tenfourfox/gfx/2d/PathSkia.cpp
Cameron Kaiser c9b2922b70 hello FPR
2017-04-19 00:56:45 -07:00

258 lines
6.9 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* 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 "PathSkia.h"
#include <math.h>
#include "DrawTargetSkia.h"
#include "Logging.h"
#include "HelpersSkia.h"
#include "PathHelpers.h"
namespace mozilla {
namespace gfx {
PathBuilderSkia::PathBuilderSkia(const Matrix& aTransform, const SkPath& aPath, FillRule aFillRule)
: mPath(aPath)
{
SkMatrix matrix;
GfxMatrixToSkiaMatrix(aTransform, matrix);
mPath.transform(matrix);
SetFillRule(aFillRule);
}
PathBuilderSkia::PathBuilderSkia(FillRule aFillRule)
{
SetFillRule(aFillRule);
}
void
PathBuilderSkia::SetFillRule(FillRule aFillRule)
{
mFillRule = aFillRule;
if (mFillRule == FillRule::FILL_WINDING) {
mPath.setFillType(SkPath::kWinding_FillType);
} else {
mPath.setFillType(SkPath::kEvenOdd_FillType);
}
}
void
PathBuilderSkia::MoveTo(const Point &aPoint)
{
mPath.moveTo(SkFloatToScalar(aPoint.x), SkFloatToScalar(aPoint.y));
}
void
PathBuilderSkia::LineTo(const Point &aPoint)
{
if (!mPath.countPoints()) {
MoveTo(aPoint);
} else {
mPath.lineTo(SkFloatToScalar(aPoint.x), SkFloatToScalar(aPoint.y));
}
}
void
PathBuilderSkia::BezierTo(const Point &aCP1,
const Point &aCP2,
const Point &aCP3)
{
if (!mPath.countPoints()) {
MoveTo(aCP1);
}
mPath.cubicTo(SkFloatToScalar(aCP1.x), SkFloatToScalar(aCP1.y),
SkFloatToScalar(aCP2.x), SkFloatToScalar(aCP2.y),
SkFloatToScalar(aCP3.x), SkFloatToScalar(aCP3.y));
}
void
PathBuilderSkia::QuadraticBezierTo(const Point &aCP1,
const Point &aCP2)
{
if (!mPath.countPoints()) {
MoveTo(aCP1);
}
mPath.quadTo(SkFloatToScalar(aCP1.x), SkFloatToScalar(aCP1.y),
SkFloatToScalar(aCP2.x), SkFloatToScalar(aCP2.y));
}
void
PathBuilderSkia::Close()
{
mPath.close();
}
void
PathBuilderSkia::Arc(const Point &aOrigin, float aRadius, float aStartAngle,
float aEndAngle, bool aAntiClockwise)
{
ArcToBezier(this, aOrigin, Size(aRadius, aRadius), aStartAngle, aEndAngle, aAntiClockwise);
}
Point
PathBuilderSkia::CurrentPoint() const
{
int pointCount = mPath.countPoints();
if (!pointCount) {
return Point(0, 0);
}
SkPoint point = mPath.getPoint(pointCount - 1);
return Point(SkScalarToFloat(point.fX), SkScalarToFloat(point.fY));
}
already_AddRefed<Path>
PathBuilderSkia::Finish()
{
return MakeAndAddRef<PathSkia>(mPath, mFillRule);
}
void
PathBuilderSkia::AppendPath(const SkPath &aPath)
{
mPath.addPath(aPath);
}
already_AddRefed<PathBuilder>
PathSkia::CopyToBuilder(FillRule aFillRule) const
{
return TransformedCopyToBuilder(Matrix(), aFillRule);
}
already_AddRefed<PathBuilder>
PathSkia::TransformedCopyToBuilder(const Matrix &aTransform, FillRule aFillRule) const
{
return MakeAndAddRef<PathBuilderSkia>(aTransform, mPath, aFillRule);
}
static bool
SkPathContainsPoint(const SkPath& aPath, const Point& aPoint, const Matrix& aTransform)
{
// Skia's SkPath::contains method does not support the inclusive boundary conditions
// required by canvas (bug 831259), so we employ the same workaround as used by Blink.
