gecko-dev/layout/svg/nsCSSClipPathInstance.cpp
Ting-Yu Lin a080cb68d1 Bug 1311244 Part 1 - Use nsPoint type for center in nsCSSClipPathInstance. r=dbaron
|center| should be of nsPoint type since all the arguments of
ComputeObjectAnchorPoint() uses nsPoint and nsSize. We should only convert
center to Point (which is an an UnknownUnits type) for APIs requiring Point
type.

MozReview-Commit-ID: EDrQGPUZp6m

--HG--
extra : rebase_source : a5494f969dcb08c139af076e95584502f46f0b9e
2017-01-06 16:35:00 +08:00

275 lines
10 KiB
C++

/* -*- Mode: C++; tab-width: 2; 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/. */
// Main header first:
#include "nsCSSClipPathInstance.h"
#include "gfx2DGlue.h"
#include "gfxPlatform.h"
#include "mozilla/dom/SVGSVGElement.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/PathHelpers.h"
#include "nsCSSRendering.h"
#include "nsIFrame.h"
#include "nsRenderingContext.h"
#include "nsRuleNode.h"
#include "nsSVGElement.h"
#include "nsSVGUtils.h"
#include "nsSVGViewBox.h"
using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::gfx;
/* static*/ void
nsCSSClipPathInstance::ApplyBasicShapeClip(gfxContext& aContext,
nsIFrame* aFrame)
{
auto& clipPathStyle = aFrame->StyleSVGReset()->mClipPath;
#ifdef DEBUG
StyleShapeSourceType type = clipPathStyle.GetType();
MOZ_ASSERT(type == StyleShapeSourceType::Shape ||
type == StyleShapeSourceType::Box,
"This function is used with basic-shape and geometry-box only.");
#endif
nsCSSClipPathInstance instance(aFrame, clipPathStyle);
aContext.NewPath();
RefPtr<Path> path = instance.CreateClipPath(aContext.GetDrawTarget());
aContext.SetPath(path);
aContext.Clip();
}
/* static*/ bool
nsCSSClipPathInstance::HitTestBasicShapeClip(nsIFrame* aFrame,
const gfxPoint& aPoint)
{
auto& clipPathStyle = aFrame->StyleSVGReset()->mClipPath;
StyleShapeSourceType type = clipPathStyle.GetType();
MOZ_ASSERT(type != StyleShapeSourceType::None, "unexpected none value");
// In the future nsCSSClipPathInstance may handle <clipPath> references as
// well. For the time being return early.
if (type == StyleShapeSourceType::URL) {
return false;
}
nsCSSClipPathInstance instance(aFrame, clipPathStyle);
RefPtr<DrawTarget> drawTarget =
gfxPlatform::GetPlatform()->ScreenReferenceDrawTarget();
RefPtr<Path> path = instance.CreateClipPath(drawTarget);
float pixelRatio = float(nsPresContext::AppUnitsPerCSSPixel()) /
aFrame->PresContext()->AppUnitsPerDevPixel();
return path->ContainsPoint(ToPoint(aPoint) * pixelRatio, Matrix());
}
already_AddRefed<Path>
nsCSSClipPathInstance::CreateClipPath(DrawTarget* aDrawTarget)
{
nsRect r =
nsLayoutUtils::ComputeGeometryBox(mTargetFrame,
mClipPathStyle.GetReferenceBox());
if (mClipPathStyle.GetType() != StyleShapeSourceType::Shape) {
// TODO Clip to border-radius/reference box if no shape
// was specified.
RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder();
return builder->Finish();
}
nscoord appUnitsPerDevPixel =
mTargetFrame->PresContext()->AppUnitsPerDevPixel();
r = ToAppUnits(r.ToNearestPixels(appUnitsPerDevPixel), appUnitsPerDevPixel);
StyleBasicShape* basicShape = mClipPathStyle.GetBasicShape();
switch (basicShape->GetShapeType()) {
case StyleBasicShapeType::Circle:
return CreateClipPathCircle(aDrawTarget, r);
case StyleBasicShapeType::Ellipse:
return CreateClipPathEllipse(aDrawTarget, r);
case StyleBasicShapeType::Polygon:
return CreateClipPathPolygon(aDrawTarget, r);
case StyleBasicShapeType::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();
}
static void
EnumerationToLength(nscoord& aCoord, StyleShapeRadius aType,
nscoord aCenter, nscoord aPosMin, nscoord aPosMax)
{
nscoord dist1 = abs(aPosMin - aCenter);
nscoord dist2 = abs(aPosMax - aCenter);
switch (aType) {
case StyleShapeRadius::FarthestSide:
aCoord = dist1 > dist2 ? dist1 : dist2;
break;
case StyleShapeRadius::ClosestSide:
aCoord = dist1 > dist2 ? dist2 : dist1;
break;
}
}
already_AddRefed<Path>
nsCSSClipPathInstance::CreateClipPathCircle(DrawTarget* aDrawTarget,
const nsRect& aRefBox)
{
StyleBasicShape* basicShape = mClipPathStyle.GetBasicShape();
RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder();
nsPoint topLeft, anchor;
nsSize size = nsSize(aRefBox.width, aRefBox.height);
nsImageRenderer::ComputeObjectAnchorPoint(basicShape->GetPosition(),
size, size,
&topLeft, &anchor);
nsPoint center(anchor.x + aRefBox.x, anchor.y + aRefBox.y);
const nsTArray<nsStyleCoord>& coords = basicShape->Coordinates();
MOZ_ASSERT(coords.Length() == 1, "wrong number of arguments");
nscoord r = 0;
if (coords[0].GetUnit() == eStyleUnit_Enumerated) {
const auto styleShapeRadius = coords[0].GetEnumValue<StyleShapeRadius>();
nscoord horizontal, vertical;
EnumerationToLength(horizontal, styleShapeRadius,
center.x, aRefBox.x, aRefBox.x + aRefBox.width);
EnumerationToLength(vertical, styleShapeRadius,
center.y, aRefBox.y, aRefBox.y + aRefBox.height);
if (styleShapeRadius == StyleShapeRadius::FarthestSide) {
r = horizontal > vertical ? horizontal : vertical;
} else {
r = horizontal < vertical ? horizontal : vertical;
}
} else {
// We resolve percent <shape-radius> value for circle() as defined here:
// https://drafts.csswg.org/css-shapes/#funcdef-circle
double referenceLength =
SVGContentUtils::ComputeNormalizedHypotenuse(aRefBox.width,
aRefBox.height);
r = nsRuleNode::ComputeCoordPercentCalc(coords[0],
NSToCoordRound(referenceLength));
}
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>
nsCSSClipPathInstance::CreateClipPathEllipse(DrawTarget* aDrawTarget,
const nsRect& aRefBox)
{
StyleBasicShape* basicShape = mClipPathStyle.GetBasicShape();
RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder();
nsPoint topLeft, anchor;
nsSize size = nsSize(aRefBox.width, aRefBox.height);
nsImageRenderer::ComputeObjectAnchorPoint(basicShape->GetPosition(),
size, size,
&topLeft, &anchor);
nsPoint center(anchor.x + aRefBox.x, anchor.y + aRefBox.y);
const nsTArray<nsStyleCoord>& coords = basicShape->Coordinates();
MOZ_ASSERT(coords.Length() == 2, "wrong number of arguments");
nscoord rx = 0, ry = 0;
