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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 "SkGradientShader.h"
static sk_sp<SkShader> setgrad(const SkRect& r, SkColor c0, SkColor c1) {
SkColor colors[] = { c0, c1 };
SkPoint pts[] = { { r.fLeft, r.fTop }, { r.fRight, r.fTop } };
return SkGradientShader::MakeLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
}
static void test_alphagradients(SkCanvas* canvas) {
SkRect r;
r.set(SkIntToScalar(10), SkIntToScalar(10),
SkIntToScalar(410), SkIntToScalar(30));
SkPaint p, p2;
p2.setStyle(SkPaint::kStroke_Style);
p.setShader(setgrad(r, 0xFF00FF00, 0x0000FF00));
canvas->drawRect(r, p);
canvas->drawRect(r, p2);
r.offset(0, r.height() + SkIntToScalar(4));
p.setShader(setgrad(r, 0xFF00FF00, 0x00000000));
canvas->drawRect(r, p);
canvas->drawRect(r, p2);
r.offset(0, r.height() + SkIntToScalar(4));
p.setShader(setgrad(r, 0xFF00FF00, 0x00FF0000));
canvas->drawRect(r, p);
canvas->drawRect(r, p2);
}
///////////////////////////////////////////////////////////////////////////////
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, nullptr },
{ 2, gColors, gPos0 },
{ 2, gColors, gPos1 },
{ 5, gColors, nullptr },
{ 5, gColors, gPos2 }
};
static sk_sp<SkShader> MakeLinear(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
return SkGradientShader::MakeLinear(pts, data.fColors, data.fPos, data.fCount, tm);
}
static sk_sp<SkShader> MakeRadial(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::MakeRadial(center, center.fX, data.fColors,
data.fPos, data.fCount, tm);
}
static sk_sp<SkShader> MakeSweep(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::MakeSweep(center.fX, center.fY, data.fColors, data.fPos, data.fCount);
}
static sk_sp<SkShader> Make2Conical(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm) {
SkPoint center0, center1;
center0.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
center1.set(SkScalarInterp(pts[0].fX, pts[1].fX, SkIntToScalar(3)/5),
SkScalarInterp(pts[0].fY, pts[1].fY, SkIntToScalar(1)/4));
return SkGradientShader::MakeTwoPointConical(
center1, (pts[1].fX - pts[0].fX) / 7,
center0, (pts[1].fX - pts[0].fX) / 2,
data.fColors, data.fPos, data.fCount, tm);
}
static sk_sp<SkShader> Make2ConicalConcentric(const SkPoint pts[2], const GradData& data,
SkShader::TileMode tm) {
SkPoint center;
center.set(SkScalarAve(pts[0].fX, pts[1].fX),
SkScalarAve(pts[0].fY, pts[1].fY));
return SkGradientShader::MakeTwoPointConical(
center, (pts[1].fX - pts[0].fX) / 7,
center, (pts[1].fX - pts[0].fX) / 2,
data.fColors, data.fPos, data.fCount, tm);
}
typedef sk_sp<SkShader> (*GradMaker)(const SkPoint pts[2], const GradData& data, SkShader::TileMode tm);
static const GradMaker gGradMakers[] = {
MakeLinear, MakeRadial, MakeSweep, Make2Conical, Make2ConicalConcentric
};
///////////////////////////////////////////////////////////////////////////////
class GradientsView : public SampleView {
public:
GradientsView() {
this->setBGColor(0xFFDDDDDD);
}
protected:
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Gradients");
return true;
}
return this->INHERITED::onQuery(evt);
}
void onDrawContent(SkCanvas* canvas) override {
SkPoint pts[2] = {
{ 0, 0 },
{ SkIntToScalar(100), SkIntToScalar(100) }
};
SkRect r = { 0, 0, SkIntToScalar(100), SkIntToScalar(100) };
SkPaint paint;
paint.setDither(true);
canvas->save();
canvas->translate(SkIntToScalar(20), SkIntToScalar(10));
for (int tm = 0; tm < SkShader::kTileModeCount; ++tm) {
canvas->save();
for (size_t i = 0; i < SK_ARRAY_COUNT(gGradData); i++) {
canvas->save();
for (size_t j = 0; j < SK_ARRAY_COUNT(gGradMakers); j++) {
paint.setShader(gGradMakers[j](pts, gGradData[i], (SkShader::TileMode)tm));
canvas->drawRect(r, paint);
canvas->translate(0, SkIntToScalar(120));
}
canvas->restore();
canvas->translate(SkIntToScalar(120), 0);
}
canvas->restore();
canvas->translate(SK_ARRAY_COUNT(gGradData)*SkIntToScalar(120), 0);
}
canvas->restore();
canvas->translate(0, SkIntToScalar(370));
if (false) { // avoid bit rot, suppress warning
test_alphagradients(canvas);
}
}
private:
typedef SampleView INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new GradientsView; }
static SkViewRegister reg(MyFactory);
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