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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 "Sk64.h"
#include "SkGradientShader.h"
static void draw_gradient2(SkCanvas* canvas, const SkRect& rect, SkScalar delta) {
SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorMAGENTA };
SkScalar pos[] = { 0, SkFloatToScalar(0.25f), SkFloatToScalar(0.75f), SK_Scalar1 };
SkScalar l = rect.fLeft;
SkScalar t = rect.fTop;
SkScalar w = rect.width();
SkScalar h = rect.height();
SkASSERT(0 == SkScalarMod(w, SK_Scalar1 * 5));
SkPoint c0 = { l + 2 * w / 5 + delta, t + h / 2 };
SkPoint c1 = { l + 3 * w / 5, t + h / 2 };
SkScalar r0 = w / 5;
SkScalar r1 = 2 * w / 5;
SkShader* s = SkGradientShader::CreateTwoPointRadial(c0, r0, c1, r1, colors,
pos, SK_ARRAY_COUNT(pos),
SkShader::kClamp_TileMode);
SkPaint paint;
paint.setShader(s)->unref();
canvas->drawRect(rect, paint);
}
class DegenerateTwoPtRadialsView : public SampleView {
public:
DegenerateTwoPtRadialsView() {
fTime = 0;
this->setBGColor(0xFFDDDDDD);
}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "DegenerateTwoPtRadials");
return true;
}
return this->INHERITED::onQuery(evt);
}
virtual void onDrawContent(SkCanvas* canvas) {
fTime += SampleCode::GetAnimSecondsDelta();
SkScalar delta = fTime / 15.f;
int intPart = SkScalarFloor(delta);
delta = delta - SK_Scalar1 * intPart;
if (intPart % 2) {
delta = SK_Scalar1 - delta;
}
delta -= SK_ScalarHalf;
static const int DELTA_SCALE = 500;
delta /= DELTA_SCALE;
SkRect rect;
SkScalar w = SK_Scalar1 * 500;
SkScalar h = SK_Scalar1 * 500;
SkScalar l = SK_Scalar1 * 100;
SkScalar t = SK_Scalar1 * 100;
draw_gradient2(canvas, SkRect::MakeXYWH(l, t, w, h), delta);
char txt[512];
sprintf(txt, "gap at \"tangent\" pt = %f", SkScalarToFloat(delta));
SkPaint paint;
paint.setAntiAlias(true);
paint.setColor(SK_ColorBLACK);
canvas->drawText(txt, strlen(txt), l + w/2 + w*DELTA_SCALE*delta, t + h + SK_Scalar1 * 10, paint);
this->inval(NULL);
}
private:
SkScalar fTime;
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new DegenerateTwoPtRadialsView; }
static SkViewRegister reg(MyFactory);
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