gecko/layout/svg/base/src/nsSVGGFrame.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * 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/
 *
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 * 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 the Mozilla SVG project.
 *
 * The Initial Developer of the Original Code is
 * Crocodile Clips Ltd..
 * Portions created by the Initial Developer are Copyright (C) 2001
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Alex Fritze <alex.fritze@crocodile-clips.com> (original author)
 *
 * 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"),
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#include "nsIDOMSVGTransformable.h"
#include "nsSVGGFrame.h"
#include "nsIFrame.h"
#include "nsSVGMatrix.h"
#include "nsGkAtoms.h"
#include "nsSVGUtils.h"
#include "nsSVGGraphicElement.h"

//----------------------------------------------------------------------
// Implementation

nsIFrame*
NS_NewSVGGFrame(nsIPresShell* aPresShell, nsIContent* aContent, nsStyleContext* aContext)
{  
  nsCOMPtr<nsIDOMSVGTransformable> transformable = do_QueryInterface(aContent);
  if (!transformable) {
    NS_ERROR("Can't create frame. The element doesn't support the right interface\n");
    return nsnull;
  }

  return new (aPresShell) nsSVGGFrame(aContext);
}

nsIAtom *
nsSVGGFrame::GetType() const
{
  return nsGkAtoms::svgGFrame;
}

//----------------------------------------------------------------------
// nsISVGChildFrame methods

void
nsSVGGFrame::NotifySVGChanged(PRUint32 aFlags)
{
  if (aFlags & TRANSFORM_CHANGED) {
    // make sure our cached transform matrix gets (lazily) updated
    mCanvasTM = nsnull;
  }

  nsSVGGFrameBase::NotifySVGChanged(aFlags);
}

already_AddRefed<nsIDOMSVGMatrix>
nsSVGGFrame::GetCanvasTM()
{
  if (!GetMatrixPropagation()) {
    nsIDOMSVGMatrix *retval;
    NS_NewSVGMatrix(&retval);
    return retval;
  }

  if (!mCanvasTM) {
    // get our parent's tm and append local transforms (if any):
    NS_ASSERTION(mParent, "null parent");
    nsSVGContainerFrame *containerFrame = static_cast<nsSVGContainerFrame*>
                                                     (mParent);
    nsCOMPtr<nsIDOMSVGMatrix> parentTM = containerFrame->GetCanvasTM();
    NS_ASSERTION(parentTM, "null TM");

    // got the parent tm, now check for local tm:
    nsSVGGraphicElement *element =
      static_cast<nsSVGGraphicElement*>(mContent);
    nsCOMPtr<nsIDOMSVGMatrix> localTM = element->GetLocalTransformMatrix();

    if (localTM)
      parentTM->Multiply(localTM, getter_AddRefs(mCanvasTM));
    else
      mCanvasTM = parentTM;
  }

  nsIDOMSVGMatrix* retval = mCanvasTM.get();
  NS_IF_ADDREF(retval);
  return retval;
}

NS_IMETHODIMP
nsSVGGFrame::AttributeChanged(PRInt32         aNameSpaceID,
                              nsIAtom*        aAttribute,
                              PRInt32         aModType)
{
  if (aNameSpaceID == kNameSpaceID_None &&
      aAttribute == nsGkAtoms::transform) {
    // make sure our cached transform matrix gets (lazily) updated
    mCanvasTM = nsnull;

    nsSVGUtils::NotifyChildrenOfSVGChange(this, TRANSFORM_CHANGED);
  }
  
  return NS_OK;
}