Mozilla/mozilla/layout/mathml/base/src/nsMathMLContainerFrame.cpp
rbs%maths.uq.edu.au fa9816443f [MATHML]. Laying some groundwork to pave the way for the future landing of Shyjan Mahamud's TeX alignment code.
git-svn-id: svn://10.0.0.236/trunk@57109 18797224-902f-48f8-a5cc-f745e15eee43
2000-01-07 14:49:46 +00:00

1152 lines
44 KiB
C++

/*
* The contents of this file are subject to the Mozilla Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is Mozilla MathML Project.
*
* The Initial Developer of the Original Code is The University Of
* Queensland. Portions created by The University Of Queensland are
* Copyright (C) 1999 The University Of Queensland. All Rights Reserved.
*
* Contributor(s):
* Roger B. Sidje <rbs@maths.uq.edu.au>
* David J. Fiddes <D.J.Fiddes@hw.ac.uk>
*/
#include "nsCOMPtr.h"
#include "nsHTMLParts.h"
#include "nsIHTMLContent.h"
#include "nsFrame.h"
#include "nsLineLayout.h"
#include "nsHTMLIIDs.h"
#include "nsIPresContext.h"
#include "nsIPresShell.h"
#include "nsHTMLAtoms.h"
#include "nsUnitConversion.h"
#include "nsIStyleContext.h"
#include "nsStyleConsts.h"
#include "nsINameSpaceManager.h"
#include "nsIRenderingContext.h"
#include "nsIFontMetrics.h"
#include "nsStyleUtil.h"
#include "nsITextContent.h"
#include "nsMathMLAtoms.h"
#include "nsMathMLParts.h"
#include "nsMathMLChar.h"
#include "nsMathMLContainerFrame.h"
//
// nsMathMLContainerFrame implementation
//
// TODO: Proper management of ignorable whitespace
// and handling of non-math related frames.
// * Should math markups only enclose other math markups?
// Why bother... we can leave them in, as hinted in the newsgroup.
//
// * Space doesn't count. Handling space is more complicated than it seems.
// We have to clean inside and outside:
// <mi> a </mi> <mo> + </mo> <mi> b </mi>
// ^ ^ ^ ^ ^ ^ ^ ^
// *Outside* currently handled using IsOnlyWhitespace().
// For whitespace only frames, their rect is set zero.
//
// *Inside* not currently handled... so the user must do <mi>a</mi>
// What to do?!
// - Add a nsTextFrame::CompressWhitespace() *if* it is MathML content?!
// - via CSS property? Support for "none/compress"? (white-space: normal | pre | nowrap)
// nsISupports
// =============================================================================
NS_IMETHODIMP
nsMathMLContainerFrame::QueryInterface(REFNSIID aIID, void** aInstancePtr)
{
if (NULL == aInstancePtr) {
return NS_ERROR_NULL_POINTER;
}
*aInstancePtr = nsnull;
if (aIID.Equals(kIMathMLFrameIID)) {
*aInstancePtr = (void*)(nsIMathMLFrame*)this;
NS_ADDREF_THIS(); // not effectual, frames are not Refcounted
return NS_OK;
}
return nsHTMLContainerFrame::QueryInterface(aIID, aInstancePtr);
}
NS_IMETHODIMP_(nsrefcnt)
nsMathMLContainerFrame::AddRef(void)
{
return NS_OK;
}
NS_IMETHODIMP_(nsrefcnt)
nsMathMLContainerFrame::Release(void)
{
return NS_OK;
}
/* ///////////////
* MathML specific - Whitespace management ...
* WHITESPACE: don't forget that whitespace doesn't count in MathML!
* empty frames shouldn't be created in MathML, oh well that's another story.
* =============================================================================
*/
PRBool
nsMathMLContainerFrame::IsOnlyWhitespace(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null arg");
PRBool rv = PR_FALSE;
// by empty frame we mean a leaf frame whose text content is empty...
nsCOMPtr<nsIContent> aContent;
aFrame->GetContent(getter_AddRefs(aContent));
if (!aContent) return PR_TRUE;
PRInt32 numKids;
aContent->ChildCount(numKids);
if (0 == numKids) {
nsCOMPtr<nsITextContent> tc(do_QueryInterface(aContent));
if (tc.get()) tc->IsOnlyWhitespace(&rv);
}
return rv;
}
void
nsMathMLContainerFrame::ReflowEmptyChild(nsIPresContext* aPresContext,
nsIFrame* aFrame)
{
// nsHTMLReflowMetrics emptySize(nsnull);
// nsHTMLReflowState emptyReflowState(aPresContext, aReflowState, aFrame, nsSize(0,0));
// nsresult rv = ReflowChild(aFrame, aPresContext, emptySize, emptyReflowState, aStatus);
// 0-size the frame
aFrame->SetRect(aPresContext, nsRect(0,0,0,0));
// 0-size the view, if any
nsIView* view = nsnull;
aFrame->GetView(aPresContext, &view);
if (view) {
nsCOMPtr<nsIViewManager> vm;
view->GetViewManager(*getter_AddRefs(vm));
vm->ResizeView(view, 0,0);
}
}
/* /////////////
* nsIMathMLFrame - support methods for precise positioning
* =============================================================================
*/
NS_IMETHODIMP
nsMathMLContainerFrame::GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics)
{
aBoundingMetrics = mBoundingMetrics;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics)
{
mBoundingMetrics = aBoundingMetrics;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::GetReference(nsPoint& aReference)
{
aReference = mReference;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::SetReference(const nsPoint& aReference)
{
mReference = aReference;
return NS_OK;
}
/* /////////////
* nsIMathMLFrame - support methods for stretchy elements
* =============================================================================
*/
NS_IMETHODIMP
nsMathMLContainerFrame::Stretch(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nsStretchDirection aStretchDirection,
nsStretchMetrics& aContainerSize,
nsStretchMetrics& aDesiredStretchSize)
{
nsresult rv = NS_OK;
if (NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags)) {
if (NS_MATHML_STRETCH_WAS_DONE(mEmbellishData.flags)) {
printf("WARNING *** it is wrong to fire stretch more than once on a frame...\n");
// NS_ASSERTION(PR_FALSE,"Stretch() was fired more than once on a frame!");
return NS_OK;
}
mEmbellishData.flags |= NS_MATHML_STRETCH_DONE;
// Pass the stretch to the first non-empty child ...