// First, we scale the path up to the largest coordinates that won't cause precision
// issues (2^15) and consequently also scale larger paths than that down.
// Next, we make a clip region representing the point to be tested and convert the
// path to a region within this clip region.
// If the resulting region is non-empty, then the path should contain the point.
Matrix inverse = aTransform;
inverse.Invert();
SkPoint point = PointToSkPoint(inverse * aPoint);
SkRect bounds = aPath.getBounds();
if (point.fX < bounds.fLeft || point.fY < bounds.fTop ||
point.fX > bounds.fRight || point.fY > bounds.fBottom) {
return false;
}
SkPoint scale = SkPoint::Make(SkMaxScalar(bounds.fRight, -bounds.fLeft),
SkMaxScalar(bounds.fBottom, -bounds.fTop));
if (SkScalarNearlyZero(scale.fX) || SkScalarNearlyZero(scale.fY)) {
return false;
}
scale.set(SkMaxScalar(scale.fX, SkScalarAbs(point.fX) + SK_Scalar1),
SkMaxScalar(scale.fY, SkScalarAbs(point.fY) + SK_Scalar1));
const SkScalar maxCoord = SkIntToScalar(1 << 15);
SkMatrix scaleMatrix;
scaleMatrix.setScale(maxCoord / scale.fX, maxCoord / scale.fY);
SkPath scaledPath(aPath);
scaledPath.transform(scaleMatrix, nullptr);
scaleMatrix.mapPoints(&point, 1);
SkRegion pointClip(SkIRect::MakeXYWH(SkScalarRoundToInt(point.fX) - 1,
SkScalarRoundToInt(point.fY) - 1,
2, 2));
SkRegion pathRegion;
return pathRegion.setPath(scaledPath, pointClip);
}
bool
PathSkia::ContainsPoint(const Point &aPoint, const Matrix &aTransform) const
{
if (!mPath.isFinite()) {
return false;
}
return SkPathContainsPoint(mPath, aPoint, aTransform);
}
bool
PathSkia::StrokeContainsPoint(const StrokeOptions &aStrokeOptions,
const Point &aPoint,
const Matrix &aTransform) const
{
if (!mPath.isFinite()) {
return false;
}
SkPaint paint;
StrokeOptionsToPaint(paint, aStrokeOptions);
SkPath strokePath;
paint.getFillPath(mPath, &strokePath);
return SkPathContainsPoint(strokePath, aPoint, aTransform);
}
Rect
PathSkia::GetBounds(const Matrix &aTransform) const
{
Rect bounds = SkRectToRect(mPath.getBounds());
return aTransform.TransformBounds(bounds);
}
Rect
PathSkia::GetStrokedBounds(const StrokeOptions &aStrokeOptions,
const Matrix &aTransform) const
{
SkPaint paint;
StrokeOptionsToPaint(paint, aStrokeOptions);
SkPath result;
paint.getFillPath(mPath, &result);
Rect bounds = SkRectToRect(result.getBounds());
return aTransform.TransformBounds(bounds);
}
void
PathSkia::StreamToSink(PathSink *aSink) const
{
SkPath::RawIter iter(mPath);
SkPoint points[4];
SkPath::Verb currentVerb;
while ((currentVerb = iter.next(points)) != SkPath::kDone_Verb) {
switch (currentVerb) {
case SkPath::kMove_Verb:
aSink->MoveTo(SkPointToPoint(points[0]));
break;
case SkPath::kLine_Verb:
aSink->LineTo(SkPointToPoint(points[1]));
break;
case SkPath::kCubic_Verb:
aSink->BezierTo(SkPointToPoint(points[1]),
SkPointToPoint(points[2]),
SkPointToPoint(points[3]));
break;
case SkPath::kQuad_Verb:
aSink->QuadraticBezierTo(SkPointToPoint(points[1]),
SkPointToPoint(points[2]));
break;
case SkPath::kClose_Verb:
aSink->Close();
break;
default:
MOZ_ASSERT(false);
// Unexpected verb found in path!
}
}
}
} // namespace gfx
} // namespace mozilla