1 files changed, 298 insertions, 0 deletions
diff --git a/dom/svg/SVGGeometryElement.cpp b/dom/svg/SVGGeometryElement.cpp
new file mode 100644
index 0000000000..d012a911b8
--- /dev/null
+++ b/dom/svg/SVGGeometryElement.cpp
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+/* -*- 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 "SVGGeometryElement.h"
+
+#include "DOMSVGPoint.h"
+#include "gfxPlatform.h"
+#include "nsCOMPtr.h"
+#include "SVGAnimatedLength.h"
+#include "SVGCircleElement.h"
+#include "SVGEllipseElement.h"
+#include "SVGGeometryProperty.h"
+#include "SVGPathElement.h"
+#include "SVGRectElement.h"
+#include "mozilla/dom/DOMPointBinding.h"
+#include "mozilla/dom/SVGLengthBinding.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/StaticPrefs_layout.h"
+#include "mozilla/SVGContentUtils.h"
+
+using namespace mozilla::gfx;
+
+namespace mozilla::dom {
+
+SVGElement::NumberInfo SVGGeometryElement::sNumberInfo = {nsGkAtoms::pathLength,
+                                                          0};
+
+//----------------------------------------------------------------------
+// Implementation
+
+SVGGeometryElement::SVGGeometryElement(
+    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
+    : SVGGeometryElementBase(std::move(aNodeInfo)) {}
+
+SVGElement::NumberAttributesInfo SVGGeometryElement::GetNumberInfo() {
+  return NumberAttributesInfo(&mPathLength, &sNumberInfo, 1);
+}
+
+void SVGGeometryElement::AfterSetAttr(int32_t aNamespaceID, nsAtom* aName,
+                                      const nsAttrValue* aValue,
+                                      const nsAttrValue* aOldValue,
+                                      nsIPrincipal* aSubjectPrincipal,
+                                      bool aNotify) {
+  if (mCachedPath && aNamespaceID == kNameSpaceID_None &&
+      AttributeDefinesGeometry(aName)) {
+    mCachedPath = nullptr;
+  }
+  return SVGGeometryElementBase::AfterSetAttr(
+      aNamespaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
+}
+
+bool SVGGeometryElement::AttributeDefinesGeometry(const nsAtom* aName) {
+  if (aName == nsGkAtoms::pathLength) {
+    return true;
+  }
+
+  // Check for SVGAnimatedLength attribute
+  LengthAttributesInfo info = GetLengthInfo();
+  for (uint32_t i = 0; i < info.mCount; i++) {
+    if (aName == info.mInfos[i].mName) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool SVGGeometryElement::GeometryDependsOnCoordCtx() {
+  // Check the SVGAnimatedLength attribute
+  LengthAttributesInfo info =
+      const_cast<SVGGeometryElement*>(this)->GetLengthInfo();
+  for (uint32_t i = 0; i < info.mCount; i++) {
+    if (info.mValues[i].IsPercentage()) {
+      return true;
+    }
+  }
+  return false;
+}
+
+bool SVGGeometryElement::IsMarkable() { return false; }
+
+void SVGGeometryElement::GetMarkPoints(nsTArray<SVGMark>* aMarks) {}
+
+already_AddRefed<Path> SVGGeometryElement::GetOrBuildPath(
+    const DrawTarget* aDrawTarget, FillRule aFillRule) {
+  // We only cache the path if it matches the backend used for screen painting,
+  // and it's not a capturing drawtarget. A capturing DT might start using the
+  // the Path object on a different thread (OMTP), and we might have a data race
+  // if we keep a handle to it.
