gecko/layout/svg/nsSVGTextFrame.cpp

486 lines
14 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 "nsSVGTextFrame.h"
// Keep others in (case-insensitive) order:
#include "nsGkAtoms.h"
#include "mozilla/dom/SVGIRect.h"
#include "nsISVGGlyphFragmentNode.h"
#include "nsSVGEffects.h"
#include "nsSVGGlyphFrame.h"
#include "nsSVGIntegrationUtils.h"
#include "nsSVGTextPathFrame.h"
#include "nsSVGUtils.h"
#include "SVGGraphicsElement.h"
#include "SVGLengthList.h"
using namespace mozilla;
//----------------------------------------------------------------------
// Implementation
nsIFrame*
NS_NewSVGTextFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
{
return new (aPresShell) nsSVGTextFrame(aContext);
}
NS_IMPL_FRAMEARENA_HELPERS(nsSVGTextFrame)
//----------------------------------------------------------------------
// nsIFrame methods
#ifdef DEBUG
void
nsSVGTextFrame::Init(nsIContent* aContent,
nsIFrame* aParent,
nsIFrame* aPrevInFlow)
{
NS_ASSERTION(aContent->IsSVG(nsGkAtoms::text),
"Content is not an SVG text");
nsSVGTextFrameBase::Init(aContent, aParent, aPrevInFlow);
}
#endif /* DEBUG */
NS_IMETHODIMP
nsSVGTextFrame::AttributeChanged(int32_t aNameSpaceID,
nsIAtom* aAttribute,
int32_t aModType)
{
if (aNameSpaceID != kNameSpaceID_None)
return NS_OK;
if (aAttribute == nsGkAtoms::transform) {
// We don't invalidate for transform changes (the layers code does that).
// Also note that SVGTransformableElement::GetAttributeChangeHint will
// return nsChangeHint_UpdateOverflow for "transform" attribute changes
// and cause DoApplyRenderingChangeToTree to make the SchedulePaint call.
NotifySVGChanged(TRANSFORM_CHANGED);
} else if (aAttribute == nsGkAtoms::x ||
aAttribute == nsGkAtoms::y ||
aAttribute == nsGkAtoms::dx ||
aAttribute == nsGkAtoms::dy ||
aAttribute == nsGkAtoms::rotate) {
nsSVGEffects::InvalidateRenderingObservers(this);
nsSVGUtils::ScheduleReflowSVG(this);
NotifyGlyphMetricsChange();
}
return NS_OK;
}
nsIAtom *
nsSVGTextFrame::GetType() const
{
return nsGkAtoms::svgTextFrame;
}
void
nsSVGTextFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists)
{
UpdateGlyphPositioning(true);
nsSVGTextFrameBase::BuildDisplayList(aBuilder, aDirtyRect, aLists);
}
//----------------------------------------------------------------------
// nsSVGTextContainerFrame
uint32_t
nsSVGTextFrame::GetNumberOfChars()
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetNumberOfChars();
}
float
nsSVGTextFrame::GetComputedTextLength()
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetComputedTextLength();
}
float
nsSVGTextFrame::GetSubStringLength(uint32_t charnum, uint32_t nchars)
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetSubStringLength(charnum, nchars);
}
int32_t
nsSVGTextFrame::GetCharNumAtPosition(nsISVGPoint *point)
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetCharNumAtPosition(point);
}
NS_IMETHODIMP
nsSVGTextFrame::GetStartPositionOfChar(uint32_t charnum, nsISupports **_retval)
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetStartPositionOfChar(charnum, _retval);
}
NS_IMETHODIMP
nsSVGTextFrame::GetEndPositionOfChar(uint32_t charnum, nsISupports **_retval)
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetEndPositionOfChar(charnum, _retval);
