gecko-dev/layout/svg/nsSVGGradientFrame.cpp

679 lines
22 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 "nsSVGGradientFrame.h"
#include <algorithm>
// Keep others in (case-insensitive) order:
#include "gfxPattern.h"
#include "mozilla/dom/SVGGradientElement.h"
#include "mozilla/dom/SVGStopElement.h"
#include "nsContentUtils.h"
#include "nsSVGEffects.h"
#include "nsSVGAnimatedTransformList.h"
// XXX Tight coupling with content classes ahead!
using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::gfx;
//----------------------------------------------------------------------
// Helper classes
class MOZ_RAII nsSVGGradientFrame::AutoGradientReferencer
{
public:
explicit AutoGradientReferencer(nsSVGGradientFrame *aFrame
MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
: mFrame(aFrame)
{
MOZ_GUARD_OBJECT_NOTIFIER_INIT;
// Reference loops should normally be detected in advance and handled, so
// we're not expecting to encounter them here
MOZ_ASSERT(!mFrame->mLoopFlag, "Undetected reference loop!");
mFrame->mLoopFlag = true;
}
~AutoGradientReferencer() {
mFrame->mLoopFlag = false;
}
private:
nsSVGGradientFrame *mFrame;
MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
};
//----------------------------------------------------------------------
// Implementation
nsSVGGradientFrame::nsSVGGradientFrame(nsStyleContext* aContext)
: nsSVGPaintServerFrame(aContext)
, mLoopFlag(false)
, mNoHRefURI(false)
{
}
//----------------------------------------------------------------------
// nsIFrame methods:
nsresult
nsSVGGradientFrame::AttributeChanged(int32_t aNameSpaceID,
nsIAtom* aAttribute,
int32_t aModType)
{
if (aNameSpaceID == kNameSpaceID_None &&
(aAttribute == nsGkAtoms::gradientUnits ||
aAttribute == nsGkAtoms::gradientTransform ||
aAttribute == nsGkAtoms::spreadMethod)) {
nsSVGEffects::InvalidateDirectRenderingObservers(this);
} else if ((aNameSpaceID == kNameSpaceID_XLink ||
aNameSpaceID == kNameSpaceID_None) &&
aAttribute == nsGkAtoms::href) {
// Blow away our reference, if any
Properties().Delete(nsSVGEffects::HrefAsPaintingProperty());
mNoHRefURI = false;
// And update whoever references us
nsSVGEffects::InvalidateDirectRenderingObservers(this);
}
return nsSVGPaintServerFrame::AttributeChanged(aNameSpaceID,
aAttribute, aModType);
}
//----------------------------------------------------------------------
uint16_t
nsSVGGradientFrame::GetEnumValue(uint32_t aIndex, nsIContent *aDefault)
{
const nsSVGEnum& thisEnum =
static_cast<dom::SVGGradientElement*>(mContent)->mEnumAttributes[aIndex];
if (thisEnum.IsExplicitlySet())
return thisEnum.GetAnimValue();
AutoGradientReferencer gradientRef(this);
nsSVGGradientFrame *next = GetReferencedGradientIfNotInUse();
return next ? next->GetEnumValue(aIndex, aDefault) :
static_cast<dom::SVGGradientElement*>(aDefault)->
mEnumAttributes[aIndex].GetAnimValue();
}
uint16_t
nsSVGGradientFrame::GetGradientUnits()
{
// This getter is called every time the others are called - maybe cache it?