nsIFrame* childFrame = mEmbellishData.firstChild;
NS_ASSERTION(childFrame, "Something is wrong somewhere");
if (childFrame) {
nsIMathMLFrame* aMathMLFrame = nsnull;
rv = childFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
NS_ASSERTION(NS_SUCCEEDED(rv) && aMathMLFrame, "Something is wrong somewhere");
if (NS_SUCCEEDED(rv) && aMathMLFrame) {
nsHTMLReflowMetrics aReflowMetrics(nsnull);
nsRect rect;
childFrame->GetRect(rect);
// And the trick is that rect.x is still holding the descent, and rect.y
// is still holding the ascent ...
nsStretchMetrics childSize(rect.x, rect.y, rect.width, rect.height);
nsStretchMetrics container(aContainerSize);
if (aStretchDirection != NS_STRETCH_DIRECTION_DEFAULT && aStretchDirection != mEmbellishData.direction) {
// change the direction and confine the stretch to us
#if 0
GetDesiredStretchSize(aPresContext, aRenderingContext, container);
#endif
GetRect(rect);
container = nsStretchMetrics(rect.x, rect.y, rect.width, rect.height);
}
aMathMLFrame->Stretch(aPresContext, aRenderingContext,
mEmbellishData.direction, container, childSize);
childFrame->SetRect(aPresContext,
nsRect(childSize.descent, childSize.ascent,
childSize.width, childSize.height));
// We now have one child that may have changed, re-position all our children
Place(aPresContext, aRenderingContext, PR_TRUE, aReflowMetrics);
// Prepare the metrics to be returned
aDesiredStretchSize = nsStretchMetrics(aReflowMetrics);
aDesiredStretchSize.leftSpace = childSize.leftSpace;
aDesiredStretchSize.rightSpace = childSize.rightSpace;
// If our parent is not embellished, it means we are the outermost embellished
// container and so we put the spacing, otherwise we don't include the spacing,
// the outermost embellished container will take care of it.
if (!IsEmbellishOperator(mParent)) {
nsStyleFont font;
mStyleContext->GetStyle(eStyleStruct_Font, font);
nscoord em = NSToCoordRound(float(font.mFont.size));
// cache these values
mEmbellishData.leftSpace = nscoord( em * aDesiredStretchSize.leftSpace );
mEmbellishData.rightSpace = nscoord( em * aDesiredStretchSize.rightSpace );
aDesiredStretchSize.width += nscoord( (aDesiredStretchSize.leftSpace + aDesiredStretchSize.rightSpace) * em );
nscoord dx = nscoord( aDesiredStretchSize.leftSpace * em );
if (0 == dx) return NS_OK;
nsPoint origin;
childFrame = mFrames.FirstChild();
while (childFrame) {
childFrame->GetOrigin(origin);
childFrame->MoveTo(aPresContext, origin.x + dx, origin.y);
childFrame->GetNextSibling(&childFrame);
}
}
}
}
}
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::FinalizeReflow(PRInt32 aDirection,
nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nsHTMLReflowMetrics& aDesiredSize)
{
// During reflow, we use rect.x and rect.y as placeholders for the child's ascent
// and descent in expectation of a stretch command. Hence we need to ensure that
// a stretch command will actually be fired later on, after exiting from our
// reflow. If the stretch is not fired, the rect.x, and rect.y will remain
// with inappropriate data causing children to be improperly positioned.
// This helper method checks to see if our parent will fire a stretch command
// targeted at us. If not, we go ahead and fire an involutive stretch on
// ourselves. This will clear all the rect.x and rect.y, and return our
// desired size.
// First, complete the post-reflow hook.
// We use the information in our children rectangles to position them.
// If placeOrigin==false, then Place() will not touch rect.x, and rect.y.
// They will still be holding the ascent and descent for each child.
PRBool placeOrigin = !NS_MATHML_IS_EMBELLISH_OPERATOR(mEmbellishData.flags);
Place(aPresContext, aRenderingContext, placeOrigin, aDesiredSize);
if (!placeOrigin) {
// This means the rect.x and rect.y of our children were not set!!
// Don't go without checking to see if our parent will later fire a Stretch() command
// targeted at us. The Stretch() will cause the rect.x and rect.y to clear...