+  bool cacheable = aDrawTarget->GetBackendType() ==
+                   gfxPlatform::GetPlatform()->GetDefaultContentBackend();
+
+  if (cacheable && mCachedPath && mCachedPath->GetFillRule() == aFillRule &&
+      aDrawTarget->GetBackendType() == mCachedPath->GetBackendType()) {
+    RefPtr<Path> path(mCachedPath);
+    return path.forget();
+  }
+  RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(aFillRule);
+  RefPtr<Path> path = BuildPath(builder);
+  if (cacheable) {
+    mCachedPath = path;
+  }
+  return path.forget();
+}
+
+already_AddRefed<Path> SVGGeometryElement::GetOrBuildPathForMeasuring() {
+  RefPtr<DrawTarget> drawTarget =
+      gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget();
+  FillRule fillRule = mCachedPath ? mCachedPath->GetFillRule() : GetFillRule();
+  return GetOrBuildPath(drawTarget, fillRule);
+}
+
+// This helper is currently identical to GetOrBuildPathForMeasuring.
+// We keep it a separate method because for length measuring purpose,
+// fillRule isn't really needed. Derived class (e.g. SVGPathElement)
+// may override GetOrBuildPathForMeasuring() to ignore fillRule. And
+// GetOrBuildPathForMeasuring() itself may be modified in the future.
+already_AddRefed<Path> SVGGeometryElement::GetOrBuildPathForHitTest() {
+  RefPtr<DrawTarget> drawTarget =
+      gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget();
+  FillRule fillRule = mCachedPath ? mCachedPath->GetFillRule() : GetFillRule();
+  return GetOrBuildPath(drawTarget, fillRule);
+}
+
+bool SVGGeometryElement::IsGeometryChangedViaCSS(
+    ComputedStyle const& aNewStyle, ComputedStyle const& aOldStyle) const {
+  nsAtom* name = NodeInfo()->NameAtom();
+  if (name == nsGkAtoms::rect) {
+    return SVGRectElement::IsLengthChangedViaCSS(aNewStyle, aOldStyle);
+  }
+  if (name == nsGkAtoms::circle) {
+    return SVGCircleElement::IsLengthChangedViaCSS(aNewStyle, aOldStyle);
+  }
+  if (name == nsGkAtoms::ellipse) {
+    return SVGEllipseElement::IsLengthChangedViaCSS(aNewStyle, aOldStyle);
+  }
+  if (name == nsGkAtoms::path) {
+    return SVGPathElement::IsDPropertyChangedViaCSS(aNewStyle, aOldStyle);
+  }
+  return false;
+}
+
+FillRule SVGGeometryElement::GetFillRule() {
+  FillRule fillRule =
+      FillRule::FILL_WINDING;  // Equivalent to StyleFillRule::Nonzero
+
+  bool res = SVGGeometryProperty::DoForComputedStyle(
+      this, [&](const ComputedStyle* s) {
+        const auto* styleSVG = s->StyleSVG();
+
+        MOZ_ASSERT(styleSVG->mFillRule == StyleFillRule::Nonzero ||
+                   styleSVG->mFillRule == StyleFillRule::Evenodd);
+
+        if (styleSVG->mFillRule == StyleFillRule::Evenodd) {
+          fillRule = FillRule::FILL_EVEN_ODD;
+        }
+      });
+
+  if (!res) {
+    NS_WARNING("Couldn't get ComputedStyle for content in GetFillRule");
+  }
+
+  return fillRule;
+}
+
+static Point GetPointFrom(const DOMPointInit& aPoint) {
+  return Point(aPoint.mX, aPoint.mY);
+}
+
+bool SVGGeometryElement::IsPointInFill(const DOMPointInit& aPoint) {
+  // d is a presentation attribute, so make sure style is up to date:
+  FlushStyleIfNeeded();
+
+  RefPtr<Path> path = GetOrBuildPathForHitTest();
+  if (!path) {
+    return false;
+  }
+
+  auto point = GetPointFrom(aPoint);
+  return path->ContainsPoint(point, {});
+}
+
+bool SVGGeometryElement::IsPointInStroke(const DOMPointInit& aPoint) {
+  // stroke-* attributes and the d attribute are presentation attributes, so we
+  // flush the layout before building the path.
+  if (nsCOMPtr<Document> doc = GetComposedDoc()) {
+    doc->FlushPendingNotifications(FlushType::Layout);
+  }
+
+  RefPtr<Path> path = GetOrBuildPathForHitTest();
+  if (!path) {
+    return false;
+  }
+
+  auto point = GetPointFrom(aPoint);
+  bool res = false;
+  SVGGeometryProperty::DoForComputedStyle(this, [&](const ComputedStyle* s) {
+    // Per spec, we should take vector-effect into account.
