layout/svg/base/src/nsSVGAFrame.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
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  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  * Robert Longson.
  19  * Portions created by the Initial Developer are Copyright (C) 2007
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Robert Longson <longsonr@gmail.com> (original author)
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  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
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  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "nsSVGTSpanFrame.h"
  40 #include "nsISVGGlyphFragmentNode.h"
  41 #include "nsSVGGraphicElement.h"
  42 #include "nsSVGMatrix.h"
  43 #include "nsIDOMSVGAElement.h"
  44 #include "nsSVGUtils.h"
  45
  46 // <a> elements can contain text. nsSVGGlyphFrames expect to have
  47 // a class derived from nsSVGTextContainerFrame as a parent. We
  48 // also need something that implements nsISVGGlyphFragmentNode to get
  49 // the text DOM to work.
  50
  51 typedef nsSVGTSpanFrame nsSVGAFrameBase;
  52
  53 class nsSVGAFrame : public nsSVGAFrameBase
  54 {
  55   friend nsIFrame*
  56   NS_NewSVGAFrame(nsIPresShell* aPresShell, nsIContent* aContent,
  57                   nsStyleContext* aContext);
  58 protected:
  59   nsSVGAFrame(nsStyleContext* aContext) :
  60     nsSVGAFrameBase(aContext) {}
  61
  62 public:
  63   // nsIFrame:
  64   NS_IMETHOD  AttributeChanged(PRInt32         aNameSpaceID,
  65                                nsIAtom*        aAttribute,
  66                                PRInt32         aModType);
  67
  68   /**
  69    * Get the "type" of the frame
  70    *
  71    * @see nsGkAtoms::svgAFrame
  72    */
  73   virtual nsIAtom* GetType() const;
  74
  75 #ifdef DEBUG
  76   NS_IMETHOD GetFrameName(nsAString& aResult) const
  77   {
  78     return MakeFrameName(NS_LITERAL_STRING("SVGA"), aResult);
  79   }
  80 #endif
  81   // nsISVGChildFrame interface:
  82   virtual void NotifySVGChanged(PRUint32 aFlags);
  83
  84   // nsSVGContainerFrame methods:
  85   virtual already_AddRefed<nsIDOMSVGMatrix> GetCanvasTM();
  86
  87 private:
  88   nsCOMPtr<nsIDOMSVGMatrix> mCanvasTM;
  89 };
  90
  91 //----------------------------------------------------------------------
  92 // Implementation
  93
  94 nsIFrame*
  95 NS_NewSVGAFrame(nsIPresShell* aPresShell, nsIContent* aContent, nsStyleContext* aContext)
  96 {
  97   nsCOMPtr<nsIDOMSVGAElement> elem = do_QueryInterface(aContent);
  98   if (!elem) {
  99     NS_ERROR("Trying to construct an SVGAFrame for a "
 100              "content element that doesn't support the right interfaces");
 101     return nsnull;
 102   }
 103
 104   return new (aPresShell) nsSVGAFrame(aContext);
 105 }
 106
 107 //----------------------------------------------------------------------
 108 // nsIFrame methods
 109
 110 NS_IMETHODIMP
 111 nsSVGAFrame::AttributeChanged(PRInt32         aNameSpaceID,
 112                               nsIAtom*        aAttribute,
 113                               PRInt32         aModType)
 114 {
 115   if (aNameSpaceID != kNameSpaceID_None)
 116     return NS_OK;
 117
 118   if (aAttribute == nsGkAtoms::transform) {
 119     // transform has changed
 120
 121     // make sure our cached transform matrix gets (lazily) updated
 122     mCanvasTM = nsnull;
 123
 124     nsSVGUtils::NotifyChildrenOfSVGChange(this, TRANSFORM_CHANGED);
 125   }
 126
 127  return NS_OK;
 128 }
 129
 130 nsIAtom *
 131 nsSVGAFrame::GetType() const
 132 {
 133   return nsGkAtoms::svgAFrame;
 134 }
 135
 136 //----------------------------------------------------------------------
 137 // nsISVGChildFrame methods
 138
 139 void
 140 nsSVGAFrame::NotifySVGChanged(PRUint32 aFlags)
 141 {
 142   if (aFlags & TRANSFORM_CHANGED) {
 143     // make sure our cached transform matrix gets (lazily) updated
 144     mCanvasTM = nsnull;
 145   }
 146
 147   nsSVGAFrameBase::NotifySVGChanged(aFlags);
 148 }
 149
 150 //----------------------------------------------------------------------
 151 // nsSVGContainerFrame methods:
 152
 153 already_AddRefed<nsIDOMSVGMatrix>
 154 nsSVGAFrame::GetCanvasTM()
 155 {
 156   if (!GetMatrixPropagation()) {
 157     nsIDOMSVGMatrix *retval;
 158     NS_NewSVGMatrix(&retval);
 159     return retval;
 160   }
 161
 162   if (!mCanvasTM) {
 163     // get our parent's tm and append local transforms (if any):
 164     NS_ASSERTION(mParent, "null parent");
 165     nsSVGContainerFrame *containerFrame = static_cast<nsSVGContainerFrame*>
 166                                                      (mParent);
 167     nsCOMPtr<nsIDOMSVGMatrix> parentTM = containerFrame->GetCanvasTM();
 168     NS_ASSERTION(parentTM, "null TM");
 169
 170     // got the parent tm, now check for local tm:
 171     nsSVGGraphicElement *element =
 172       static_cast<nsSVGGraphicElement*>(mContent);
 173     nsCOMPtr<nsIDOMSVGMatrix> localTM = element->GetLocalTransformMatrix();
 174
 175     if (localTM)
 176       parentTM->Multiply(localTM, getter_AddRefs(mCanvasTM));
 177     else
 178       mCanvasTM = parentTM;
 179   }
 180
 181   nsIDOMSVGMatrix* retval = mCanvasTM.get();
 182   NS_IF_ADDREF(retval);
 183   return retval;
 184 }