PRBool parentWillFireStretch = PR_FALSE;
nsEmbellishData parentData;
nsIMathMLFrame* aMathMLFrame = nsnull;
nsresult rv = mParent->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
if (NS_SUCCEEDED(rv) && aMathMLFrame) {
aMathMLFrame->GetEmbellishData(parentData);
if (NS_MATHML_WILL_STRETCH_ALL_CHILDREN(parentData.flags) ||
(NS_MATHML_WILL_STRETCH_FIRST_CHILD(parentData.flags) &&
parentData.firstChild == this)) {
parentWillFireStretch = PR_TRUE;
}
}
if (!parentWillFireStretch) {
// There is nobody who will fire the stretch for us, we do it ourselves!
// BEGIN of GETTING THE STRETCH SIZE
// What is the size that we should use to stretch our stretchy children ????
// 1) With this code, vertical stretching works. But horizontal stretching
// does not work when the firstChild happens to be the core embellished mo...
// nsRect rect;
// nsIFrame* childFrame = mEmbellishData.firstChild;
// NS_ASSERTION(childFrame, "Something is wrong somewhere");
// childFrame->GetRect(rect);
// nsStretchMetrics curSize(rect.x, rect.y, rect.width, rect.height);
// 2) With this code, horizontal stretching works. But vertical stretching
// is done in some cases where frames could have simply been kept as is.
nsStretchMetrics curSize(aDesiredSize);
// 3) With this code, we should get appropriate size when it is done !!
// GetDesiredSize(aDirection, aPresContext, aRenderingContext, curSize);
// XXX It is not clear if a direction should be imposed.
// With the default direction, the MathMLChar will attempt to stretch
// in its preferred direction.
nsStretchMetrics newSize(curSize);
Stretch(aPresContext, aRenderingContext, NS_STRETCH_DIRECTION_DEFAULT,
curSize, newSize);
aDesiredSize.width = newSize.width;
aDesiredSize.height = newSize.height;
aDesiredSize.ascent = newSize.ascent;
aDesiredSize.descent = newSize.descent;
}
}
if (nsnull != aDesiredSize.maxElementSize) {
aDesiredSize.maxElementSize->width = aDesiredSize.width;
aDesiredSize.maxElementSize->height = aDesiredSize.height;
}
// Also return our bounding metrics
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
return NS_OK;
}
// This is the method used to set the frame as an embellished container.
// It checks if the first (non-empty) child is embellished. Hence, calls
// must be bottom-up. The method must only be called from within frames who are
// entitled to be potential embellished operators as per the MathML REC.
NS_IMETHODIMP
nsMathMLContainerFrame::EmbellishOperator()
{
// Get the first non-empty child
nsIFrame* firstChild = mFrames.FirstChild();
while (firstChild) {
if (!IsOnlyWhitespace(firstChild)) break;
firstChild->GetNextSibling(&firstChild);
}
if (firstChild && IsEmbellishOperator(firstChild)) {
// Cache the first child
mEmbellishData.flags |= NS_MATHML_EMBELLISH_OPERATOR;
mEmbellishData.firstChild = firstChild;
// Cache also the inner-most embellished frame at the core of the hierarchy
nsIMathMLFrame* aMathMLFrame = nsnull;
nsresult rv = firstChild->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
NS_ASSERTION(NS_SUCCEEDED(rv) && aMathMLFrame, "Mystery!");
nsEmbellishData embellishData;
aMathMLFrame->GetEmbellishData(embellishData);
mEmbellishData.core = embellishData.core;
mEmbellishData.direction = embellishData.direction;
}
else {
mEmbellishData.flags &= ~NS_MATHML_EMBELLISH_OPERATOR;
mEmbellishData.firstChild = nsnull;
mEmbellishData.core = nsnull;
mEmbellishData.direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
}
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::GetEmbellishData(nsEmbellishData& aEmbellishData)
{
aEmbellishData = mEmbellishData;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::SetEmbellishData(const nsEmbellishData& aEmbellishData)
{
mEmbellishData = aEmbellishData;
return NS_OK;
}
PRBool
nsMathMLContainerFrame::IsEmbellishOperator(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null arg");
if (!aFrame) return PR_FALSE;
nsIMathMLFrame* aMathMLFrame = nsnull;
nsresult rv = aFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
if (NS_FAILED(rv) || !aMathMLFrame) return PR_FALSE;
nsEmbellishData aEmbellishData;
aMathMLFrame->GetEmbellishData(aEmbellishData);
return NS_MATHML_IS_EMBELLISH_OPERATOR(aEmbellishData.flags);
}
/* /////////////
* nsIMathMLFrame - support methods for scripting elements (nested frames
* within msub, msup, msubsup, munder, mover, munderover, mmultiscripts,
* mfrac, mroot, mtable).
