skia2/src/core/SkDeviceLooper.cpp
skia.committer@gmail.com 6b00a1ec2a Sanitizing source files in Housekeeper-Nightly
git-svn-id: http://skia.googlecode.com/svn/trunk@10992 2bbb7eff-a529-9590-31e7-b0007b416f81
2013-08-29 07:01:20 +00:00

115 lines
3.4 KiB
C++

/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkDeviceLooper.h"
SkDeviceLooper::SkDeviceLooper(const SkBitmap& base,
const SkRasterClip& rc,
const SkIRect& bounds, bool aa)
: fBaseBitmap(base)
, fBaseRC(rc)
, fDelta(aa ? kAA_Delta : kBW_Delta)
{
// sentinels that next() has not yet been called, and so our mapper functions
// should not be called either.
fCurrBitmap = NULL;
fCurrRC = NULL;
SkIRect bitmapBounds = SkIRect::MakeWH(base.width(), base.height());
if (!fClippedBounds.intersect(bounds, bitmapBounds)) {
fState = kDone_State;
} else if (this->fitsInDelta(bounds)) {
fState = kSimple_State;
} else {
// back up by 1 DX, so that next() will put us in a correct starting
// position.
fCurrOffset.set(fClippedBounds.left() - fDelta,
fClippedBounds.top());
fState = kComplex_State;
}
}
SkDeviceLooper::~SkDeviceLooper() {
}
void SkDeviceLooper::mapRect(SkRect* dst, const SkRect& src) const {
SkASSERT(kDone_State != fState);
SkASSERT(fCurrBitmap);
SkASSERT(fCurrRC);
*dst = src;
dst->offset(SkIntToScalar(-fCurrOffset.fX),
SkIntToScalar(-fCurrOffset.fY));
}
void SkDeviceLooper::mapMatrix(SkMatrix* dst, const SkMatrix& src) const {
SkASSERT(kDone_State != fState);
SkASSERT(fCurrBitmap);
SkASSERT(fCurrRC);
*dst = src;
dst->postTranslate(SkIntToScalar(-fCurrOffset.fX),
SkIntToScalar(-fCurrOffset.fY));
}
bool SkDeviceLooper::computeCurrBitmapAndClip() {
SkASSERT(kComplex_State == fState);
SkIRect r = SkIRect::MakeXYWH(fCurrOffset.x(), fCurrOffset.y(),
fDelta, fDelta);
if (!fBaseBitmap.extractSubset(&fSubsetBitmap, r)) {
fState = kDone_State;
return false;
}
fSubsetBitmap.lockPixels();
fBaseRC.translate(-r.left(), -r.top(), &fSubsetRC);
(void)fSubsetRC.op(SkIRect::MakeWH(fDelta, fDelta), SkRegion::kIntersect_Op);
fCurrBitmap = &fSubsetBitmap;
fCurrRC = &fSubsetRC;
return true;
}
bool SkDeviceLooper::next() {
switch (fState) {
case kDone_State:
// in theory, we should not get called here, since we must have
// previously returned false, but we check anyway.
break;
case kSimple_State:
// first time for simple
if (NULL == fCurrBitmap) {
fCurrBitmap = &fBaseBitmap;
fCurrRC = &fBaseRC;
fCurrOffset.set(0, 0);
return true;
}
// 2nd time for simple, we are done
break;
case kComplex_State:
// need to propogate fCurrOffset through clippedbounds
// left to right, until we wrap around and move down
if (fCurrOffset.x() + fDelta < fClippedBounds.right()) {
fCurrOffset.fX += fDelta;
return this->computeCurrBitmapAndClip();
}
fCurrOffset.fX = fClippedBounds.left();
if (fCurrOffset.y() + fDelta < fClippedBounds.bottom()) {
fCurrOffset.fY += fDelta;
return this->computeCurrBitmapAndClip();
}
break;
}
fState = kDone_State;
return false;
}