gecko-dev/gfx/2d/PathD2D.h
Lee Salzman b2d67698b9 Bug 1846079 - Ensure pruned point begins first sub-path if necessary. r=aosmond
The Canvas2D specification says that if a path has no active sub-paths, and a
primitive is drawn, that the first point of that primitive becomes the start of
the newly created sub-path that will be created for it.

So if we prune a point when a path has no active sub-paths, and then a new
primitive comes in that does not start with that same point, we risk not
installing the pruned point as the start of that new sub-path.

To solve this, we need to detect if a path has no active sub-paths while
we are building it. This adds PathBuilder::IsActive() to help with that.
Then before we go to add a primitive, we check if there is a pruned point
on a path that is not active yet, and if so, install the correct start
point with a MoveTo.

This also makes IsActive and IsEmpty required so to ensure all our path
implementations behave consistently rather than having any surprising
unimplemented behavior.

Differential Revision: https://phabricator.services.mozilla.com/D184891
2023-07-30 14:31:09 +00:00

120 lines
3.6 KiB
C++

/* -*- 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/. */
#ifndef MOZILLA_GFX_PATHD2D_H_
#define MOZILLA_GFX_PATHD2D_H_
#include <d2d1.h>
#include "2D.h"
namespace mozilla {
namespace gfx {
class PathD2D;
class PathBuilderD2D : public PathBuilder {
public:
MOZ_DECLARE_REFCOUNTED_VIRTUAL_TYPENAME(PathBuilderD2D, override)
PathBuilderD2D(ID2D1GeometrySink* aSink, ID2D1PathGeometry* aGeom,
FillRule aFillRule, BackendType aBackendType)
: mSink(aSink),
mGeometry(aGeom),
mFigureActive(false),
mFillRule(aFillRule),
mBackendType(aBackendType) {}
virtual ~PathBuilderD2D();
virtual void MoveTo(const Point& aPoint);
virtual void LineTo(const Point& aPoint);
virtual void BezierTo(const Point& aCP1, const Point& aCP2,
const Point& aCP3);
virtual void QuadraticBezierTo(const Point& aCP1, const Point& aCP2);
virtual void Close();
virtual void Arc(const Point& aOrigin, Float aRadius, Float aStartAngle,
Float aEndAngle, bool aAntiClockwise = false);
virtual already_AddRefed<Path> Finish();
virtual BackendType GetBackendType() const { return mBackendType; }
ID2D1GeometrySink* GetSink() { return mSink; }
bool IsFigureActive() const { return mFigureActive; }
virtual bool IsActive() const { return IsFigureActive(); }
static already_AddRefed<PathBuilder> Create(FillRule aFillRule);
private:
friend class PathD2D;
void EnsureActive(const Point& aPoint);
RefPtr<ID2D1GeometrySink> mSink;
RefPtr<ID2D1PathGeometry> mGeometry;
bool mFigureActive;
bool mFigureEmpty = true;
FillRule mFillRule;
BackendType mBackendType;
};
class PathD2D : public Path {
public:
MOZ_DECLARE_REFCOUNTED_VIRTUAL_TYPENAME(PathD2D, override)
PathD2D(ID2D1PathGeometry* aGeometry, bool aEndedActive, bool aIsEmpty,
const Point& aEndPoint, FillRule aFillRule, BackendType aBackendType)
: mGeometry(aGeometry),
mEndedActive(aEndedActive),
mIsEmpty(aIsEmpty),
mEndPoint(aEndPoint),
mFillRule(aFillRule),
mBackendType(aBackendType) {}
virtual BackendType GetBackendType() const { return mBackendType; }
virtual already_AddRefed<PathBuilder> CopyToBuilder(FillRule aFillRule) const;
virtual already_AddRefed<PathBuilder> TransformedCopyToBuilder(
const Matrix& aTransform, FillRule aFillRule) const;
virtual bool ContainsPoint(const Point& aPoint,
const Matrix& aTransform) const;
virtual bool StrokeContainsPoint(const StrokeOptions& aStrokeOptions,
const Point& aPoint,
const Matrix& aTransform) const;
virtual Rect GetBounds(const Matrix& aTransform = Matrix()) const;
virtual Rect GetStrokedBounds(const StrokeOptions& aStrokeOptions,
const Matrix& aTransform = Matrix()) const;
virtual void StreamToSink(PathSink* aSink) const;
virtual FillRule GetFillRule() const { return mFillRule; }
bool IsEmpty() const override { return mIsEmpty; }
ID2D1Geometry* GetGeometry() { return mGeometry; }
private:
friend class DrawTargetD2D;
friend class DrawTargetD2D1;
mutable RefPtr<ID2D1PathGeometry> mGeometry;
bool mEndedActive;
bool mIsEmpty;
Point mEndPoint;
FillRule mFillRule;
BackendType mBackendType;
};
} // namespace gfx
} // namespace mozilla
#endif /* MOZILLA_GFX_PATHD2D_H_ */