* =============================================================================
*/
NS_IMETHODIMP
nsMathMLContainerFrame::GetPresentationData(PRInt32* aScriptLevel,
PRBool* aDisplayStyle)
{
NS_PRECONDITION(aScriptLevel && aDisplayStyle, "null arg");
*aScriptLevel = mScriptLevel;
*aDisplayStyle = mDisplayStyle;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::UpdatePresentationData(PRInt32 aScriptLevelIncrement,
PRBool aDisplayStyle)
{
mScriptLevel += aScriptLevelIncrement;
mDisplayStyle = aDisplayStyle;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::UpdatePresentationDataFromChildAt(PRInt32 aIndex,
PRInt32 aScriptLevelIncrement,
PRBool aDisplayStyle)
{
nsIFrame* childFrame = mFrames.FirstChild();
while (nsnull != childFrame) {
if (!IsOnlyWhitespace(childFrame)) {
if (0 >= aIndex--) {
nsIMathMLFrame* aMathMLFrame = nsnull;
nsresult rv = childFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
if (NS_SUCCEEDED(rv) && nsnull != aMathMLFrame) {
// update
aMathMLFrame->UpdatePresentationData(aScriptLevelIncrement, aDisplayStyle);
// propagate down the subtrees
aMathMLFrame->UpdatePresentationDataFromChildAt(0, aScriptLevelIncrement, aDisplayStyle);
}
}
}
childFrame->GetNextSibling(&childFrame);
}
return NS_OK;
}
// helper method to alter the style context
// This method is used for switching the font to a subscript/superscript font in
// mfrac, msub, msup, msubsup, munder, mover, munderover, mmultiscripts
NS_IMETHODIMP
nsMathMLContainerFrame::InsertScriptLevelStyleContext(nsIPresContext* aPresContext)
{
nsresult rv = NS_OK;
nsIFrame* nextFrame = mFrames.FirstChild();
while (nsnull != nextFrame && NS_SUCCEEDED(rv)) {
nsIFrame* childFrame = nextFrame;
rv = nextFrame->GetNextSibling(&nextFrame);
if (!IsOnlyWhitespace(childFrame) && NS_SUCCEEDED(rv)) {
// see if the child frame implements the nsIMathMLFrame interface
nsIMathMLFrame* aMathMLFrame = nsnull;
rv = childFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
if (nsnull != aMathMLFrame && NS_SUCCEEDED(rv)) {
// get the scriptlevel of the child
PRInt32 childLevel;
PRBool childDisplayStyle;
aMathMLFrame->GetPresentationData(&childLevel, &childDisplayStyle);
// Iteration to set a style context for the script level font.
// Wow, here is what is happening: the style system requires that any style context
// *must* be uniquely associated to a frame. So we insert as many frames as needed
// to scale-down (or scale-up) the fontsize.
PRInt32 gap = childLevel - mScriptLevel;
if (0 != gap) {
nsCOMPtr<nsIContent> childContent;
childFrame->GetContent(getter_AddRefs(childContent));
nsCOMPtr<nsIPresShell> shell;
aPresContext->GetShell(getter_AddRefs(shell));
nsIFrame* firstFrame = nsnull;
nsIFrame* lastFrame = this;
nsIStyleContext* lastStyleContext = mStyleContext;
nsCOMPtr<nsIStyleContext> newStyleContext;
nsAutoString fontSize = (0 < gap)
? ":-moz-math-font-size-smaller"
: ":-moz-math-font-size-larger";
nsCOMPtr<nsIAtom> fontAtom(getter_AddRefs(NS_NewAtom(fontSize)));
if (0 > gap) gap = -gap; // absolute value
while (0 < gap--) {
aPresContext->ResolvePseudoStyleContextFor(childContent, fontAtom, lastStyleContext,
PR_FALSE, getter_AddRefs(newStyleContext));
if (newStyleContext && newStyleContext.get() != lastStyleContext) {
// create a new wrapper frame and append it as sole child of the last created frame
nsIFrame* newFrame = nsnull;
NS_NewMathMLWrapperFrame(shell, &newFrame);
NS_ASSERTION(newFrame, "Failed to create new frame");
if (!newFrame) break;
newFrame->Init(aPresContext, childContent, lastFrame, newStyleContext, nsnull);
if (nsnull == firstFrame) {
firstFrame = newFrame;
}
if (this != lastFrame) {
lastFrame->SetInitialChildList(aPresContext, nsnull, newFrame);
}
lastStyleContext = newStyleContext;
lastFrame = newFrame;
}
else {
break;
}
}
if (nsnull != firstFrame) { // at least one new frame was created
mFrames.ReplaceFrame(this, childFrame, firstFrame);
childFrame->SetParent(lastFrame);
childFrame->SetNextSibling(nsnull);
aPresContext->ReParentStyleContext(childFrame, lastStyleContext);
lastFrame->SetInitialChildList(aPresContext, nsnull, childFrame);
// if the child was an embellished operator,
// make the whole list embellished as well
nsEmbellishData embellishData;
aMathMLFrame->GetEmbellishData(embellishData);
if (0 != embellishData.flags && nsnull != embellishData.firstChild) {
do { // walk the hierarchy in a bottom-up manner
rv= lastFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
NS_ASSERTION(NS_SUCCEEDED(rv) && aMathMLFrame, "Mystery!");
if (NS_FAILED(rv) || !aMathMLFrame) break;
embellishData.firstChild = childFrame;
aMathMLFrame->SetEmbellishData(embellishData);
childFrame = lastFrame;
lastFrame->GetParent(&lastFrame);
} while (lastFrame != this);
}
}
}
}
}
}
return rv;
}
/* //////////////////
* Frame construction
* =============================================================================
*/
NS_IMETHODIMP
nsMathMLContainerFrame::Init(nsIPresContext* aPresContext,
nsIContent* aContent,
nsIFrame* aParent,
nsIStyleContext* aContext,
nsIFrame* aPrevInFlow)
{
nsresult rv;
// first, let the base class do its Init()
rv = nsHTMLContainerFrame::Init(aPresContext, aContent, aParent, aContext, aPrevInFlow);
// now, if our parent implements the nsIMathMLFrame interface, we inherit
// its scriptlevel and displaystyle. If the parent later wishes to increment
// with other values, it will do so in its SetInitialChildList() method.
