1;
}
public:
LineClipperView() {
fProcIndex = 0;
fCounter = 0;
int x = (640 - W)/2;
int y = (480 - H)/2;
fClip.set(x, y, x + W, y + H);
this->randPts();
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "LineClipper");
return true;
}
return this->INHERITED::onQuery(evt);
}
void drawBG(SkCanvas* canvas) {
canvas->drawColor(SK_ColorWHITE);
}
static void drawVLine(SkCanvas* canvas, SkScalar x, const SkPaint& paint) {
canvas->drawLine(x, -999, x, 999, paint);
}
static void drawHLine(SkCanvas* canvas, SkScalar y, const SkPaint& paint) {
canvas->drawLine(-999, y, 999, y, paint);
}
virtual void onDraw(SkCanvas* canvas) {
this->drawBG(canvas);
SkMSec now = SampleCode::GetAnimTime();
if (fNow != now) {
fNow = now;
this->randPts();
this->inval(NULL);
}
// fProcIndex = test0(fPts, &fClip);
SkPaint paint, paint1;
drawVLine(canvas, fClip.fLeft + SK_ScalarHalf, paint);
drawVLine(canvas, fClip.fRight - SK_ScalarHalf, paint);
drawHLine(canvas, fClip.fTop + SK_ScalarHalf, paint);
drawHLine(canvas, fClip.fBottom - SK_ScalarHalf, paint);
paint.setColor(SK_ColorLTGRAY);
canvas->drawRect(fClip, paint);
paint.setAntiAlias(true);
paint.setColor(SK_ColorBLUE);
paint.setStyle(SkPaint::kStroke_Style);
// paint.setStrokeWidth(SkIntToScalar(3));
paint.setStrokeCap(SkPaint::kRound_Cap);
paint1.setAntiAlias(true);
paint1.setColor(SK_ColorRED);
paint1.setStyle(SkPaint::kStroke_Style);
gProcs[fProcIndex](fPts, fClip, canvas, paint, paint1);
}
virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y) {
// fProcIndex = (fProcIndex + 1) % SK_ARRAY_COUNT(gProcs);
if (x < 50 && y < 50) {
this->randPts();
}
this->inval(NULL);
return NULL;
}
virtual bool onClick(Click* click) {
return false;
}
private:
typedef SkView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new LineClipperView; }
static SkViewRegister reg(MyFactory);
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