return GetEnumValue(dom::SVGGradientElement::GRADIENTUNITS);
}
uint16_t
nsSVGGradientFrame::GetSpreadMethod()
{
return GetEnumValue(dom::SVGGradientElement::SPREADMETHOD);
}
const nsSVGAnimatedTransformList*
nsSVGGradientFrame::GetGradientTransformList(nsIContent* aDefault)
{
nsSVGAnimatedTransformList *thisTransformList =
static_cast<dom::SVGGradientElement*>(mContent)->GetAnimatedTransformList();
if (thisTransformList && thisTransformList->IsExplicitlySet())
return thisTransformList;
AutoGradientReferencer gradientRef(this);
nsSVGGradientFrame *next = GetReferencedGradientIfNotInUse();
return next ? next->GetGradientTransformList(aDefault) :
static_cast<const dom::SVGGradientElement*>(aDefault)
->mGradientTransform.get();
}
gfxMatrix
nsSVGGradientFrame::GetGradientTransform(nsIFrame *aSource,
const gfxRect *aOverrideBounds)
{
gfxMatrix bboxMatrix;
uint16_t gradientUnits = GetGradientUnits();
if (gradientUnits != SVG_UNIT_TYPE_USERSPACEONUSE) {
NS_ASSERTION(gradientUnits == SVG_UNIT_TYPE_OBJECTBOUNDINGBOX,
"Unknown gradientUnits type");
// objectBoundingBox is the default anyway
gfxRect bbox =
aOverrideBounds ? *aOverrideBounds : nsSVGUtils::GetBBox(aSource);
bboxMatrix =
gfxMatrix(bbox.Width(), 0, 0, bbox.Height(), bbox.X(), bbox.Y());
}
const nsSVGAnimatedTransformList* animTransformList =
GetGradientTransformList(mContent);
if (!animTransformList)
return bboxMatrix;
gfxMatrix gradientTransform =
animTransformList->GetAnimValue().GetConsolidationMatrix();
return bboxMatrix.PreMultiply(gradientTransform);
}
dom::SVGLinearGradientElement*
nsSVGGradientFrame::GetLinearGradientWithLength(uint32_t aIndex,
dom::SVGLinearGradientElement* aDefault)
{
// If this was a linear gradient with the required length, we would have
// already found it in nsSVGLinearGradientFrame::GetLinearGradientWithLength.
// Since we didn't find the length, continue looking down the chain.
AutoGradientReferencer gradientRef(this);
nsSVGGradientFrame *next = GetReferencedGradientIfNotInUse();
return next ? next->GetLinearGradientWithLength(aIndex, aDefault) : aDefault;
}
dom::SVGRadialGradientElement*
nsSVGGradientFrame::GetRadialGradientWithLength(uint32_t aIndex,
dom::SVGRadialGradientElement* aDefault)
{
// If this was a radial gradient with the required length, we would have
// already found it in nsSVGRadialGradientFrame::GetRadialGradientWithLength.
// Since we didn't find the length, continue looking down the chain.
AutoGradientReferencer gradientRef(this);
nsSVGGradientFrame *next = GetReferencedGradientIfNotInUse();
return next ? next->GetRadialGradientWithLength(aIndex, aDefault) : aDefault;
}
//----------------------------------------------------------------------
// nsSVGPaintServerFrame methods:
//helper
static void GetStopInformation(nsIFrame* aStopFrame,
float *aOffset,
nscolor *aStopColor,
float *aStopOpacity)
{
nsIContent* stopContent = aStopFrame->GetContent();
MOZ_ASSERT(stopContent && stopContent->IsSVGElement(nsGkAtoms::stop));
static_cast<SVGStopElement*>(stopContent)->
GetAnimatedNumberValues(aOffset, nullptr);
*aOffset = mozilla::clamped(*aOffset, 0.0f, 1.0f);
*aStopColor = aStopFrame->StyleSVGReset()->mStopColor;
*aStopOpacity = aStopFrame->StyleSVGReset()->mStopOpacity;
}
already_AddRefed<gfxPattern>
nsSVGGradientFrame::GetPaintServerPattern(nsIFrame* aSource,
const DrawTarget* aDrawTarget,
const gfxMatrix& aContextMatrix,
nsStyleSVGPaint nsStyleSVG::*aFillOrStroke,
float aGraphicOpacity,
const gfxRect* aOverrideBounds)
{
uint16_t gradientUnits = GetGradientUnits();
MOZ_ASSERT(gradientUnits == SVG_UNIT_TYPE_OBJECTBOUNDINGBOX ||
gradientUnits == SVG_UNIT_TYPE_USERSPACEONUSE);
if (gradientUnits == SVG_UNIT_TYPE_USERSPACEONUSE) {
// Set mSource for this consumer.
