gecko-dev/gfx/thebes/gfxCachedTempSurface.cpp
2011-10-17 10:59:28 -04:00

142 lines
4.5 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Corporation code.
*
* The Initial Developer of the Original Code is Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Karl Tomlinson <karlt+@karlt.net>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "gfxCachedTempSurface.h"
#include "gfxContext.h"
class CachedSurfaceExpirationTracker :
public nsExpirationTracker<gfxCachedTempSurface,2> {
public:
// With K = 2, this means that surfaces will be released when they are not
// used for 1-2 seconds.
enum { TIMEOUT_MS = 1000 };
CachedSurfaceExpirationTracker()
: nsExpirationTracker<gfxCachedTempSurface,2>(TIMEOUT_MS) {}
~CachedSurfaceExpirationTracker() {
AgeAllGenerations();
}
virtual void NotifyExpired(gfxCachedTempSurface* aSurface) {
RemoveObject(aSurface);
aSurface->Expire();
}
static void MarkSurfaceUsed(gfxCachedTempSurface* aSurface)
{
if (aSurface->GetExpirationState()->IsTracked()) {
sExpirationTracker->MarkUsed(aSurface);
return;
}
if (!sExpirationTracker) {
sExpirationTracker = new CachedSurfaceExpirationTracker();
}
sExpirationTracker->AddObject(aSurface);
}
static void RemoveSurface(gfxCachedTempSurface* aSurface)
{
if (!sExpirationTracker)
return;
if (aSurface->GetExpirationState()->IsTracked()) {
sExpirationTracker->RemoveObject(aSurface);
}
if (sExpirationTracker->IsEmpty()) {
delete sExpirationTracker;
sExpirationTracker = nsnull;
}
}
private:
static CachedSurfaceExpirationTracker* sExpirationTracker;
};
CachedSurfaceExpirationTracker*
CachedSurfaceExpirationTracker::sExpirationTracker = nsnull;
gfxCachedTempSurface::~gfxCachedTempSurface()
{
CachedSurfaceExpirationTracker::RemoveSurface(this);
}
already_AddRefed<gfxContext>
gfxCachedTempSurface::Get(gfxASurface::gfxContentType aContentType,
const gfxRect& aRect,
gfxASurface* aSimilarTo)
{
if (mSurface) {
/* Verify the current buffer is valid for this purpose */
if (mSize.width < aRect.width || mSize.height < aRect.height
|| mSurface->GetContentType() != aContentType) {
mSurface = nsnull;
} else {
NS_ASSERTION(mType == aSimilarTo->GetType(),
"Unexpected surface type change");
}
}
bool cleared = false;
if (!mSurface) {
mSize = gfxIntSize(PRInt32(ceil(aRect.width)), PRInt32(ceil(aRect.height)));
mSurface = aSimilarTo->CreateSimilarSurface(aContentType, mSize);
if (!mSurface)
return nsnull;
cleared = true;
#ifdef DEBUG
mType = aSimilarTo->GetType();
#endif
}
mSurface->SetDeviceOffset(-aRect.TopLeft());
nsRefPtr<gfxContext> ctx = new gfxContext(mSurface);
ctx->Rectangle(aRect);
ctx->Clip();
if (!cleared && aContentType != gfxASurface::CONTENT_COLOR) {
ctx->SetOperator(gfxContext::OPERATOR_CLEAR);
ctx->Paint();
ctx->SetOperator(gfxContext::OPERATOR_OVER);
}
CachedSurfaceExpirationTracker::MarkSurfaceUsed(this);
return ctx.forget();
}