}
NS_IMETHODIMP
nsSVGTextFrame::GetExtentOfChar(uint32_t charnum, dom::SVGIRect **_retval)
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetExtentOfChar(charnum, _retval);
}
NS_IMETHODIMP
nsSVGTextFrame::GetRotationOfChar(uint32_t charnum, float *_retval)
{
UpdateGlyphPositioning(false);
return nsSVGTextFrameBase::GetRotationOfChar(charnum, _retval);
}
//----------------------------------------------------------------------
// nsISVGChildFrame methods
void
nsSVGTextFrame::NotifySVGChanged(uint32_t aFlags)
{
NS_ABORT_IF_FALSE(aFlags & (TRANSFORM_CHANGED | COORD_CONTEXT_CHANGED),
"Invalidation logic may need adjusting");
bool updateGlyphMetrics = false;
if (aFlags & COORD_CONTEXT_CHANGED) {
updateGlyphMetrics = true;
}
if (aFlags & TRANSFORM_CHANGED) {
if (mCanvasTM && mCanvasTM->IsSingular()) {
// We won't have calculated the glyph positions correctly
updateGlyphMetrics = true;
}
// make sure our cached transform matrix gets (lazily) updated
mCanvasTM = nullptr;
}
if (updateGlyphMetrics) {
// Ancestor changes can't affect how we render from the perspective of
// any rendering observers that we may have, so we don't need to
// invalidate them. We also don't need to invalidate ourself, since our
// changed ancestor will have invalidated its entire area, which includes
// our area.
// For perf reasons we call this before calling NotifySVGChanged() below.
nsSVGUtils::ScheduleReflowSVG(this);
}
nsSVGTextFrameBase::NotifySVGChanged(aFlags);
if (updateGlyphMetrics) {
// If we are positioned using percentage values we need to update our
// position whenever our viewport's dimensions change.
// XXX We could check here whether the text frame or any of its children
// have any percentage co-ordinates and only update if they don't. This
// may not be worth it as we might need to check each glyph
NotifyGlyphMetricsChange();
}
}
NS_IMETHODIMP
nsSVGTextFrame::PaintSVG(nsRenderingContext* aContext,
const nsIntRect *aDirtyRect)
{
NS_ASSERTION(!NS_SVGDisplayListPaintingEnabled() ||
(mState & NS_FRAME_IS_NONDISPLAY),
"If display lists are enabled, only painting of non-display "
"SVG should take this code path");
UpdateGlyphPositioning(true);
return nsSVGTextFrameBase::PaintSVG(aContext, aDirtyRect);
}
NS_IMETHODIMP_(nsIFrame*)
nsSVGTextFrame::GetFrameForPoint(const nsPoint &aPoint)
{
NS_ASSERTION(!NS_SVGDisplayListHitTestingEnabled() ||
(mState & NS_FRAME_IS_NONDISPLAY),
"If display lists are enabled, only hit-testing of non-display "
"SVG should take this code path");
UpdateGlyphPositioning(true);
return nsSVGTextFrameBase::GetFrameForPoint(aPoint);
}
void
nsSVGTextFrame::ReflowSVG()
{
NS_ASSERTION(nsSVGUtils::OuterSVGIsCallingReflowSVG(this),
"This call is probably a wasteful mistake");
NS_ABORT_IF_FALSE(!(GetStateBits() & NS_FRAME_IS_NONDISPLAY),
"ReflowSVG mechanism not designed for this");
if (!nsSVGUtils::NeedsReflowSVG(this)) {
NS_ASSERTION(!(mState & NS_STATE_SVG_POSITIONING_DIRTY), "How did this happen?");
return;
}
// UpdateGlyphPositioning may have been called under DOM calls and cleared
// NS_STATE_SVG_POSITIONING_DIRTY. We may now have better positioning, though, so
// set it to true so that UpdateGlyphPositioning will do its work.
