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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 "SkTestImageFilters.h"
#include "SkCanvas.h"
#include "SkDevice.h"
#include "SkReadBuffer.h"
#include "SkWriteBuffer.h"
// Simple helper canvas that "takes ownership" of the provided device, so that
// when this canvas goes out of scope, so will its device. Could be replaced
// with the following:
//
// SkCanvas canvas(device);
// SkAutoTUnref<SkBaseDevice> aur(device);
//
class OwnDeviceCanvas : public SkCanvas {
public:
OwnDeviceCanvas(SkBaseDevice* device) : SkCanvas(device) {
SkSafeUnref(device);
}
};
///////////////////////////////////////////////////////////////////////////////
bool SkDownSampleImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
const Context&,
SkBitmap* result, SkIPoint*) const {
SkScalar scale = fScale;
if (scale > SK_Scalar1 || scale <= 0) {
return false;
}
int dstW = SkScalarRoundToInt(src.width() * scale);
int dstH = SkScalarRoundToInt(src.height() * scale);
if (dstW < 1) {
dstW = 1;
}
if (dstH < 1) {
dstH = 1;
}
SkBitmap tmp;
// downsample
{
SkBaseDevice* dev = proxy->createDevice(dstW, dstH);
if (nullptr == dev) {
return false;
}
OwnDeviceCanvas canvas(dev);
SkPaint paint;
paint.setFilterQuality(kLow_SkFilterQuality);
canvas.scale(scale, scale);
canvas.drawBitmap(src, 0, 0, &paint);
tmp = dev->accessBitmap(false);
}
// upscale
{
SkBaseDevice* dev = proxy->createDevice(src.width(), src.height());
if (nullptr == dev) {
return false;
}
OwnDeviceCanvas canvas(dev);
canvas.drawBitmapRect(tmp, SkRect::MakeIWH(src.width(), src.height()), nullptr);
*result = dev->accessBitmap(false);
}
return true;
}
SkFlattenable* SkDownSampleImageFilter::CreateProc(SkReadBuffer& buffer) {
SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1);
return Create(buffer.readScalar(), common.getInput(0));
}
void SkDownSampleImageFilter::flatten(SkWriteBuffer& buffer) const {
this->INHERITED::flatten(buffer);
buffer.writeScalar(fScale);
}
#ifndef SK_IGNORE_TO_STRING
void SkDownSampleImageFilter::toString(SkString* str) const {
str->appendf("SkDownSampleImageFilter: (");
str->append(")");
}
#endif
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