+    if (s->StyleSVGReset()->HasNonScalingStroke()) {
+      auto mat = SVGContentUtils::GetCTM(this, true);
+      if (mat.HasNonTranslation()) {
+        // We have non-scaling-stroke as well as a non-translation transform.
+        // We should transform the path first then apply the stroke on the
+        // transformed path to preserve the stroke-width.
+        RefPtr<PathBuilder> builder = path->TransformedCopyToBuilder(mat);
+
+        path = builder->Finish();
+        point = mat.TransformPoint(point);
+      }
+    }
+
+    SVGContentUtils::AutoStrokeOptions strokeOptions;
+    SVGContentUtils::GetStrokeOptions(&strokeOptions, this, s, nullptr);
+
+    res = path->StrokeContainsPoint(strokeOptions, point, {});
+  });
+
+  return res;
+}
+
+float SVGGeometryElement::GetTotalLengthForBinding() {
+  // d is a presentation attribute, so make sure style is up to date:
+  FlushStyleIfNeeded();
+  return GetTotalLength();
+}
+
+already_AddRefed<DOMSVGPoint> SVGGeometryElement::GetPointAtLength(
+    float distance, ErrorResult& rv) {
+  // d is a presentation attribute, so make sure style is up to date:
+  FlushStyleIfNeeded();
+  RefPtr<Path> path = GetOrBuildPathForMeasuring();
+  if (!path) {
+    rv.ThrowInvalidStateError("No path available for measuring");
+    return nullptr;
+  }
+
+  return do_AddRef(new DOMSVGPoint(path->ComputePointAtLength(
+      clamped(distance, 0.f, path->ComputeLength()))));
+}
+
+float SVGGeometryElement::GetPathLengthScale(PathLengthScaleForType aFor) {
+  MOZ_ASSERT(aFor == eForTextPath || aFor == eForStroking, "Unknown enum");
+  if (mPathLength.IsExplicitlySet()) {
+    float authorsPathLengthEstimate = mPathLength.GetAnimValue();
+    if (authorsPathLengthEstimate >= 0) {
+      RefPtr<Path> path = GetOrBuildPathForMeasuring();
+      if (!path) {
+        // The path is empty or invalid so its length must be zero and
+        // we know that 0 / authorsPathLengthEstimate = 0.
+        return 0.0;
+      }
+      if (aFor == eForTextPath) {
+        // For textPath, a transform on the referenced path affects the
+        // textPath layout, so when calculating the actual path length
+        // we need to take that into account.
+        gfxMatrix matrix = PrependLocalTransformsTo(gfxMatrix());
+        if (!matrix.IsIdentity()) {
+          RefPtr<PathBuilder> builder =
+              path->TransformedCopyToBuilder(ToMatrix(matrix));
+          path = builder->Finish();
+        }
+      }
+      return path->ComputeLength() / authorsPathLengthEstimate;
+    }
+  }
+  return 1.0;
+}
+
+already_AddRefed<DOMSVGAnimatedNumber> SVGGeometryElement::PathLength() {
+  return mPathLength.ToDOMAnimatedNumber(this);
+}
+
+float SVGGeometryElement::GetTotalLength() {
+  RefPtr<Path> flat = GetOrBuildPathForMeasuring();
+  return flat ? flat->ComputeLength() : 0.f;
+}
+
+void SVGGeometryElement::FlushStyleIfNeeded() {
+  // Note: we still can set d property on other elements which don't have d
+  // attribute, but we don't look at the d property on them, so here we only
+  // care about the element with d attribute, i.e. SVG path element.
+  if (GetPathDataAttrName() != nsGkAtoms::d) {
+    return;
+  }
+
+  RefPtr<Document> doc = GetComposedDoc();
+  if (!doc) {
+    return;
+  }
+
+  doc->FlushPendingNotifications(FlushType::Style);
+}
+
+}  // namespace mozilla::dom