mScriptLevel = 0;
mDisplayStyle = PR_TRUE;
mCompressed = PR_FALSE; // for compatibility with TeX rendering
mScriptSpace = 0; // = 0.5 pt in plain TeX
mEmbellishData.flags = 0;
mEmbellishData.firstChild = nsnull;
nsIMathMLFrame* aMathMLFrame = nsnull;
nsresult res = aParent->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
if (NS_SUCCEEDED(res) && nsnull != aMathMLFrame) {
PRInt32 aScriptLevel = 0;
PRBool aDisplayStyle = PR_TRUE;
aMathMLFrame->GetPresentationData(&aScriptLevel, &aDisplayStyle);
UpdatePresentationData(aScriptLevel, aDisplayStyle);
}
return rv;
}
NS_IMETHODIMP
nsMathMLContainerFrame::SetInitialChildList(nsIPresContext* aPresContext,
nsIAtom* aListName,
nsIFrame* aChildList)
{
// First, let the base class do its job
nsresult rv;
rv = nsHTMLContainerFrame::SetInitialChildList(aPresContext, aListName, aChildList);
// Next, since we are an inline frame, and since we are a container, we have to
// be very careful with the way we treat our children. Things look okay when
// all of our children are only MathML frames. But there are problems if one of
// our children happens to be an nsInlineFrame, e.g., from generated content such
// as :before { content: open-quote } or :after { content: close-quote }
// The code asserts during reflow (in nsLineLayout::BeginSpan)
// Also there are problems when our children are hybrid, e.g., from html markups.
// In short, the nsInlineFrame class expects a number of *invariants* that are not
// met when we mix things.
// So what we do here is to wrap children that happen to be nsInlineFrames in
// anonymous block frames.
// XXX Question: Do we have to handle Insert/Remove/Append on behalf of
// these anonymous blocks?
// Note: By construction, our anonymous blocks have only one child.
nsIFrame* next = mFrames.FirstChild();
while (next) {
nsIFrame* child = next;
rv = next->GetNextSibling(&next);
if (!IsOnlyWhitespace(child)) {
nsInlineFrame* inlineFrame = nsnull;
rv = child->QueryInterface(nsInlineFrame::kInlineFrameCID, (void**)&inlineFrame);
if (NS_SUCCEEDED(rv) && inlineFrame) {
// create a new anonymous block frame to wrap this child...
nsCOMPtr<nsIPresShell> shell;
aPresContext->GetShell(getter_AddRefs(shell));
nsIFrame* anonymous;
rv = NS_NewBlockFrame(shell, &anonymous);
if (NS_FAILED(rv))
return rv;
nsCOMPtr<nsIStyleContext> newStyleContext;
aPresContext->ResolvePseudoStyleContextFor(mContent, nsHTMLAtoms::mozAnonymousBlock,
mStyleContext, PR_FALSE,
getter_AddRefs(newStyleContext));
rv = anonymous->Init(aPresContext, mContent, this, newStyleContext, nsnull);
if (NS_FAILED(rv)) {
anonymous->Destroy(aPresContext);
return rv;
}
mFrames.ReplaceFrame(this, child, anonymous);
child->SetParent(anonymous);
child->SetNextSibling(nsnull);
aPresContext->ReParentStyleContext(child, newStyleContext);
anonymous->SetInitialChildList(aPresContext, nsnull, child);
}
}
}
return rv;
}
#if 0
// helper method to compute the desired size of a frame
NS_IMETHODIMP
nsMathMLContainerFrame::GetDesiredStretchSize(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nsHTMLReflowMetrics& aDesiredSize)
{
nsresult rv = NS_OK;
nsRect rect;
nscoord count = 0;
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
if (!IsOnlyWhitespace(childFrame)) {
childFrame->GetRect(rect);
if (IsEmbellishOperator(childFrame)) {
// We have encountered an embellished operator...
// It is treated as if the embellishments were not there!
nsIMathMLFrame* aMathMLFrame = nsnull;
rv = childFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
NS_ASSERTION(NS_SUCCEEDED(rv) && aMathMLFrame, "Mystery!");
if (NS_SUCCEEDED(rv) && aMathMLFrame) {
nsEmbellishData embellishData;
aMathMLFrame->GetEmbellishData(embellishData);
embellishData.core->GetRect(rect);
}
}
if (0 == aDirection) { // for horizontal positioning of child frames like in mrow
aDesiredSize.width += rect.width;
if (aDesiredSize.ascent < rect.y) aDesiredSize.ascent = rect.y;
if (aDesiredSize.descent < rect.x) aDesiredSize.descent = rect.x;
}
else if (1 == aDirection) { // for vertical positioning of child frames like in mfrac, munder
if (0 == count) { // it is the ascent and descent of the 'base' that is returned by defaul
aDesiredSize.ascent = rect.y;
aDesiredSize.descent = rect.x;
}
if (aDesiredSize.width < rect.width) aDesiredSize.width = rect.width;
}
count++;
}
rv = childFrame->GetNextSibling(&childFrame);
NS_ASSERTION(NS_SUCCEEDED(rv),"failed to get next child");
}
aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent;
// Check if embellished operators didn't have (non-empty) siblings...