AddStateBits(NS_STATE_SVG_POSITIONING_DIRTY);
UpdateGlyphPositioning(false);
// We leave it up to nsSVGTextFrameBase::ReflowSVG to invalidate. XXXSDL
// With glyph positions updated, our descendants can invalidate their new
// areas correctly:
nsSVGTextFrameBase::ReflowSVG();
}
SVGBBox
nsSVGTextFrame::GetBBoxContribution(const gfxMatrix &aToBBoxUserspace,
uint32_t aFlags)
{
UpdateGlyphPositioning(true);
return nsSVGTextFrameBase::GetBBoxContribution(aToBBoxUserspace, aFlags);
}
//----------------------------------------------------------------------
// nsSVGContainerFrame methods:
gfxMatrix
nsSVGTextFrame::GetCanvasTM(uint32_t aFor)
{
if (!(GetStateBits() & NS_FRAME_IS_NONDISPLAY)) {
if ((aFor == FOR_PAINTING && NS_SVGDisplayListPaintingEnabled()) ||
(aFor == FOR_HIT_TESTING && NS_SVGDisplayListHitTestingEnabled())) {
return nsSVGIntegrationUtils::GetCSSPxToDevPxMatrix(this);
}
}
if (!mCanvasTM) {
NS_ASSERTION(mParent, "null parent");
nsSVGContainerFrame *parent = static_cast<nsSVGContainerFrame*>(mParent);
dom::SVGGraphicsElement *content = static_cast<dom::SVGGraphicsElement*>(mContent);
gfxMatrix tm =
content->PrependLocalTransformsTo(parent->GetCanvasTM(aFor));
mCanvasTM = new gfxMatrix(tm);
}
return *mCanvasTM;
}
//----------------------------------------------------------------------
//
static void
MarkDirtyBitsOnDescendants(nsIFrame *aFrame)
{
// Do not skip marking of aFrame or any of its descendants if they have
// the NS_FRAME_IS_DIRTY set, because some of their descendants may not
// have it set, and we need all descendants to be dirty.
if (aFrame->GetStateBits() & (NS_FRAME_FIRST_REFLOW)) {
// Nothing to do if our outer-<svg> hasn't yet had its initial reflow.
return;
}
nsIFrame* kid = aFrame->GetFirstPrincipalChild();
while (kid) {
nsISVGChildFrame* svgkid = do_QueryFrame(kid);
if (svgkid) {
MarkDirtyBitsOnDescendants(kid);
kid->AddStateBits(NS_FRAME_IS_DIRTY);
}
kid = kid->GetNextSibling();
}
}
void
nsSVGTextFrame::NotifyGlyphMetricsChange()
{
// NotifySVGChanged isn't appropriate here, so we just mark our descendants
// as fully dirty to get ReflowSVG() called on them:
MarkDirtyBitsOnDescendants(this);
nsSVGEffects::InvalidateRenderingObservers(this);
nsSVGUtils::ScheduleReflowSVG(this);
AddStateBits(NS_STATE_SVG_POSITIONING_DIRTY);
}
void
nsSVGTextFrame::SetWhitespaceHandling(nsSVGGlyphFrame *aFrame)
{
SetWhitespaceCompression();
nsSVGGlyphFrame* firstFrame = aFrame;
bool trimLeadingWhitespace = true;
nsSVGGlyphFrame* lastNonWhitespaceFrame = aFrame;
// If the previous frame ended with whitespace
// then display of leading whitespace should be suppressed
// when we are compressing whitespace.
while (aFrame) {
if (!aFrame->IsAllWhitespace()) {
lastNonWhitespaceFrame = aFrame;
}
aFrame->SetTrimLeadingWhitespace(trimLeadingWhitespace);
trimLeadingWhitespace = aFrame->EndsWithWhitespace();
aFrame = aFrame->GetNextGlyphFrame();
}
// When there is only whitespace left we need to trim off
// the end of the last frame that isn't entirely whitespace.
