diff options
Diffstat (limited to 'layout/svg/CSSClipPathInstance.cpp')
| -rw-r--r-- | layout/svg/CSSClipPathInstance.cpp | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/layout/svg/CSSClipPathInstance.cpp b/layout/svg/CSSClipPathInstance.cpp new file mode 100644 index 0000000000..8fd51b2799 --- /dev/null +++ b/layout/svg/CSSClipPathInstance.cpp @@ -0,0 +1,243 @@ +/* -*- 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/. */ + +// Main header first: +#include "CSSClipPathInstance.h" + +#include "mozilla/dom/SVGElement.h" +#include "mozilla/dom/SVGPathData.h" +#include "mozilla/gfx/2D.h" +#include "mozilla/gfx/PathHelpers.h" +#include "mozilla/ShapeUtils.h" +#include "mozilla/SVGUtils.h" +#include "gfx2DGlue.h" +#include "gfxContext.h" +#include "gfxPlatform.h" +#include "nsCSSRendering.h" +#include "nsIFrame.h" +#include "nsLayoutUtils.h" + +using namespace mozilla::dom; +using namespace mozilla::gfx; + +namespace mozilla { + +/* static*/ +void CSSClipPathInstance::ApplyBasicShapeOrPathClip( + gfxContext& aContext, nsIFrame* aFrame, const gfxMatrix& aTransform) { + RefPtr<Path> path = + CreateClipPathForFrame(aContext.GetDrawTarget(), aFrame, aTransform); + if (!path) { + // This behavior matches |SVGClipPathFrame::ApplyClipPath()|. + // https://www.w3.org/TR/css-masking-1/#ClipPathElement: + // "An empty clipping path will completely clip away the element that had + // the clip-path property applied." + aContext.Clip(Rect()); + return; + } + aContext.Clip(path); +} + +/* static*/ +RefPtr<Path> CSSClipPathInstance::CreateClipPathForFrame( + gfx::DrawTarget* aDt, nsIFrame* aFrame, const gfxMatrix& aTransform) { + const auto& clipPathStyle = aFrame->StyleSVGReset()->mClipPath; + MOZ_ASSERT(clipPathStyle.IsShape() || clipPathStyle.IsBox() || + clipPathStyle.IsPath(), + "This is used with basic-shape, geometry-box, and path() only"); + + CSSClipPathInstance instance(aFrame, clipPathStyle); + + return instance.CreateClipPath(aDt, aTransform); +} + +/* static*/ +bool CSSClipPathInstance::HitTestBasicShapeOrPathClip(nsIFrame* aFrame, + const gfxPoint& aPoint) { + const auto& clipPathStyle = aFrame->StyleSVGReset()->mClipPath; + MOZ_ASSERT(!clipPathStyle.IsNone(), "unexpected none value"); + MOZ_ASSERT(!clipPathStyle.IsUrl(), "unexpected url value"); + + CSSClipPathInstance instance(aFrame, clipPathStyle); + + RefPtr<DrawTarget> drawTarget = + gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget(); + RefPtr<Path> path = instance.CreateClipPath( + drawTarget, SVGUtils::GetCSSPxToDevPxMatrix(aFrame)); + float pixelRatio = float(AppUnitsPerCSSPixel()) / + aFrame->PresContext()->AppUnitsPerDevPixel(); + return path && path->ContainsPoint(ToPoint(aPoint) * pixelRatio, Matrix()); +} + +/* static */ +Maybe<Rect> CSSClipPathInstance::GetBoundingRectForBasicShapeOrPathClip( + nsIFrame* aFrame, const StyleClipPath& aClipPathStyle) { + MOZ_ASSERT(aClipPathStyle.IsShape() || aClipPathStyle.IsBox() || + aClipPathStyle.IsPath()); + + CSSClipPathInstance instance(aFrame, aClipPathStyle); + + RefPtr<DrawTarget> drawTarget = + gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget(); + RefPtr<Path> path = instance.CreateClipPath( + drawTarget, SVGUtils::GetCSSPxToDevPxMatrix(aFrame)); + return path ? Some(path->GetBounds()) : Nothing(); +} + +already_AddRefed<Path> CSSClipPathInstance::CreateClipPath( + DrawTarget* aDrawTarget, const gfxMatrix& aTransform) { + if (mClipPathStyle.IsPath()) { + return CreateClipPathPath(aDrawTarget); + } + + nscoord appUnitsPerDevPixel = + mTargetFrame->PresContext()->AppUnitsPerDevPixel(); + + nsRect r; + if (mClipPathStyle.IsBox()) { + r = nsLayoutUtils::ComputeGeometryBox(mTargetFrame, mClipPathStyle.AsBox()); + } else { + r = nsLayoutUtils::ComputeGeometryBox(mTargetFrame, + mClipPathStyle.AsShape()._1); + } + + gfxRect rr(r.x, r.y, r.width, r.height); + rr.Scale(1.0 / AppUnitsPerCSSPixel()); + rr = aTransform.TransformRect(rr); + rr.Scale(appUnitsPerDevPixel); + rr.Round(); + + r = nsRect(int(rr.x), int(rr.y), int(rr.width), int(rr.height)); + + if (mClipPathStyle.IsBox()) { + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(); + AppendRectToPath(builder, NSRectToRect(r, appUnitsPerDevPixel), true); + return builder->Finish(); + } + + MOZ_ASSERT(mClipPathStyle.IsShape()); + + r = ToAppUnits(r.ToNearestPixels(appUnitsPerDevPixel), appUnitsPerDevPixel); + + const