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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 "SkBlurMaskFilter.h"
#include "SkCamera.h"
#include "SkColorFilter.h"
#include "SkColorPriv.h"
#include "SkDevice.h"
#include "SkGradientShader.h"
#include "SkImageDecoder.h"
#include "SkInterpolator.h"
#include "SkMaskFilter.h"
#include "SkPath.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkTime.h"
#include "SkTypeface.h"
#include "SkUtils.h"
#include "SkKey.h"
#include "SkXfermode.h"
#include "SkDrawFilter.h"
static void make_paint(SkPaint* paint, const SkMatrix& localMatrix) {
SkColor colors[] = { 0, SK_ColorWHITE };
SkPoint pts[] = { { 0, 0 }, { 0, SK_Scalar1*20 } };
SkShader* s = SkGradientShader::CreateLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode,
0, &localMatrix);
paint->setShader(s)->unref();
paint->setXfermodeMode(SkXfermode::kDstIn_Mode);
}
static void dump_layers(const char label[], SkCanvas* canvas) {
SkDebugf("Dump Layers(%s)\n", label);
SkCanvas::LayerIter iter(canvas, true);
int index = 0;
while (!iter.done()) {
SkImageInfo info = iter.device()->imageInfo();
const SkIRect& clip = iter.clip().getBounds();
SkDebugf("Layer[%d] bitmap [%d %d] X=%d Y=%d clip=[%d %d %d %d] alpha=%d\n", index++,
info.width(), info.height(), iter.x(), iter.y(),
clip.fLeft, clip.fTop, clip.fRight, clip.fBottom,
iter.paint().getAlpha());
iter.next();
}
}
// test drawing with strips of fading gradient above and below
static void test_fade(SkCanvas* canvas) {
SkAutoCanvasRestore ar(canvas, true);
SkRect r;
SkPaint p;
p.setAlpha(0x88);
SkAutoCanvasRestore ar2(canvas, false);
// create the layers
r.set(0, 0, SkIntToScalar(100), SkIntToScalar(100));
canvas->clipRect(r);
r.fBottom = SkIntToScalar(20);
canvas->saveLayer(&r, nullptr);
r.fTop = SkIntToScalar(80);
r.fBottom = SkIntToScalar(100);
canvas->saveLayer(&r, nullptr);
// now draw the "content"
if (true) {
r.set(0, 0, SkIntToScalar(100), SkIntToScalar(100));
canvas->saveLayerAlpha(&r, 0x80);
SkPaint p;
p.setColor(SK_ColorRED);
p.setAntiAlias(true);
canvas->drawOval(r, p);
dump_layers("inside layer alpha", canvas);
canvas->restore();
} else {
r.set(0, 0, SkIntToScalar(100), SkIntToScalar(100));
SkPaint p;
p.setColor(SK_ColorRED);
p.setAntiAlias(true);
canvas->drawOval(r, p);
}
// return;
dump_layers("outside layer alpha", canvas);
// now apply an effect
SkMatrix m;
m.setScale(SK_Scalar1, -SK_Scalar1);
m.postTranslate(0, SkIntToScalar(100));
SkPaint paint;
make_paint(&paint, m);
r.set(0, 0, SkIntToScalar(100), SkIntToScalar(20));
// SkDebugf("--------- draw top grad\n");
canvas->drawRect(r, paint);
r.fTop = SkIntToScalar(80);
r.fBottom = SkIntToScalar(100);
// SkDebugf("--------- draw bot grad\n");
canvas->drawRect(r, paint);
}
class RedFilter : public SkDrawFilter {
public:
bool filter(SkPaint* p, SkDrawFilter::Type) override {
fColor = p->getColor();
if (fColor == SK_ColorRED) {
p->setColor(SK_ColorGREEN);
}
return true;
}
private:
SkColor fColor;
};
class LayersView : public SkView {
public:
LayersView() {}
protected:
// overrides from SkEventSink
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "Layers");
return true;
}
return this->INHERITED::onQuery(evt);
}
void drawBG(SkCanvas* canvas) {
canvas->drawColor(SK_ColorGRAY);
}
void onDraw(SkCanvas* canvas) override {
this->drawBG(canvas);
if (true) {
SkRect r;
r.set(SkIntToScalar(0), SkIntToScalar(0),
SkIntToScalar(220), SkIntToScalar(120));
SkPaint p;
canvas->saveLayer(&r, &p);
canvas->drawColor(0xFFFF0000);
p.setAlpha(0); // or 0
p.setXfermodeMode(SkXfermode::kSrc_Mode);
canvas->drawOval(r, p);
canvas->restore();
return;
}
if (false) {
SkRect r;
r.set(SkIntToScalar(0), SkIntToScalar(0),
SkIntToScalar(220), SkIntToScalar(120));
SkPaint p;
p.setAlpha(0x88);
p.setAntiAlias(true);
if (true) {
canvas->saveLayer(&r, &p);
p.setColor(0xFFFF0000);
canvas->drawOval(r, p);
canvas->restore();
}
p.setColor(0xFF0000FF);
r.offset(SkIntToScalar(20), SkIntToScalar(50));
canvas->drawOval(r, p);
}
if (false) {
SkPaint p;
p.setAlpha(0x88);
p.setAntiAlias(true);
canvas->translate(SkIntToScalar(300), 0);
SkRect r;
r.set(SkIntToScalar(0), SkIntToScalar(0),
SkIntToScalar(220), SkIntToScalar(60));
canvas->saveLayer(&r, &p);
r.set(SkIntToScalar(0), SkIntToScalar(0),
SkIntToScalar(220), SkIntToScalar(120));
p.setColor(SK_ColorBLUE);
canvas->drawOval(r, p);
canvas->restore();
return;
}
test_fade(canvas);
}
SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override {
this->inval(nullptr);
return this->INHERITED::onFindClickHandler(x, y, modi);
}
bool onClick(Click* click) override {
return this->INHERITED::onClick(click);
}
virtual bool handleKey(SkKey) {
this->inval(nullptr);
return true;
}
private:
typedef SkView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new LayersView; }
static SkViewRegister reg(MyFactory);
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