layout/svg/base/src/nsSVGGFrame.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is the Mozilla SVG project.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Crocodile Clips Ltd..
  19  * Portions created by the Initial Developer are Copyright (C) 2001
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Alex Fritze <alex.fritze@crocodile-clips.com> (original author)
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "nsIDOMSVGTransformable.h"
  40 #include "nsSVGGFrame.h"
  41 #include "nsIFrame.h"
  42 #include "nsSVGMatrix.h"
  43 #include "nsGkAtoms.h"
  44 #include "nsSVGUtils.h"
  45 #include "nsISVGValueUtils.h"
  46 #include "nsSVGGraphicElement.h"
  47
  48 //----------------------------------------------------------------------
  49 // Implementation
  50
  51 nsIFrame*
  52 NS_NewSVGGFrame(nsIPresShell* aPresShell, nsIContent* aContent, nsStyleContext* aContext)
  53 {
  54   nsCOMPtr<nsIDOMSVGTransformable> transformable = do_QueryInterface(aContent);
  55   if (!transformable) {
  56     NS_ERROR("Can't create frame. The element doesn't support the right interface\n");
  57     return nsnull;
  58   }
  59
  60   return new (aPresShell) nsSVGGFrame(aContext);
  61 }
  62
  63 nsIAtom *
  64 nsSVGGFrame::GetType() const
  65 {
  66   return nsGkAtoms::svgGFrame;
  67 }
  68
  69 //----------------------------------------------------------------------
  70 // nsISVGChildFrame methods
  71
  72 void
  73 nsSVGGFrame::NotifySVGChanged(PRUint32 aFlags)
  74 {
  75   if (aFlags & TRANSFORM_CHANGED) {
  76     // make sure our cached transform matrix gets (lazily) updated
  77     mCanvasTM = nsnull;
  78   }
  79
  80   nsSVGGFrameBase::NotifySVGChanged(aFlags);
  81 }
  82
  83 already_AddRefed<nsIDOMSVGMatrix>
  84 nsSVGGFrame::GetCanvasTM()
  85 {
  86   if (!GetMatrixPropagation()) {
  87     nsIDOMSVGMatrix *retval;
  88     NS_NewSVGMatrix(&retval);
  89     return retval;
  90   }
  91
  92   if (!mCanvasTM) {
  93     // get our parent's tm and append local transforms (if any):
  94     NS_ASSERTION(mParent, "null parent");
  95     nsSVGContainerFrame *containerFrame = static_cast<nsSVGContainerFrame*>
  96                                                      (mParent);
  97     nsCOMPtr<nsIDOMSVGMatrix> parentTM = containerFrame->GetCanvasTM();
  98     NS_ASSERTION(parentTM, "null TM");
  99
 100     // got the parent tm, now check for local tm:
 101     nsSVGGraphicElement *element =
 102       static_cast<nsSVGGraphicElement*>(mContent);
 103     nsCOMPtr<nsIDOMSVGMatrix> localTM = element->GetLocalTransformMatrix();
 104
 105     if (localTM)
 106       parentTM->Multiply(localTM, getter_AddRefs(mCanvasTM));
 107     else
 108       mCanvasTM = parentTM;
 109   }
 110
 111   nsIDOMSVGMatrix* retval = mCanvasTM.get();
 112   NS_IF_ADDREF(retval);
 113   return retval;
 114 }
 115
 116 NS_IMETHODIMP
 117 nsSVGGFrame::AttributeChanged(PRInt32         aNameSpaceID,
 118                               nsIAtom*        aAttribute,
 119                               PRInt32         aModType)
 120 {
 121   if (aNameSpaceID == kNameSpaceID_None &&
 122       aAttribute == nsGkAtoms::transform) {
 123     // make sure our cached transform matrix gets (lazily) updated
 124     mCanvasTM = nsnull;
 125
 126     nsSVGUtils::NotifyChildrenOfSVGChange(this, TRANSFORM_CHANGED);
 127   }
 128
 129   return NS_OK;
 130 }