// If this gradient is applied to text, our caller will be the glyph, which
// is not an element, so we need to get the parent
mSource = aSource->GetContent()->IsNodeOfType(nsINode::eTEXT) ?
aSource->GetParent() : aSource;
}
AutoTArray<nsIFrame*,8> stopFrames;
GetStopFrames(&stopFrames);
uint32_t nStops = stopFrames.Length();
// SVG specification says that no stops should be treated like
// the corresponding fill or stroke had "none" specified.
if (nStops == 0) {
RefPtr<gfxPattern> pattern = new gfxPattern(Color());
return pattern.forget();
}
if (nStops == 1 || GradientVectorLengthIsZero()) {
// The gradient paints a single colour, using the stop-color of the last
// gradient step if there are more than one.
float stopOpacity = stopFrames[nStops-1]->StyleSVGReset()->mStopOpacity;
nscolor stopColor = stopFrames[nStops-1]->StyleSVGReset()->mStopColor;
Color stopColor2 = Color::FromABGR(stopColor);
stopColor2.a *= stopOpacity * aGraphicOpacity;
RefPtr<gfxPattern> pattern = new gfxPattern(stopColor2);
return pattern.forget();
}
// Get the transform list (if there is one). We do this after the returns
// above since this call can be expensive when "gradientUnits" is set to
// "objectBoundingBox" (since that requiring a GetBBox() call).
gfxMatrix patternMatrix = GetGradientTransform(aSource, aOverrideBounds);
if (patternMatrix.IsSingular()) {
return nullptr;
}
// revert any vector effect transform so that the gradient appears unchanged
if (aFillOrStroke == &nsStyleSVG::mStroke) {
gfxMatrix userToOuterSVG;
if (nsSVGUtils::GetNonScalingStrokeTransform(aSource, &userToOuterSVG)) {
patternMatrix *= userToOuterSVG;
}
}
if (!patternMatrix.Invert()) {
return nullptr;
}
RefPtr<gfxPattern> gradient = CreateGradient();
if (!gradient || gradient->CairoStatus())
return nullptr;
uint16_t aSpread = GetSpreadMethod();
if (aSpread == SVG_SPREADMETHOD_PAD)
gradient->SetExtend(ExtendMode::CLAMP);
else if (aSpread == SVG_SPREADMETHOD_REFLECT)
gradient->SetExtend(ExtendMode::REFLECT);
else if (aSpread == SVG_SPREADMETHOD_REPEAT)
gradient->SetExtend(ExtendMode::REPEAT);
gradient->SetMatrix(patternMatrix);
// setup stops
float lastOffset = 0.0f;
for (uint32_t i = 0; i < nStops; i++) {
float offset, stopOpacity;
nscolor stopColor;
GetStopInformation(stopFrames[i], &offset, &stopColor, &stopOpacity);
if (offset < lastOffset)
offset = lastOffset;
else
lastOffset = offset;
Color stopColor2 = Color::FromABGR(stopColor);
stopColor2.a *= stopOpacity * aGraphicOpacity;
gradient->AddColorStop(offset, stopColor2);
}
return gradient.forget();
}
// Private (helper) methods
nsSVGGradientFrame *
nsSVGGradientFrame::GetReferencedGradient()
{
if (mNoHRefURI)
return nullptr;
nsSVGPaintingProperty *property =
Properties().Get(nsSVGEffects::HrefAsPaintingProperty());
if (!property) {
// Fetch our gradient element's href or xlink:href attribute
dom::SVGGradientElement* grad =
static_cast<dom::SVGGradientElement*>(mContent);
nsAutoString href;
if (grad->mStringAttributes[dom::SVGGradientElement::HREF]
.IsExplicitlySet()) {
grad->mStringAttributes[dom::SVGGradientElement::HREF]
.GetAnimValue(href, grad);
} else {