if (0 < count && 0 == aDirection && 0 == aDesiredSize.height) {
// Return the font ascent and font descent
nsCOMPtr<nsIFontMetrics> fm;
nsStyleFont font;
mStyleContext->GetStyle(eStyleStruct_Font, font);
aPresContext->GetMetricsFor(font.mFont, getter_AddRefs(fm));
fm->GetMaxAscent(aDesiredSize.ascent);
fm->GetMaxDescent(aDesiredSize.descent);
aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent;
}
if (0 < count && 1 == aDirection && 0 == aDesiredSize.width) {
// Return em
nsStyleFont font;
mStyleContext->GetStyle(eStyleStruct_Font, font);
aDesiredSize.width = NSToCoordRound(float(font.mFont.size));
}
return NS_OK;
}
#endif
// helper function to reflow token elements
// note that mBoundingMetrics is computed here
nsresult
nsMathMLContainerFrame::ReflowTokenFor(nsIFrame* aFrame,
nsIPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
NS_PRECONDITION(aFrame, "null arg");
nsresult rv = NS_OK;
// ask our children to compute their bounding metrics
nsHTMLReflowMetrics childDesiredSize(aDesiredSize.maxElementSize,
aDesiredSize.mFlags | NS_REFLOW_CALC_BOUNDING_METRICS);
nsSize availSize(aReflowState.mComputedWidth, aReflowState.mComputedHeight);
nsBoundingMetrics bm;
PRInt32 count = 0;
nsIFrame* childFrame;
aFrame->FirstChild(nsnull, &childFrame);
while (childFrame) {
if (IsOnlyWhitespace(childFrame)) {
ReflowEmptyChild(aPresContext, childFrame);
}
else {
nsHTMLReflowState childReflowState(aPresContext, aReflowState,
childFrame, availSize);
rv = NS_STATIC_CAST(nsMathMLContainerFrame*,
aFrame)->ReflowChild(childFrame,
aPresContext, childDesiredSize,
childReflowState, aStatus);
NS_ASSERTION(NS_FRAME_IS_COMPLETE(aStatus), "bad status");
if (NS_FAILED(rv)) return rv;
// origins are used as placeholders to store the child's ascent and descent.
childFrame->SetRect(aPresContext,
nsRect(childDesiredSize.descent, childDesiredSize.ascent,
childDesiredSize.width, childDesiredSize.height));
// compute and cache the bounding metrics
if (0 == count)
bm = childDesiredSize.mBoundingMetrics;
else
bm += childDesiredSize.mBoundingMetrics;
count++;
}
rv = childFrame->GetNextSibling(&childFrame);
NS_ASSERTION(NS_SUCCEEDED(rv),"failed to get next child");
}
NS_STATIC_CAST(nsMathMLContainerFrame*, aFrame)->SetBoundingMetrics(bm);
// Place and size children
NS_STATIC_CAST(nsMathMLContainerFrame*,
aFrame)->FinalizeReflow(0, aPresContext, *aReflowState.rendContext,
aDesiredSize);
return NS_OK;
}
// helper function to place token elements
// mBoundingMetrics is computed at the ReflowToken pass, it is
// not computed here because if our children may be text frames that
// do not implement the GetBoundingMetrics() interface.
nsresult
nsMathMLContainerFrame::PlaceTokenFor(nsIFrame* aFrame,
nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
PRBool aPlaceOrigin,
nsHTMLReflowMetrics& aDesiredSize)
{
aDesiredSize.width = aDesiredSize.height = aDesiredSize.ascent = aDesiredSize.descent = 0;
nsRect rect;
nsIFrame* childFrame;
aFrame->FirstChild(nsnull, &childFrame);
while (childFrame) {
if (!IsOnlyWhitespace(childFrame)) {
childFrame->GetRect(rect);
aDesiredSize.width += rect.width;
if (aDesiredSize.descent < rect.x) aDesiredSize.descent = rect.x;
if (aDesiredSize.ascent < rect.y) aDesiredSize.ascent = rect.y;
}
childFrame->GetNextSibling(&childFrame);
}
aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent;
if (aPlaceOrigin) {
nscoord dy;
nscoord dx = 0;
aFrame->FirstChild(nsnull, &childFrame);
while (childFrame) {
childFrame->GetRect(rect);
nsHTMLReflowMetrics childSize(nsnull);
childSize.width = rect.width;
childSize.height = rect.height;
// Place and size the child
dy = aDesiredSize.ascent - rect.y;
NS_STATIC_CAST(nsMathMLContainerFrame*,
aFrame)->FinishReflowChild(childFrame, aPresContext,
childSize, dx, dy, 0);
dx += rect.width;
childFrame->GetNextSibling(&childFrame);
}
}
return NS_OK;
}
// helper function to reflow all children
NS_IMETHODIMP
nsMathMLContainerFrame::ReflowChildren(PRInt32 aDirection,
nsIPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
NS_PRECONDITION(aDirection==0 || aDirection==1, "Unknown direction");
nsresult rv = NS_OK;
nsReflowStatus childStatus;
nsSize availSize(aReflowState.mComputedWidth, aReflowState.mComputedHeight);
// Asks the child to cache its bounding metrics
nsHTMLReflowMetrics childDesiredSize(aDesiredSize.maxElementSize,
aDesiredSize.mFlags | NS_REFLOW_CALC_BOUNDING_METRICS);
aDesiredSize.width = aDesiredSize.height = aDesiredSize.ascent = aDesiredSize.descent = 0;
nscoord count = 0;
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
//////////////
// WHITESPACE: don't forget that whitespace doesn't count in MathML!
