skia2/samplecode/SampleDrawBitmap.cpp

85 lines
2.4 KiB
C++
Raw Normal View History

/*
* 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 "SkShader.h"
#include "SkUtils.h"
#include "SkDevice.h"
static void create_bitmap(SkBitmap* bitmap) {
const int W = 100;
const int H = 100;
bitmap->setConfig(SkBitmap::kARGB_8888_Config, W, H);
bitmap->allocPixels();
SkCanvas canvas(*bitmap);
canvas.drawColor(SK_ColorRED);
SkPaint paint;
paint.setColor(SK_ColorBLUE);
canvas.drawCircle(SkIntToScalar(W)/2, SkIntToScalar(H)/2, SkIntToScalar(W)/2, paint);
}
class DrawBitmapView : public SampleView {
SkPath fPath;
public:
DrawBitmapView() {}
protected:
// overrides from SkEventSink
virtual bool onQuery(SkEvent* evt) {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "DrawBitmap");
return true;
}
return this->INHERITED::onQuery(evt);
}
virtual void onDrawContent(SkCanvas* canvas) {
SkBitmap bitmap;
create_bitmap(&bitmap);
int x = bitmap.width() / 2;
int y = bitmap.height() / 2;
SkBitmap subset;
bitmap.extractSubset(&subset, SkIRect::MakeXYWH(x, y, x, y));
canvas->translate(SkIntToScalar(20), SkIntToScalar(20));
canvas->drawBitmap(bitmap, 0, 0);
canvas->drawBitmap(subset, 0, 0);
// Now do the same but with a device bitmap as source image
SkRefPtr<SkDevice> primaryDevice(canvas->getDevice());
SkRefPtr<SkDevice> secondDevice(canvas->createCompatibleDevice(
SkBitmap::kARGB_8888_Config, bitmap.width(),
bitmap.height(), true));
secondDevice->unref();
SkCanvas secondCanvas(secondDevice.get());
secondCanvas.writePixels(bitmap, 0, 0);
SkBitmap deviceBitmap = secondDevice->accessBitmap(false);
SkBitmap deviceSubset;
deviceBitmap.extractSubset(&deviceSubset,
SkIRect::MakeXYWH(x, y, x, y));
canvas->translate(SkIntToScalar(120), SkIntToScalar(0));
canvas->drawBitmap(deviceBitmap, 0, 0);
canvas->drawBitmap(deviceSubset, 0, 0);
}
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new DrawBitmapView; }
static SkViewRegister reg(MyFactory);