if (coords[0].GetUnit() == eStyleUnit_Enumerated) {
EnumerationToLength(rx, coords[0].GetEnumValue<StyleShapeRadius>(),
center.x, aRefBox.x, aRefBox.x + aRefBox.width);
} else {
rx = nsRuleNode::ComputeCoordPercentCalc(coords[0], aRefBox.width);
}
if (coords[1].GetUnit() == eStyleUnit_Enumerated) {
EnumerationToLength(ry, coords[1].GetEnumValue<StyleShapeRadius>(),
center.y, aRefBox.y, aRefBox.y + aRefBox.height);
} else {
ry = nsRuleNode::ComputeCoordPercentCalc(coords[1], aRefBox.height);
}
nscoord appUnitsPerDevPixel =
mTargetFrame->PresContext()->AppUnitsPerDevPixel();
EllipseToBezier(builder.get(),
Point(center.x, center.y) / appUnitsPerDevPixel,
Size(rx, ry) / appUnitsPerDevPixel);
builder->Close();
return builder->Finish();
}
already_AddRefed<Path>
nsCSSClipPathInstance::CreateClipPathPolygon(DrawTarget* aDrawTarget,
const nsRect& aRefBox)
{
StyleBasicShape* basicShape = mClipPathStyle.GetBasicShape();
const nsTArray<nsStyleCoord>& coords = basicShape->Coordinates();
MOZ_ASSERT(coords.Length() % 2 == 0 &&
coords.Length() >= 2, "wrong number of arguments");
FillRule fillRule = basicShape->GetFillRule() == StyleFillRule::Nonzero ?
FillRule::FILL_WINDING : FillRule::FILL_EVEN_ODD;
RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder(fillRule);
nscoord x = nsRuleNode::ComputeCoordPercentCalc(coords[0], aRefBox.width);
nscoord y = nsRuleNode::ComputeCoordPercentCalc(coords[1], aRefBox.height);
nscoord appUnitsPerDevPixel =
mTargetFrame->PresContext()->AppUnitsPerDevPixel();
builder->MoveTo(Point(aRefBox.x + x, aRefBox.y + y) / appUnitsPerDevPixel);
for (size_t i = 2; i < coords.Length(); i += 2) {
x = nsRuleNode::ComputeCoordPercentCalc(coords[i], aRefBox.width);
y = nsRuleNode::ComputeCoordPercentCalc(coords[i + 1], aRefBox.height);
builder->LineTo(Point(aRefBox.x + x, aRefBox.y + y) / appUnitsPerDevPixel);
}
builder->Close();
return builder->Finish();
}
already_AddRefed<Path>
nsCSSClipPathInstance::CreateClipPathInset(DrawTarget* aDrawTarget,
const nsRect& aRefBox)
{
StyleBasicShape* basicShape = mClipPathStyle.GetBasicShape();
const nsTArray<nsStyleCoord>& coords = basicShape->Coordinates();
MOZ_ASSERT(coords.Length() == 4, "wrong number of arguments");
RefPtr<PathBuilder> builder = aDrawTarget->CreatePathBuilder();
nscoord appUnitsPerDevPixel =
mTargetFrame->PresContext()->AppUnitsPerDevPixel();
nsMargin inset(nsRuleNode::ComputeCoordPercentCalc(coords[0], aRefBox.height),
nsRuleNode::ComputeCoordPercentCalc(coords[1], aRefBox.width),
nsRuleNode::ComputeCoordPercentCalc(coords[2], aRefBox.height),
nsRuleNode::ComputeCoordPercentCalc(coords[3], aRefBox.width));
nsRect insetRect(aRefBox);
insetRect.Deflate(inset);
const Rect insetRectPixels = NSRectToRect(insetRect, appUnitsPerDevPixel);
const nsStyleCorners& radius = basicShape->GetRadius();
nscoord appUnitsRadii[8];
if (nsIFrame::ComputeBorderRadii(radius, insetRect.Size(), aRefBox.Size(),
Sides(), appUnitsRadii)) {
RectCornerRadii corners;
nsCSSRendering::ComputePixelRadii(appUnitsRadii,
appUnitsPerDevPixel, &corners);
AppendRoundedRectToPath(builder, insetRectPixels, corners, true);
} else {
AppendRectToPath(builder, insetRectPixels, true);
}
return builder->Finish();
}