if (IsOnlyWhitespace(childFrame)) {
ReflowEmptyChild(aPresContext, childFrame);
}
else {
nsHTMLReflowState childReflowState(aPresContext, aReflowState,
childFrame, availSize);
rv = ReflowChild(childFrame, aPresContext, childDesiredSize,
childReflowState, childStatus);
NS_ASSERTION(NS_FRAME_IS_COMPLETE(childStatus), "bad status");
if (NS_FAILED(rv)) return rv;
// At this stage, the origin points of the children have no use, so we will use the
// origins as placeholders to store the child's ascent and descent. Later on,
// we should set the origins so as to overwrite what we are storing there now.
childFrame->SetRect(aPresContext,
nsRect(childDesiredSize.descent, childDesiredSize.ascent,
childDesiredSize.width, childDesiredSize.height));
if (NS_MATHML_WILL_STRETCH_ALL_CHILDREN(mEmbellishData.flags) &&
IsEmbellishOperator(childFrame)) {
// We have encountered an embellished operator...
// It is treated as if the embellishments were not there!
nsIMathMLFrame* aMathMLFrame = nsnull;
rv = childFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
NS_ASSERTION(NS_SUCCEEDED(rv) && aMathMLFrame, "Mystery!");
if (NS_SUCCEEDED(rv) && aMathMLFrame) {
nsEmbellishData embellishData;
aMathMLFrame->GetEmbellishData(embellishData);
nsRect rect;
embellishData.core->GetRect(rect);
childDesiredSize.descent = rect.x;
childDesiredSize.ascent = rect.y;
childDesiredSize.width = rect.width;
childDesiredSize.height = rect.height;
#if 0
nsIRenderingContext& renderingContext = *aReflowState.rendContext;
nsStretchMetrics stretchSize;
aMathMLFrame->GetDesiredStretchSize(aPresContext, renderingContext, stretchSize);
childDesiredSize.descent = stretchSize.descent;
childDesiredSize.ascent = stretchSize.ascent;
childDesiredSize.width = stretchSize.width;
childDesiredSize.height = stretchSize.height;
#endif
}
}
if (0 == aDirection) { // for horizontal positioning of child frames like in mrow
aDesiredSize.width += childDesiredSize.width;
if (aDesiredSize.ascent < childDesiredSize.ascent) aDesiredSize.ascent = childDesiredSize.ascent;
if (aDesiredSize.descent < childDesiredSize.descent) aDesiredSize.descent = childDesiredSize.descent;
}
else if (1 == aDirection) { // for vertical positioning of child frames like in mfrac, munder
if (0 == count) { // it is the ascent and descent of the 'base' that is returned by defaul
aDesiredSize.ascent = childDesiredSize.ascent;
aDesiredSize.descent = childDesiredSize.descent;
}
if (aDesiredSize.width < childDesiredSize.width) aDesiredSize.width = childDesiredSize.width;
}
count++;
}
rv = childFrame->GetNextSibling(&childFrame);
NS_ASSERTION(NS_SUCCEEDED(rv),"failed to get next child");
}
aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent;
// Check if embellished operators didn't have (non-empty) siblings...
if (0 < count && 0 == aDirection && 0 == aDesiredSize.height) {
// Return the font ascent and font descent
nsCOMPtr<nsIFontMetrics> fm;
nsStyleFont font;
mStyleContext->GetStyle(eStyleStruct_Font, font);
aPresContext->GetMetricsFor(font.mFont, getter_AddRefs(fm));
fm->GetMaxAscent(aDesiredSize.ascent);
fm->GetMaxDescent(aDesiredSize.descent);
aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent;
}
if (0 < count && 1 == aDirection && 0 == aDesiredSize.width) {
// Return em
nsStyleFont font;
mStyleContext->GetStyle(eStyleStruct_Font, font);
aDesiredSize.width = NSToCoordRound(float(font.mFont.size));
}
return NS_OK;
}
// helper function to stretch all children
NS_IMETHODIMP
nsMathMLContainerFrame::StretchChildren(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
nsStretchDirection aStretchDirection,
nsStretchMetrics& aContainerSize)
{
nsRect rect;
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
if (mEmbellishData.firstChild == childFrame) {
// Skip this child... because:
// If we are here it means we are an embellished container and
// for now, we don't touch our embellished child frame.
// Its stretch will be handled separatedly when we receive
// stretch command fired by our parent frame.
