dom/svg/SVGCircleElement.cpp
author violet <violet.bugreport@gmail.com>
Thu, 16 May 2019 00:53:45 +0000
changeset 532849 e864696f6cf80910479dce91eed090a6455a4e2f
parent 532847 7bc3bff991c45a6e9caefe5fb4791aeba7d29256
child 532859 1624c5a319174b9c850b3183a95d8bbefb051f41
permissions -rw-r--r--
Bug 1383650 - Add conversion utilities to get CSS counterpart of SVG unit and AttrEnum r=longsonr We need some utilities to convert SVG unit and attrenum to CSS unit and property id. This is useful when we need to pass parsed geometry property directly to CSS. Differential Revision: https://phabricator.services.mozilla.com/D30777

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "ComputedStyle.h"
#include "mozilla/dom/SVGCircleElement.h"
#include "mozilla/gfx/2D.h"
#include "nsGkAtoms.h"
#include "mozilla/dom/SVGCircleElementBinding.h"
#include "mozilla/dom/SVGLengthBinding.h"
#include "SVGGeometryProperty.h"

NS_IMPL_NS_NEW_SVG_ELEMENT(Circle)

using namespace mozilla::gfx;

namespace mozilla {
namespace dom {

JSObject* SVGCircleElement::WrapNode(JSContext* aCx,
                                     JS::Handle<JSObject*> aGivenProto) {
  return SVGCircleElement_Binding::Wrap(aCx, this, aGivenProto);
}

SVGElement::LengthInfo SVGCircleElement::sLengthInfo[3] = {
    {nsGkAtoms::cx, 0, SVGLength_Binding::SVG_LENGTHTYPE_NUMBER,
     SVGContentUtils::X},
    {nsGkAtoms::cy, 0, SVGLength_Binding::SVG_LENGTHTYPE_NUMBER,
     SVGContentUtils::Y},
    {nsGkAtoms::r, 0, SVGLength_Binding::SVG_LENGTHTYPE_NUMBER,
     SVGContentUtils::XY}};

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

SVGCircleElement::SVGCircleElement(
    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
    : SVGCircleElementBase(std::move(aNodeInfo)) {}

bool SVGCircleElement::IsAttributeMapped(const nsAtom* aAttribute) const {
  return IsInLengthInfo(aAttribute, sLengthInfo) ||
         SVGCircleElementBase::IsAttributeMapped(aAttribute);
}

namespace SVGT = SVGGeometryProperty::Tags;

//----------------------------------------------------------------------
// nsINode methods

NS_IMPL_ELEMENT_CLONE_WITH_INIT(SVGCircleElement)

//----------------------------------------------------------------------

already_AddRefed<DOMSVGAnimatedLength> SVGCircleElement::Cx() {
  return mLengthAttributes[ATTR_CX].ToDOMAnimatedLength(this);
}

already_AddRefed<DOMSVGAnimatedLength> SVGCircleElement::Cy() {
  return mLengthAttributes[ATTR_CY].ToDOMAnimatedLength(this);
}

already_AddRefed<DOMSVGAnimatedLength> SVGCircleElement::R() {
  return mLengthAttributes[ATTR_R].ToDOMAnimatedLength(this);
}

//----------------------------------------------------------------------
// SVGElement methods

/* virtual */
bool SVGCircleElement::HasValidDimensions() const {
  float r;

  MOZ_ASSERT(GetPrimaryFrame());
  SVGGeometryProperty::ResolveAll<SVGT::R>(this, &r);
  return r > 0;
}

SVGElement::LengthAttributesInfo SVGCircleElement::GetLengthInfo() {
  return LengthAttributesInfo(mLengthAttributes, sLengthInfo,
                              ArrayLength(sLengthInfo));
}

//----------------------------------------------------------------------
// SVGGeometryElement methods

bool SVGCircleElement::GetGeometryBounds(
    Rect* aBounds, const StrokeOptions& aStrokeOptions,
    const Matrix& aToBoundsSpace, const Matrix* aToNonScalingStrokeSpace) {
  float x, y, r;

  MOZ_ASSERT(GetPrimaryFrame());
  SVGGeometryProperty::ResolveAll<SVGT::Cx, SVGT::Cy, SVGT::R>(this, &x, &y,
                                                               &r);

  if (r <= 0.f) {
    // Rendering of the element is disabled
    *aBounds = Rect(aToBoundsSpace.TransformPoint(Point(x, y)), Size());
    return true;
  }

  if (aToBoundsSpace.IsRectilinear()) {
    // Optimize the case where we can treat the circle as a rectangle and
    // still get tight bounds.
    if (aStrokeOptions.mLineWidth > 0.f) {
      if (aToNonScalingStrokeSpace) {
        if (aToNonScalingStrokeSpace->IsRectilinear()) {
          MOZ_ASSERT(!aToNonScalingStrokeSpace->IsSingular());
          Rect userBounds(x - r, y - r, 2 * r, 2 * r);
          SVGContentUtils::RectilinearGetStrokeBounds(
              userBounds, aToBoundsSpace, *aToNonScalingStrokeSpace,
              aStrokeOptions.mLineWidth, aBounds);
          return true;
        }
        return false;
      }
      r += aStrokeOptions.mLineWidth / 2.f;
    }
    Rect rect(x - r, y - r, 2 * r, 2 * r);
    *aBounds = aToBoundsSpace.TransformBounds(rect);
    return true;
  }

  return false;
}

already_AddRefed<Path> SVGCircleElement::BuildPath(PathBuilder* aBuilder) {
  float x, y, r;
  MOZ_ASSERT(GetPrimaryFrame());
  SVGGeometryProperty::ResolveAll<SVGT::Cx, SVGT::Cy, SVGT::R>(this, &x, &y,
                                                               &r);

  if (r <= 0.0f) {
    return nullptr;
  }

  aBuilder->Arc(Point(x, y), r, 0, Float(2 * M_PI));

  return aBuilder->Finish();
}

bool SVGCircleElement::IsLengthChangedViaCSS(const ComputedStyle& aNewStyle,
                                             const ComputedStyle& aOldStyle) {
  auto *newSVGReset = aNewStyle.StyleSVGReset(),
       *oldSVGReset = aOldStyle.StyleSVGReset();

  return newSVGReset->mCx != oldSVGReset->mCx ||
         newSVGReset->mCy != oldSVGReset->mCy ||
         newSVGReset->mR != oldSVGReset->mR;
}

nsCSSPropertyID SVGCircleElement::GetCSSPropertyIdForAttrEnum(
    uint8_t aAttrEnum) {
  switch (aAttrEnum) {
    case ATTR_CX:
      return eCSSProperty_cx;
    case ATTR_CY:
      return eCSSProperty_cy;
    case ATTR_R:
      return eCSSProperty_r;
    default:
      MOZ_ASSERT_UNREACHABLE("Unknown attr enum");
      return eCSSProperty_UNKNOWN;
  }
}

}  // namespace dom
}  // namespace mozilla