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#include "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkGradientShader.h"
struct GradData {
int fCount;
const SkColor* fColors;
const SkScalar* fPos;
};
static const SkColor gColors[] = {
SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorWHITE, SK_ColorBLACK
};
static const SkScalar gPos0[] = { 0, SK_Scalar1 };
static const SkScalar gPos1[] = { SK_Scalar1/4, SK_Scalar1*3/4 };
static const SkScalar gPos2[] = {
0, SK_Scalar1/8, SK_Scalar1/2, SK_Scalar1*7/8, SK_Scalar1
};
static const GradData gGradData[] = {
{ 2, gColors, NULL },
{ 2, gColors, gPos0 },
{ 2, gColors, gPos1 },
{ 5, gColors, NULL },
{ 5, gColors, gPos2 }
};
static SkShader* MakeLinear(const SkPoint pts[2], const GradData& data,
SkShader::TileMode tm, SkUnitMapper* mapper) {
return SkGradientShader::CreateLinear(pts, data.fColors, data.fPos,
data.fCount, tm, mapper);
}
static SkShader* MakeRadial(const SkPoint pts[2], const GradData& data,
SkShader::TileMode tm, SkUnitMapper* mapper) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::CreateRadial(center, center.fX, data.fColors,
data.fPos, data.fCount, tm, mapper);
}
static SkShader* MakeSweep(const SkPoint pts[2], const GradData& data,
SkShader::TileMode tm, SkUnitMapper* mapper) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::CreateSweep(center.fX, center.fY, data.fColors,
data.fPos, data.fCount, mapper);
}
typedef SkShader* (*GradMaker)(const SkPoint pts[2], const GradData& data,
SkShader::TileMode tm, SkUnitMapper* mapper);
static const GradMaker gGradMakers[] = {
MakeLinear, MakeRadial, MakeSweep
};
///////////////////////////////////////////////////////////////////////////////
class GradientsView : public SkView {
public:
GradientsView() {}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Gradients");
return true;
}
return this->INHERITED::onQuery(evt);
}
void drawBG(SkCanvas* canvas) {
canvas->drawColor(0xFFDDDDDD);
}
virtual void onDraw(SkCanvas* canvas) {
this->drawBG(canvas);
SkPoint pts[2] = {
{ 0, 0 },
{ SkIntToScalar(100), SkIntToScalar(100) }
};
SkShader::TileMode tm = SkShader::kClamp_TileMode;
SkRect r = { 0, 0, SkIntToScalar(100), SkIntToScalar(100) };
SkPaint paint;
paint.setAntiAlias(true);
canvas->translate(SkIntToScalar(20), SkIntToScalar(20));
for (size_t i = 0; i < SK_ARRAY_COUNT(gGradData); i++) {
canvas->save();
for (size_t j = 0; j < SK_ARRAY_COUNT(gGradMakers); j++) {
SkShader* shader = gGradMakers[j](pts, gGradData[i], tm, NULL);
paint.setShader(shader);
canvas->drawRect(r, paint);
shader->unref();
canvas->translate(0, SkIntToScalar(120));
}
canvas->restore();
canvas->translate(SkIntToScalar(120), 0);
}
}
private:
typedef SkView INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new GradientsView; }
static SkViewRegister reg(MyFactory);
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