grad->mStringAttributes[dom::SVGGradientElement::XLINK_HREF]
.GetAnimValue(href, grad);
}
if (href.IsEmpty()) {
mNoHRefURI = true;
return nullptr; // no URL
}
// Convert href to an nsIURI
nsCOMPtr<nsIURI> targetURI;
nsCOMPtr<nsIURI> base = mContent->GetBaseURI();
nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(targetURI), href,
mContent->GetUncomposedDoc(), base);
property =
nsSVGEffects::GetPaintingProperty(targetURI, this,
nsSVGEffects::HrefAsPaintingProperty());
if (!property)
return nullptr;
}
nsIFrame *result = property->GetReferencedFrame();
if (!result)
return nullptr;
nsIAtom* frameType = result->GetType();
if (frameType != nsGkAtoms::svgLinearGradientFrame &&
frameType != nsGkAtoms::svgRadialGradientFrame)
return nullptr;
return static_cast<nsSVGGradientFrame*>(result);
}
nsSVGGradientFrame *
nsSVGGradientFrame::GetReferencedGradientIfNotInUse()
{
nsSVGGradientFrame *referenced = GetReferencedGradient();
if (!referenced)
return nullptr;
if (referenced->mLoopFlag) {
// XXXjwatt: we should really send an error to the JavaScript Console here:
NS_WARNING("gradient reference loop detected while inheriting attribute!");
return nullptr;
}
return referenced;
}
void
nsSVGGradientFrame::GetStopFrames(nsTArray<nsIFrame*>* aStopFrames)
{
nsIFrame *stopFrame = nullptr;
for (stopFrame = mFrames.FirstChild(); stopFrame;
stopFrame = stopFrame->GetNextSibling()) {
if (stopFrame->GetType() == nsGkAtoms::svgStopFrame) {
aStopFrames->AppendElement(stopFrame);
}
}
if (aStopFrames->Length() > 0) {
return;
}
// Our gradient element doesn't have stops - try to "inherit" them
AutoGradientReferencer gradientRef(this);
nsSVGGradientFrame* next = GetReferencedGradientIfNotInUse();
if (!next) {
return;
}
return next->GetStopFrames(aStopFrames);
}
// -------------------------------------------------------------------------
// Linear Gradients
// -------------------------------------------------------------------------
#ifdef DEBUG
void
nsSVGLinearGradientFrame::Init(nsIContent* aContent,
nsContainerFrame* aParent,
nsIFrame* aPrevInFlow)
{
NS_ASSERTION(aContent->IsSVGElement(nsGkAtoms::linearGradient),
"Content is not an SVG linearGradient");
nsSVGGradientFrame::Init(aContent, aParent, aPrevInFlow);
}
#endif /* DEBUG */
nsIAtom*
nsSVGLinearGradientFrame::GetType() const
{
return nsGkAtoms::svgLinearGradientFrame;
}
nsresult
nsSVGLinearGradientFrame::AttributeChanged(int32_t aNameSpaceID,
nsIAtom* aAttribute,
int32_t aModType)
{
if (aNameSpaceID == kNameSpaceID_None &&
(aAttribute == nsGkAtoms::x1 ||
aAttribute == nsGkAtoms::y1 ||
aAttribute == nsGkAtoms::x2 ||
aAttribute == nsGkAtoms::y2)) {
nsSVGEffects::InvalidateDirectRenderingObservers(this);
}
return nsSVGGradientFrame::AttributeChanged(aNameSpaceID,
aAttribute, aModType);
}
//----------------------------------------------------------------------
float
nsSVGLinearGradientFrame::GetLengthValue(uint32_t aIndex)
{
dom::SVGLinearGradientElement* lengthElement =
GetLinearGradientWithLength(aIndex,
static_cast<dom::SVGLinearGradientElement*>(mContent));
// We passed in mContent as a fallback, so, assuming mContent is non-null, the
// return value should also be non-null.