// Making sure that we reset earlier frames as they may once
// have been the last non-whitespace frame.
aFrame = firstFrame;
while (aFrame != lastNonWhitespaceFrame) {
aFrame->SetTrimTrailingWhitespace(false);
aFrame = aFrame->GetNextGlyphFrame();
}
// We're at the last non-whitespace frame so trim off the end
// and make sure we set one of the trim bits so that any
// further whitespace is compressed to nothing
while (aFrame) {
aFrame->SetTrimTrailingWhitespace(true);
aFrame = aFrame->GetNextGlyphFrame();
}
}
void
nsSVGTextFrame::UpdateGlyphPositioning(bool aForceGlobalTransform)
{
if (!(mState & NS_STATE_SVG_POSITIONING_DIRTY))
return;
RemoveStateBits(NS_STATE_SVG_POSITIONING_DIRTY);
nsISVGGlyphFragmentNode* node = GetFirstGlyphFragmentChildNode();
if (!node)
return;
nsSVGGlyphFrame *frame, *firstFrame;
firstFrame = node->GetFirstGlyphFrame();
if (!firstFrame) {
return;
}
SetWhitespaceHandling(firstFrame);
BuildPositionList(0, 0);
gfxPoint ctp(0.0, 0.0);
// loop over chunks
while (firstFrame) {
nsSVGTextPathFrame *textPath = firstFrame->FindTextPathParent();
nsTArray<float> effectiveXList, effectiveYList;
firstFrame->GetEffectiveXY(firstFrame->GetNumberOfChars(),
effectiveXList, effectiveYList);
if (!effectiveXList.IsEmpty()) ctp.x = effectiveXList[0];
if (!textPath && !effectiveYList.IsEmpty()) ctp.y = effectiveYList[0];
// check for startOffset on textPath
if (textPath) {
if (!textPath->GetPathFrame()) {
// invalid text path, give up
return;
}
ctp.x = textPath->GetStartOffset();
}
// determine x offset based on text_anchor:
uint8_t anchor = firstFrame->GetTextAnchor();
/**
* XXXsmontagu: The SVG spec is very vague as to how 'text-anchor'
* interacts with bidirectional text. It says:
*
* "For scripts that are inherently right to left such as Hebrew and
* Arabic [text-anchor: start] is equivalent to right alignment."
* and
* "For scripts that are inherently right to left such as Hebrew and
* Arabic, [text-anchor: end] is equivalent to left alignment.
*
* It's not clear how this should be implemented in terms of defined
* properties, i.e. how one should determine that a particular element
* contains a script that is inherently right to left.
*
* The code below follows http://www.w3.org/TR/SVGTiny12/text.html#TextAnchorProperty
* and swaps the values of text-anchor: end and text-anchor: start
* whenever the 'direction' property is rtl.
*
* This is probably the "right" thing to do, but other browsers don't do it,
* so I am leaving it inside #if 0 for now for interoperability.
*
* See also XXXsmontagu comments in nsSVGGlyphFrame::EnsureTextRun
*/
#if 0
if (StyleVisibility()->mDirection == NS_STYLE_DIRECTION_RTL) {
if (anchor == NS_STYLE_TEXT_ANCHOR_END) {
anchor = NS_STYLE_TEXT_ANCHOR_START;
} else if (anchor == NS_STYLE_TEXT_ANCHOR_START) {
anchor = NS_STYLE_TEXT_ANCHOR_END;
}
}
#endif
float chunkLength = 0.0f;
if (anchor != NS_STYLE_TEXT_ANCHOR_START) {
// need to get the total chunk length
frame = firstFrame;
while (frame) {
chunkLength += frame->GetAdvance(aForceGlobalTransform);
frame = frame->GetNextGlyphFrame();
if (frame && frame->IsAbsolutelyPositioned())
break;
}
}
if (anchor == NS_STYLE_TEXT_ANCHOR_MIDDLE)
ctp.x -= chunkLength/2.0f;
else if (anchor == NS_STYLE_TEXT_ANCHOR_END)
ctp.x -= chunkLength;
// set position of each frame in this chunk:
frame = firstFrame;
while (frame) {
frame->SetGlyphPosition(&ctp, aForceGlobalTransform);
frame = frame->GetNextGlyphFrame();
if (frame && frame->IsAbsolutelyPositioned())
break;
}
firstFrame = frame;
}
}