/* * 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 * David J. Fiddes * Shyjan Mahamud (added TeX rendering rules) */ #include "nsCOMPtr.h" #include "nsHTMLParts.h" #include "nsIHTMLContent.h" #include "nsFrame.h" #include "nsLineLayout.h" #include "nsHTMLIIDs.h" #include "nsIPresContext.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 "nsMathMLmsupFrame.h" // // -- attach a superscript to a base - implementation // nsresult NS_NewMathMLmsupFrame(nsIPresShell* aPresShell, nsIFrame** aNewFrame) { NS_PRECONDITION(aNewFrame, "null OUT ptr"); if (nsnull == aNewFrame) { return NS_ERROR_NULL_POINTER; } nsMathMLmsupFrame* it = new (aPresShell) nsMathMLmsupFrame; if (nsnull == it) { return NS_ERROR_OUT_OF_MEMORY; } *aNewFrame = it; return NS_OK; } nsMathMLmsupFrame::nsMathMLmsupFrame() { } nsMathMLmsupFrame::~nsMathMLmsupFrame() { } NS_IMETHODIMP nsMathMLmsupFrame::Init(nsIPresContext* aPresContext, nsIContent* aContent, nsIFrame* aParent, nsIStyleContext* aContext, nsIFrame* aPrevInFlow) { nsresult rv = nsMathMLContainerFrame::Init (aPresContext, aContent, aParent, aContext, aPrevInFlow); mSupScriptShiftFactor = 0.0f; mScriptSpace = NSFloatPointsToTwips(0.5f); // 0.5pt as in plain TeX // check for superscriptshift attribute in ex units nsAutoString value; mUserSetFlag = PR_FALSE; if (NS_CONTENT_ATTR_HAS_VALUE == mContent->GetAttribute (kNameSpaceID_None, nsMathMLAtoms::superscriptshift_, value)) { PRInt32 aErrorCode; float aUserValue = value.ToFloat(&aErrorCode); if (NS_SUCCEEDED(aErrorCode)) { mUserSetFlag = PR_TRUE; mSupScriptShiftFactor = aUserValue; } } return rv; } NS_IMETHODIMP nsMathMLmsupFrame::Place(nsIPresContext* aPresContext, nsIRenderingContext& aRenderingContext, PRBool aPlaceOrigin, nsHTMLReflowMetrics& aDesiredSize) { nsresult rv = NS_OK; //////////////////////////////////// // Get the children's desired sizes PRInt32 count = 0; nsRect aRect; nsHTMLReflowMetrics baseSize (nsnull); nsHTMLReflowMetrics supScriptSize (nsnull); nsIFrame* baseFrame; nsIFrame* supScriptFrame; // parameter u in Rule 18a, Appendix G of the TeXbook nscoord minSupScriptShift = 0; nsBoundingMetrics bmBase, bmSupScript; nsIFrame* aChildFrame = mFrames.FirstChild(); while (nsnull != aChildFrame) { if (!IsOnlyWhitespace(aChildFrame)) { aChildFrame->GetRect(aRect); if (0 == count) { // base baseFrame = aChildFrame; baseSize.descent = aRect.x; baseSize.ascent = aRect.y; baseSize.width = aRect.width; baseSize.height = aRect.height; if (NS_FAILED(GetBoundingMetricsFor(baseFrame, bmBase))) { bmBase.descent = baseSize.descent; bmBase.ascent = baseSize.ascent; bmBase.width = baseSize.width; } } else if (1 == count) { // superscript supScriptFrame = aChildFrame; supScriptSize.descent = aRect.x; supScriptSize.ascent = aRect.y; supScriptSize.width = aRect.width; supScriptSize.height = aRect.height; if (NS_FAILED(GetBoundingMetricsFor(supScriptFrame, bmSupScript))) { bmSupScript.descent = supScriptSize.descent; bmSupScript.ascent = supScriptSize.ascent; bmSupScript.width = supScriptSize.width; } // get the supdrop from the supscript font nscoord aSupDrop; GetSupDropFromChild (aPresContext, supScriptFrame, aSupDrop); // parameter u, Rule 18a, App. G, TeXbook minSupScriptShift = bmBase.ascent - aSupDrop; } else { NS_ASSERTION((count < 2),"nsMathMLmsupFrame : invalid markup"); } count++; } rv = aChildFrame->GetNextSibling(&aChildFrame); NS_ASSERTION(NS_SUCCEEDED(rv),"failed to get next child"); } ////////////////// // Place Children // get min supscript shift limit from x-height // = d(x) + 1/4 * sigma_5, Rule 18c, App. G, TeXbook nscoord xHeight = 0; nsCOMPtr fm; const nsStyleFont* aFont = (const nsStyleFont*) mStyleContext->GetStyleData (eStyleStruct_Font); aPresContext->GetMetricsFor (aFont->mFont, getter_AddRefs(fm)); fm->GetXHeight (xHeight); nscoord minShiftFromXHeight = (nscoord) (supScriptSize.descent + (1.0f/4.0f) * xHeight); // aSupScriptShift{1,2,3} // = minimum amount to shift the supscript up // = sup{1,2,3} in TeX // aSupScriptShift1 = superscriptshift attribute * x-height // Note that there are THREE values for supscript shifts depending // on the current style nscoord aSupScriptShift1, aSupScriptShift2, aSupScriptShift3; // Set aSupScriptShift{1,2,3} default from font GetSupScriptShifts (fm, aSupScriptShift1, aSupScriptShift2, aSupScriptShift3); if (mUserSetFlag) { // the user has set the supscriptshift attribute float aFactor2 = ((float) aSupScriptShift2) / aSupScriptShift1; float aFactor3 = ((float) aSupScriptShift3) / aSupScriptShift1; aSupScriptShift1 = NSToCoordRound(mSupScriptShiftFactor * xHeight); aSupScriptShift2 = NSToCoordRound(aFactor2 * aSupScriptShift1); aSupScriptShift3 = NSToCoordRound(aFactor3 * aSupScriptShift1); } // get sup script shift depending on current script level and display style // Rule 18c, App. G, TeXbook nscoord aSupScriptShift; if ( mPresentationData.scriptLevel == 0 && NS_MATHML_IS_DISPLAYSTYLE(mPresentationData.flags) && !NS_MATHML_IS_COMPRESSED(mPresentationData.flags)) { // Style D in TeXbook aSupScriptShift = aSupScriptShift1; } else if (NS_MATHML_IS_COMPRESSED(mPresentationData.flags)) { // Style C' in TeXbook = D',T',S',SS' aSupScriptShift = aSupScriptShift3; } else { // everything else = T,S,SS aSupScriptShift = aSupScriptShift2; } // get actual supscriptshift to be used // Rule 18c, App. G, TeXbook nscoord actualSupScriptShift = PR_MAX(minSupScriptShift,PR_MAX(aSupScriptShift,minShiftFromXHeight)); // get bounding box for base + supscript #if 0 const nsStyleFont *font; baseFrame->GetStyleData(eStyleStruct_Font, (const nsStyleStruct *&)font); PRInt32 baseStyle = font->mFont.style; supScriptFrame->GetStyleData(eStyleStruct_Font, (const nsStyleStruct *&)font); PRInt32 supScriptStyle = font->mFont.style; if (baseStyle == NS_STYLE_FONT_STYLE_ITALIC && supScriptStyle != NS_STYLE_FONT_STYLE_ITALIC) { // take care of italic correction ... } #endif #if 0 aDesiredSize.ascent = PR_MAX(baseSize.ascent,(supScriptSize.ascent+actualSupScriptShift)); aDesiredSize.descent = PR_MAX(baseSize.descent,(supScriptSize.descent-actualSupScriptShift)); aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent; // add mScriptSpace between base and supscript aDesiredSize.width = baseSize.width + mScriptSpace + supScriptSize.width; #endif mBoundingMetrics.ascent = PR_MAX(bmBase.ascent, bmSupScript.ascent + actualSupScriptShift); mBoundingMetrics.descent = PR_MAX(bmBase.descent, bmSupScript.descent - actualSupScriptShift); // add mScriptSpace between base and supscript mBoundingMetrics.width = bmBase.width + mScriptSpace + bmSupScript.width; #if 0 printf("bmBase.width:%d + mScriptSpace:%d + bmSupScript.width:%d = mBoundingMetrics.width:%d\n", bmBase.width, mScriptSpace, bmSupScript.width, mBoundingMetrics.width); #endif aDesiredSize.ascent = PR_MAX(baseSize.ascent, supScriptSize.ascent + actualSupScriptShift); aDesiredSize.descent = PR_MAX(baseSize.descent, supScriptSize.descent - actualSupScriptShift); aDesiredSize.height = aDesiredSize.ascent + aDesiredSize.descent; aDesiredSize.width = baseSize.width + mScriptSpace + supScriptSize.width; if (aPlaceOrigin) { nscoord dx, dy; // now place the base ... dx = 0; dy = aDesiredSize.ascent - baseSize.ascent; FinishReflowChild (baseFrame, aPresContext, baseSize, dx, dy, 0); // ... and supscript #if 0 float t2p; aPresContext->GetTwipsToPixels(&t2p); PRInt32 scriptspace = NSTwipsToIntPixels(mScriptSpace, t2p); printf("mScriptSpace in twips:%d pixel:%d\n", mScriptSpace, scriptspace); #endif dx = baseSize.width + mScriptSpace; dy = aDesiredSize.ascent - supScriptSize.ascent - actualSupScriptShift; FinishReflowChild (supScriptFrame, aPresContext, supScriptSize, dx, dy, 0); } return NS_OK; }