MOZ_ASSERT(lengthElement,
"Got unexpected null element from GetLinearGradientWithLength");
const nsSVGLength2 &length = lengthElement->mLengthAttributes[aIndex];
// Object bounding box units are handled by setting the appropriate
// transform in GetGradientTransform, but we need to handle user
// space units as part of the individual Get* routines. Fixes 323669.
uint16_t gradientUnits = GetGradientUnits();
if (gradientUnits == SVG_UNIT_TYPE_USERSPACEONUSE) {
return nsSVGUtils::UserSpace(mSource, &length);
}
NS_ASSERTION(
gradientUnits == SVG_UNIT_TYPE_OBJECTBOUNDINGBOX,
"Unknown gradientUnits type");
return length.GetAnimValue(static_cast<SVGSVGElement*>(nullptr));
}
dom::SVGLinearGradientElement*
nsSVGLinearGradientFrame::GetLinearGradientWithLength(uint32_t aIndex,
dom::SVGLinearGradientElement* aDefault)
{
dom::SVGLinearGradientElement* thisElement =
static_cast<dom::SVGLinearGradientElement*>(mContent);
const nsSVGLength2 &length = thisElement->mLengthAttributes[aIndex];
if (length.IsExplicitlySet()) {
return thisElement;
}
return nsSVGGradientFrame::GetLinearGradientWithLength(aIndex, aDefault);
}
bool
nsSVGLinearGradientFrame::GradientVectorLengthIsZero()
{
return GetLengthValue(dom::SVGLinearGradientElement::ATTR_X1) ==
GetLengthValue(dom::SVGLinearGradientElement::ATTR_X2) &&
GetLengthValue(dom::SVGLinearGradientElement::ATTR_Y1) ==
GetLengthValue(dom::SVGLinearGradientElement::ATTR_Y2);
}
already_AddRefed<gfxPattern>
nsSVGLinearGradientFrame::CreateGradient()
{
float x1, y1, x2, y2;
x1 = GetLengthValue(dom::SVGLinearGradientElement::ATTR_X1);
y1 = GetLengthValue(dom::SVGLinearGradientElement::ATTR_Y1);
x2 = GetLengthValue(dom::SVGLinearGradientElement::ATTR_X2);
y2 = GetLengthValue(dom::SVGLinearGradientElement::ATTR_Y2);
RefPtr<gfxPattern> pattern = new gfxPattern(x1, y1, x2, y2);
return pattern.forget();
}
// -------------------------------------------------------------------------
// Radial Gradients
// -------------------------------------------------------------------------
#ifdef DEBUG
void
nsSVGRadialGradientFrame::Init(nsIContent* aContent,
nsContainerFrame* aParent,
nsIFrame* aPrevInFlow)
{
NS_ASSERTION(aContent->IsSVGElement(nsGkAtoms::radialGradient),
"Content is not an SVG radialGradient");
nsSVGGradientFrame::Init(aContent, aParent, aPrevInFlow);
}
#endif /* DEBUG */
nsIAtom*
nsSVGRadialGradientFrame::GetType() const
{
return nsGkAtoms::svgRadialGradientFrame;
}
nsresult
nsSVGRadialGradientFrame::AttributeChanged(int32_t aNameSpaceID,
nsIAtom* aAttribute,
int32_t aModType)
{
if (aNameSpaceID == kNameSpaceID_None &&
(aAttribute == nsGkAtoms::r ||
aAttribute == nsGkAtoms::cx ||
aAttribute == nsGkAtoms::cy ||
aAttribute == nsGkAtoms::fx ||
aAttribute == nsGkAtoms::fy)) {
nsSVGEffects::InvalidateDirectRenderingObservers(this);
}
return nsSVGGradientFrame::AttributeChanged(aNameSpaceID,
aAttribute, aModType);
}
//----------------------------------------------------------------------
float
nsSVGRadialGradientFrame::GetLengthValue(uint32_t aIndex)
{
dom::SVGRadialGradientElement* lengthElement =
GetRadialGradientWithLength(aIndex,
static_cast<dom::SVGRadialGradientElement*>(mContent));
// We passed in mContent as a fallback, so, assuming mContent is non-null,
// the return value should also be non-null.