}
else {
nsIMathMLFrame* aMathMLFrame;
nsresult rv = childFrame->QueryInterface(nsIMathMLFrame::GetIID(), (void**)&aMathMLFrame);
if (NS_SUCCEEDED(rv) && aMathMLFrame) {
// retrieve the metrics that was stored at the ReflowChildren pass
childFrame->GetRect(rect);
nsStretchMetrics childSize(rect.x, rect.y, rect.width, rect.height);
aMathMLFrame->Stretch(aPresContext, aRenderingContext,
aStretchDirection, aContainerSize, childSize);
// store the updated metrics
childFrame->SetRect(aPresContext,
nsRect(childSize.descent, childSize.ascent,
childSize.width, childSize.height));
}
}
childFrame->GetNextSibling(&childFrame);
}
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::Reflow(nsIPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
nsresult rv = NS_OK;
/////////////
// Reflow children
ReflowChildren(0, aPresContext, aDesiredSize, aReflowState, aStatus);
/////////////
// If we are a container which is entitled to stretch its children, then we
// ask our stretchy children to stretch themselves
nsIRenderingContext& renderingContext = *aReflowState.rendContext;
if (NS_MATHML_WILL_STRETCH_ALL_CHILDREN(mEmbellishData.flags)) {
nsStretchMetrics containerSize(aDesiredSize);
nsStretchDirection stretchDir = NS_STRETCH_DIRECTION_VERTICAL;
StretchChildren(aPresContext, renderingContext, stretchDir, containerSize);
}
/////////////
// Place children now by re-adjusting the origins to align the baselines
FinalizeReflow(0, aPresContext, renderingContext, aDesiredSize);
aStatus = NS_FRAME_COMPLETE;
return NS_OK;
}
NS_IMETHODIMP
nsMathMLContainerFrame::Place(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
PRBool aPlaceOrigin,
nsHTMLReflowMetrics& aDesiredSize)
{
aDesiredSize.width = aDesiredSize.height = aDesiredSize.ascent = aDesiredSize.descent = 0;
PRInt32 count = 0;
nsRect rect;
nsIFrame* childFrame = mFrames.FirstChild();
while (childFrame) {
if (!IsOnlyWhitespace(childFrame)) {
childFrame->GetRect(rect);
aDesiredSize.width += rect.width;
if (aDesiredSize.descent < rect.x) aDesiredSize.descent = rect.x;
if (aDesiredSize.ascent < rect.y) aDesiredSize.ascent = rect.y;
// Compute and cache our bounding metrics
nsBoundingMetrics bm;
if (NS_FAILED(GetBoundingMetricsFor(childFrame, bm))) {
bm.ascent = rect.y;
bm.descent = -rect.x;
bm.width = rect.width;
}
if (0 == count)
mBoundingMetrics = bm;
else
mBoundingMetrics += bm;
count++;
}
childFrame->GetNextSibling(&childFrame);
}
aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent;
if (aPlaceOrigin) {
nscoord dy;
nscoord dx = 0;
childFrame = mFrames.FirstChild();
while (childFrame) {
childFrame->GetRect(rect);
nsHTMLReflowMetrics childSize(nsnull);
childSize.width = rect.width;
childSize.height = rect.height;
// Place and size the child
dy = aDesiredSize.ascent - rect.y;
FinishReflowChild(childFrame, aPresContext, childSize, dx, dy, 0);
dx += rect.width;
childFrame->GetNextSibling(&childFrame);
}
}
return NS_OK;
}
//==========================
// *BEWARE* of the wrapper frame!
// This is the frame that is inserted to alter the style context of
// scripting elements. What this means is that looking for your parent
// or your siblings with (possible several) wrapper frames around you
// can make you wonder what is going on. For example, the direct parent
// of the subscript within <msub> is not <msub>, but instead the wrapper
// frame that was insterted to alter the style context of the subscript!
// You will seldom need to find out who is exactly your parent. You should
// first rethink your code to see if you can avoid finding who is your parent.
// Be careful, there are wrapper frames all over the place, and probably
// one or many are wrapping you if you are in a position where the
// scriptlevel is non zero.
nsresult
NS_NewMathMLWrapperFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame)
{
NS_PRECONDITION(aNewFrame, "null OUT ptr");
if (nsnull == aNewFrame) {
return NS_ERROR_NULL_POINTER;
}
nsMathMLWrapperFrame* it = new (aPresShell) nsMathMLWrapperFrame;
if (nsnull == it) {
return NS_ERROR_OUT_OF_MEMORY;
}
*aNewFrame = it;
return NS_OK;
}
nsMathMLWrapperFrame::nsMathMLWrapperFrame()
{
}
nsMathMLWrapperFrame::~nsMathMLWrapperFrame()
{
}
// For Reflow() and Place(), pretend we are a token to re-use code
NS_IMETHODIMP
nsMathMLWrapperFrame::Reflow(nsIPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
return ReflowTokenFor(this, aPresContext, aDesiredSize,
aReflowState, aStatus);
}
NS_IMETHODIMP
nsMathMLWrapperFrame::Place(nsIPresContext* aPresContext,
nsIRenderingContext& aRenderingContext,
PRBool aPlaceOrigin,
nsHTMLReflowMetrics& aDesiredSize)
{
return PlaceTokenFor(this, aPresContext, aRenderingContext,
aPlaceOrigin, aDesiredSize);
}