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lightning-sunbird  0.9+nobinonly
nsCairoBlender.cpp
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00001 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
00002 /* ***** BEGIN LICENSE BLOCK *****
00003  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
00004  *
00005  * The contents of this file are subject to the Mozilla Public License Version
00006  * 1.1 (the "License"); you may not use this file except in compliance with
00007  * the License. You may obtain a copy of the License at
00008  * http://www.mozilla.org/MPL/
00009  *
00010  * Software distributed under the License is distributed on an "AS IS" basis,
00011  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
00012  * for the specific language governing rights and limitations under the
00013  * License.
00014  *
00015  * The Original Code is mozilla.org code.
00016  *
00017  * The Initial Developer of the Original Code is
00018  * mozilla.org.
00019  * Portions created by the Initial Developer are Copyright (C) 2004
00020  * the Initial Developer. All Rights Reserved.
00021  *
00022  * Contributor(s):
00023  *   Vladimir Vukicevic <vladimir@pobox.com>
00024  *
00025  * Alternatively, the contents of this file may be used under the terms of
00026  * either the GNU General Public License Version 2 or later (the "GPL"), or
00027  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
00028  * in which case the provisions of the GPL or the LGPL are applicable instead
00029  * of those above. If you wish to allow use of your version of this file only
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00033  * and other provisions required by the GPL or the LGPL. If you do not delete
00034  * the provisions above, a recipient may use your version of this file under
00035  * the terms of any one of the MPL, the GPL or the LGPL.
00036  *
00037  * ***** END LICENSE BLOCK ***** */
00038 
00039 #include "nsMemory.h"
00040 
00041 #include "nsCairoBlender.h"
00042 #include "nsCairoDrawingSurface.h"
00043 
00044 NS_IMPL_ISUPPORTS1(nsCairoBlender, nsIBlender)
00045 
00046 nsCairoBlender::nsCairoBlender()
00047     : mCairoDC(nsnull)
00048 {
00049 }
00050 
00051 nsCairoBlender::~nsCairoBlender()
00052 {
00053 }
00054 
00055 NS_IMETHODIMP
00056 nsCairoBlender::Init(nsIDeviceContext *aContext)
00057 {
00058     mCairoDC = NS_STATIC_CAST(nsCairoDeviceContext*, aContext);
00059     return NS_OK;
00060 }
00061 
00062 NS_IMETHODIMP
00063 nsCairoBlender::Blend(PRInt32 aSX, PRInt32 aSY, PRInt32 aWidth, PRInt32 aHeight,
00064                       nsIDrawingSurface* aSrc, nsIDrawingSurface* aDest,
00065                       PRInt32 aDX, PRInt32 aDY,
00066                       float aSrcOpacity,
00067                       nsIDrawingSurface* aSecondSrc,
00068                       nscolor aSrcBackColor, nscolor aSecondSrcBackColor)
00069 {
00070     nsCairoDrawingSurface *cSrc = NS_STATIC_CAST(nsCairoDrawingSurface *, aSrc);
00071     nsCairoDrawingSurface *cDest = NS_STATIC_CAST(nsCairoDrawingSurface *, aDest);
00072 
00073     cairo_surface_t *src_surf = cSrc->GetCairoSurface();
00074     cairo_surface_t *dst_surf = cDest->GetCairoSurface();
00075 
00076     cairo_t *cairo = cairo_create();
00077     cairo_set_target_surface(cairo, dst_surf);
00078 
00079     cairo_rectangle (cairo, aDX, aDY, aWidth, aHeight);
00080     cairo_clip (cairo);
00081 
00082     PRUint32 srcWidth, srcHeight;
00083     aSrc->GetDimensions(&srcWidth, &srcHeight);
00084 
00085     cairo_translate (cairo, double(aDX - aSX), double(aDY - aSY));
00086     cairo_show_surface (cairo, src_surf, srcWidth, srcHeight);
00087 
00088     cairo_destroy (cairo);
00089 
00090     return NS_OK;
00091 }
00092 
00093 NS_IMETHODIMP
00094 nsCairoBlender::Blend(PRInt32 aSX, PRInt32 aSY, PRInt32 aWidth, PRInt32 aHeight,
00095                       nsIRenderingContext *aSrc, nsIRenderingContext *aDest,
00096                       PRInt32 aDX, PRInt32 aDY, float aSrcOpacity,
00097                       nsIRenderingContext *aSecondSrc, nscolor aSrcBackColor,
00098                       nscolor aSecondSrcBackColor)
00099 {
00100     nsIDrawingSurface* srcSurface, *destSurface, *secondSrcSurface = nsnull;
00101     aSrc->GetDrawingSurface(&srcSurface);
00102     aDest->GetDrawingSurface(&destSurface);
00103     if (aSecondSrc != nsnull)
00104         aSecondSrc->GetDrawingSurface(&secondSrcSurface);
00105     return Blend(aSX, aSY, aWidth, aHeight, srcSurface, destSurface,
00106                  aDX, aDY, aSrcOpacity, secondSrcSurface, aSrcBackColor,
00107                  aSecondSrcBackColor);
00108 }
00109 
00110 
00111 NS_IMETHODIMP
00112 nsCairoBlender::GetAlphas(const nsRect& aRect, nsIDrawingSurface* aBlack,
00113                           nsIDrawingSurface* aWhite, PRUint8** aAlphas)
00114 {
00115     *aAlphas = (PRUint8*) nsMemory::Alloc(aRect.width * aRect.height);
00116     NS_ENSURE_TRUE(*aAlphas, NS_ERROR_OUT_OF_MEMORY);
00117 
00118     memset(*aAlphas, 0, aRect.width * aRect.height);
00119     return NS_OK;
00120 }