MOZ_ASSERT(lengthElement,
"Got unexpected null element from GetRadialGradientWithLength");
return GetLengthValueFromElement(aIndex, *lengthElement);
}
float
nsSVGRadialGradientFrame::GetLengthValue(uint32_t aIndex, float aDefaultValue)
{
dom::SVGRadialGradientElement* lengthElement =
GetRadialGradientWithLength(aIndex, nullptr);
return lengthElement ? GetLengthValueFromElement(aIndex, *lengthElement)
: aDefaultValue;
}
float
nsSVGRadialGradientFrame::GetLengthValueFromElement(uint32_t aIndex,
dom::SVGRadialGradientElement& aElement)
{
const nsSVGLength2 &length = aElement.mLengthAttributes[aIndex];
// Object bounding box units are handled by setting the appropriate
// transform in GetGradientTransform, but we need to handle user
// space units as part of the individual Get* routines. Fixes 323669.
uint16_t gradientUnits = GetGradientUnits();
if (gradientUnits == SVG_UNIT_TYPE_USERSPACEONUSE) {
return nsSVGUtils::UserSpace(mSource, &length);
}
NS_ASSERTION(
gradientUnits == SVG_UNIT_TYPE_OBJECTBOUNDINGBOX,
"Unknown gradientUnits type");
return length.GetAnimValue(static_cast<SVGSVGElement*>(nullptr));
}
dom::SVGRadialGradientElement*
nsSVGRadialGradientFrame::GetRadialGradientWithLength(uint32_t aIndex,
dom::SVGRadialGradientElement* aDefault)
{
dom::SVGRadialGradientElement* thisElement =
static_cast<dom::SVGRadialGradientElement*>(mContent);
const nsSVGLength2 &length = thisElement->mLengthAttributes[aIndex];
if (length.IsExplicitlySet()) {
return thisElement;
}
return nsSVGGradientFrame::GetRadialGradientWithLength(aIndex, aDefault);
}
bool
nsSVGRadialGradientFrame::GradientVectorLengthIsZero()
{
return GetLengthValue(dom::SVGRadialGradientElement::ATTR_R) == 0;
}
already_AddRefed<gfxPattern>
nsSVGRadialGradientFrame::CreateGradient()
{
float cx, cy, r, fx, fy;
cx = GetLengthValue(dom::SVGRadialGradientElement::ATTR_CX);
cy = GetLengthValue(dom::SVGRadialGradientElement::ATTR_CY);
r = GetLengthValue(dom::SVGRadialGradientElement::ATTR_R);
// If fx or fy are not set, use cx/cy instead
fx = GetLengthValue(dom::SVGRadialGradientElement::ATTR_FX, cx);
fy = GetLengthValue(dom::SVGRadialGradientElement::ATTR_FY, cy);
if (fx != cx || fy != cy) {
// The focal point (fFx and fFy) must be clamped to be *inside* - not on -
// the circumference of the gradient or we'll get rendering anomalies. We
// calculate the distance from the focal point to the gradient center and
// make sure it is *less* than the gradient radius.
// 1/128 is the limit of the fractional part of cairo's 24.8 fixed point
// representation divided by 2 to ensure that we get different cairo
// fractions
double dMax = std::max(0.0, r - 1.0/128);
float dx = fx - cx;
float dy = fy - cy;
double d = sqrt((dx * dx) + (dy * dy));
if (d > dMax) {
double angle = atan2(dy, dx);
fx = (float)(dMax * cos(angle)) + cx;
fy = (float)(dMax * sin(angle)) + cy;
}
}
RefPtr<gfxPattern> pattern = new gfxPattern(fx, fy, 0, cx, cy, r);
return pattern.forget();
}
// -------------------------------------------------------------------------
// Public functions
// -------------------------------------------------------------------------
nsIFrame*
NS_NewSVGLinearGradientFrame(nsIPresShell* aPresShell,
nsStyleContext* aContext)
{
return new (aPresShell) nsSVGLinearGradientFrame(aContext);
}
NS_IMPL_FRAMEARENA_HELPERS(nsSVGLinearGradientFrame)
nsIFrame*
NS_NewSVGRadialGradientFrame(nsIPresShell* aPresShell,
nsStyleContext* aContext)
{
return new (aPresShell) nsSVGRadialGradientFrame(aContext);
}
NS_IMPL_FRAMEARENA_HELPERS(nsSVGRadialGradientFrame)