layout/svg/SVGUseFrame.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "SVGUseFrame.h"
   8
   9 #include "mozilla/PresShell.h"
  10 #include "mozilla/SVGObserverUtils.h"
  11 #include "mozilla/SVGUtils.h"
  12 #include "mozilla/dom/MutationEvent.h"
  13 #include "mozilla/dom/SVGUseElement.h"
  14 #include "nsLayoutUtils.h"
  15
  16 using namespace mozilla::dom;
  17
  18 //----------------------------------------------------------------------
  19 // Implementation
  20
  21 nsIFrame* NS_NewSVGUseFrame(mozilla::PresShell* aPresShell,
  22                             mozilla::ComputedStyle* aStyle) {
  23   return new (aPresShell)
  24       mozilla::SVGUseFrame(aStyle, aPresShell->GetPresContext());
  25 }
  26
  27 namespace mozilla {
  28
  29 NS_IMPL_FRAMEARENA_HELPERS(SVGUseFrame)
  30
  31 //----------------------------------------------------------------------
  32 // nsIFrame methods:
  33
  34 void SVGUseFrame::Init(nsIContent* aContent, nsContainerFrame* aParent,
  35                        nsIFrame* aPrevInFlow) {
  36   NS_ASSERTION(aContent->IsSVGElement(nsGkAtoms::use),
  37                "Content is not an SVG use!");
  38
  39   mHasValidDimensions =
  40       static_cast<SVGUseElement*>(aContent)->HasValidDimensions();
  41
  42   SVGGFrame::Init(aContent, aParent, aPrevInFlow);
  43 }
  44
  45 void SVGUseFrame::DidSetComputedStyle(ComputedStyle* aOldComputedStyle) {
  46   SVGGFrame::DidSetComputedStyle(aOldComputedStyle);
  47
  48   if (!aOldComputedStyle) {
  49     return;
  50   }
  51   const auto* newSVGReset = StyleSVGReset();
  52   const auto* oldSVGReset = aOldComputedStyle->StyleSVGReset();
  53
  54   if (newSVGReset->mX != oldSVGReset->mX ||
  55       newSVGReset->mY != oldSVGReset->mY) {
  56     // make sure our cached transform matrix gets (lazily) updated
  57     mCanvasTM = nullptr;
  58     SVGUtils::ScheduleReflowSVG(this);
  59     SVGUtils::NotifyChildrenOfSVGChange(this, TRANSFORM_CHANGED);
  60   }
  61 }
  62
  63 void SVGUseFrame::DimensionAttributeChanged(bool aHadValidDimensions,
  64                                             bool aAttributeIsUsed) {
  65   bool invalidate = aAttributeIsUsed;
  66   if (mHasValidDimensions != aHadValidDimensions) {
  67     mHasValidDimensions = !mHasValidDimensions;
  68     invalidate = true;
  69   }
  70
  71   if (invalidate) {
  72     nsLayoutUtils::PostRestyleEvent(GetContent()->AsElement(), RestyleHint{0},
  73                                     nsChangeHint_InvalidateRenderingObservers);
  74     SVGUtils::ScheduleReflowSVG(this);
  75   }
  76 }
  77
  78 void SVGUseFrame::HrefChanged() {
  79   nsLayoutUtils::PostRestyleEvent(GetContent()->AsElement(), RestyleHint{0},
  80                                   nsChangeHint_InvalidateRenderingObservers);
  81   SVGUtils::ScheduleReflowSVG(this);
  82 }
  83
  84 //----------------------------------------------------------------------
  85 // ISVGDisplayableFrame methods
  86
  87 void SVGUseFrame::ReflowSVG() {
  88   // We only handle x/y offset here, since any width/height that is in force is
  89   // handled by the SVGOuterSVGFrame for the anonymous <svg> that will be
  90   // created for that purpose.
  91   auto* content = SVGUseElement::FromNode(GetContent());
  92   float x = SVGContentUtils::CoordToFloat(content, StyleSVGReset()->mX,
  93                                           SVGContentUtils::X);
  94   float y = SVGContentUtils::CoordToFloat(content, StyleSVGReset()->mY,
  95                                           SVGContentUtils::Y);
  96   mRect.MoveTo(nsLayoutUtils::RoundGfxRectToAppRect(gfxRect(x, y, 0, 0),
  97                                                     AppUnitsPerCSSPixel())
  98                    .TopLeft());
  99
 100   // If we have a filter, we need to invalidate ourselves because filter
 101   // output can change even if none of our descendants need repainting.
 102   if (StyleEffects()->HasFilters()) {
 103     InvalidateFrame();
 104   }
 105
 106   SVGGFrame::ReflowSVG();
 107 }
 108
 109 void SVGUseFrame::NotifySVGChanged(uint32_t aFlags) {
 110   if (aFlags & COORD_CONTEXT_CHANGED && !(aFlags & TRANSFORM_CHANGED)) {
 111     // Coordinate context changes affect mCanvasTM if we have a
 112     // percentage 'x' or 'y'
 113     if (StyleSVGReset()->mX.HasPercent() || StyleSVGReset()->mY.HasPercent()) {
 114       aFlags |= TRANSFORM_CHANGED;
 115       // Ancestor changes can't affect how we render from the perspective of
 116       // any rendering observers that we may have, so we don't need to
 117       // invalidate them. We also don't need to invalidate ourself, since our
 118       // changed ancestor will have invalidated its entire area, which includes
 119       // our area.
 120       // For perf reasons we call this before calling NotifySVGChanged() below.
 121       SVGUtils::ScheduleReflowSVG(this);
 122     }
 123   }
 124
 125   // We don't remove the TRANSFORM_CHANGED flag here if we have a viewBox or
 126   // non-percentage width/height, since if they're set then they are cloned to
 127   // an anonymous child <svg>, and its SVGInnerSVGFrame will do that.
 128
 129   SVGGFrame::NotifySVGChanged(aFlags);
 130 }
 131
 132 }  // namespace mozilla