auto& basicShape = *mClipPathStyle.AsShape()._0; + switch (basicShape.tag) { + case StyleBasicShape::Tag::Circle: + return CreateClipPathCircle(aDrawTarget, r); + case StyleBasicShape::Tag::Ellipse: + return CreateClipPathEllipse(aDrawTarget, r); + case StyleBasicShape::Tag::Polygon: + return CreateClipPathPolygon(aDrawTarget, r); + case StyleBasicShape::Tag::Inset: + return CreateClipPathInset(aDrawTarget, r); + break; + default: + MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Unexpected shape type"); + } + // Return an empty Path: + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(); + return builder->Finish(); +} + +already_AddRefed<Path> CSSClipPathInstance::CreateClipPathCircle( + DrawTarget* aDrawTarget, const nsRect& aRefBox) { + const auto& basicShape = *mClipPathStyle.AsShape()._0; + + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(); + + nsPoint center = + ShapeUtils::ComputeCircleOrEllipseCenter(basicShape, aRefBox); + nscoord r = ShapeUtils::ComputeCircleRadius(basicShape, center, aRefBox); + nscoord appUnitsPerDevPixel = + mTargetFrame->PresContext()->AppUnitsPerDevPixel(); + builder->Arc(Point(center.x, center.y) / appUnitsPerDevPixel, + r / appUnitsPerDevPixel, 0, Float(2 * M_PI)); + builder->Close(); + return builder->Finish(); +} + +already_AddRefed<Path> CSSClipPathInstance::CreateClipPathEllipse( + DrawTarget* aDrawTarget, const nsRect& aRefBox) { + const auto& basicShape = *mClipPathStyle.AsShape()._0; + + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(); + + nsPoint center = + ShapeUtils::ComputeCircleOrEllipseCenter(basicShape, aRefBox); + nsSize radii = ShapeUtils::ComputeEllipseRadii(basicShape, center, aRefBox); + nscoord appUnitsPerDevPixel = + mTargetFrame->PresContext()->AppUnitsPerDevPixel(); + EllipseToBezier(builder.get(), + Point(center.x, center.y) / appUnitsPerDevPixel, + Size(radii.width, radii.height) / appUnitsPerDevPixel); + builder->Close(); + return builder->Finish(); +} + +already_AddRefed<Path> CSSClipPathInstance::CreateClipPathPolygon( + DrawTarget* aDrawTarget, const nsRect& aRefBox) { + const auto& basicShape = *mClipPathStyle.AsShape()._0; + auto fillRule = basicShape.AsPolygon().fill == StyleFillRule::Nonzero + ? FillRule::FILL_WINDING + : FillRule::FILL_EVEN_ODD; + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(fillRule); + + nsTArray<nsPoint> vertices = + ShapeUtils::ComputePolygonVertices(basicShape, aRefBox); + if (vertices.IsEmpty()) { + MOZ_ASSERT_UNREACHABLE( + "ComputePolygonVertices() should've given us some vertices!"); + } else { + nscoord appUnitsPerDevPixel = + mTargetFrame->PresContext()->AppUnitsPerDevPixel(); + builder->MoveTo(NSPointToPoint(vertices[0], appUnitsPerDevPixel)); + for (size_t i = 1; i < vertices.Length(); ++i) { + builder->LineTo(NSPointToPoint(vertices[i], appUnitsPerDevPixel)); + } + } + builder->Close(); + return builder->Finish(); +} + +already_AddRefed<Path> CSSClipPathInstance::CreateClipPathInset( + DrawTarget* aDrawTarget, const nsRect& aRefBox) { + const auto& basicShape = *mClipPathStyle.AsShape()._0; + + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(); + + nscoord appUnitsPerDevPixel = + mTargetFrame->PresContext()->AppUnitsPerDevPixel(); + + const nsRect insetRect = ShapeUtils::ComputeInsetRect(basicShape, aRefBox); + const Rect insetRectPixels = NSRectToRect(insetRect, appUnitsPerDevPixel); + nscoord appUnitsRadii[8]; + + if (ShapeUtils::ComputeInsetRadii(basicShape, aRefBox, insetRect, + appUnitsRadii)) { + RectCornerRadii corners; + nsCSSRendering::ComputePixelRadii(appUnitsRadii, appUnitsPerDevPixel, + &corners); + + AppendRoundedRectToPath(builder, insetRectPixels, corners, true); + } else { + AppendRectToPath(builder, insetRectPixels, true); + } + return builder->Finish(); +} + +already_AddRefed<Path> CSSClipPathInstance::CreateClipPathPath( + DrawTarget* aDrawTarget) { + const auto& path = mClipPathStyle.AsPath(); + + RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder( + path.fill == StyleFillRule::Nonzero ? FillRule::FILL_WINDING + : FillRule::FILL_EVEN_ODD); + float scale = float(AppUnitsPerCSSPixel()) / + mTargetFrame->PresContext()->AppUnitsPerDevPixel(); + return SVGPathData::BuildPath(path.path._0.AsSpan(), builder, + StyleStrokeLinecap::Butt, 0.0, scale); +} + +} // namespace mozilla |