/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- * * The contents of this file are subject to the Netscape Public License * Version 1.0 (the "NPL"); you may not use this file except in * compliance with the NPL. You may obtain a copy of the NPL at * http://www.mozilla.org/NPL/ * * Software distributed under the NPL is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL * for the specific language governing rights and limitations under the * NPL. * * The Initial Developer of this code under the NPL is Netscape * Communications Corporation. Portions created by Netscape are * Copyright (C) 1998 Netscape Communications Corporation. All Rights * Reserved. */ #include "nsCSSLayout.h" #include "nsIStyleContext.h" #include "nsStyleConsts.h" #include "nsIContent.h" #include "nsIFrame.h" #include "nsIFontMetrics.h" #include "nsIPresContext.h" #include "nsRect.h" #include "nsIPtr.h" static NS_DEFINE_IID(kStyleTextSID, NS_STYLETEXT_SID); static NS_DEFINE_IID(kStylePositionSID, NS_STYLEPOSITION_SID); NS_DEF_PTR(nsIStyleContext); NS_DEF_PTR(nsIContent); // XXX what about ebina's center vs. ncsa-center? /* * Notes: It's a known fact that this doesn't do what ebina's layout * engine does because his code did vertical alignment on the * fly. Hopefully that's ok because his code generated surprising * results in a number of unusual cases. */ nscoord nsCSSLayout::VerticallyAlignChildren(nsIPresContext* aCX, nsIFrame* aContainer, nsStyleFont* aContainerFont, nscoord aY0, nsIFrame* aFirstChild, PRIntn aChildCount, nscoord* aAscents, nscoord aMaxAscent) { // Determine minimum and maximum y values for the line and // perform alignment of all children except those requesting bottom // alignment. The second pass will align bottom children (if any) nsIFontMetrics* fm = aCX->GetMetricsFor(aContainerFont->mFont); nsIFrame* kid = aFirstChild; nsRect kidRect; nscoord minY = aY0; nscoord maxY = aY0; PRIntn pass2Kids = 0; PRIntn kidCount = aChildCount; while (--kidCount >= 0) { nscoord kidAscent = *aAscents++; nsIStyleContextPtr kidSC; nsIContentPtr kidContent; kid->GetStyleContext(aCX, kidSC.AssignRef()); kid->GetContent(kidContent.AssignRef()); nsStyleText* textStyle = (nsStyleText*)kidSC->GetData(kStyleTextSID); nsStyleUnit verticalAlignUnit = textStyle->mVerticalAlign.GetUnit(); PRUint8 verticalAlignEnum = NS_STYLE_VERTICAL_ALIGN_BASELINE; kid->GetRect(kidRect); // Vertically align the child nscoord kidYTop = 0; switch (verticalAlignUnit) { case eStyleUnit_Twips: kidYTop = aMaxAscent + textStyle->mVerticalAlign.GetCoordValue(); break; case eStyleUnit_Percent: pass2Kids++; break; case eStyleUnit_Enumerated: verticalAlignEnum = textStyle->mVerticalAlign.GetIntValue(); switch (verticalAlignEnum) { default: case NS_STYLE_VERTICAL_ALIGN_BASELINE: // Align the kid's baseline at the max baseline kidYTop = aMaxAscent - kidAscent; break; case NS_STYLE_VERTICAL_ALIGN_TOP: // Align the top of the kid with the top of the line box break; case NS_STYLE_VERTICAL_ALIGN_SUB: // Move baseline by 1/2 the ascent of the child. // NOTE: CSSx doesn't seem to specify what subscripting does // so we are using ebina's logic kidYTop = aMaxAscent + (kidAscent/2) - kidAscent; break; case NS_STYLE_VERTICAL_ALIGN_SUPER: // Move baseline by 1/2 the ascent of the child // NOTE: CSSx doesn't seem to specify what superscripting does // so we are using ebina's logic kidYTop = aMaxAscent - (kidAscent/2) - kidAscent; break; case NS_STYLE_VERTICAL_ALIGN_BOTTOM: pass2Kids++; break; case NS_STYLE_VERTICAL_ALIGN_MIDDLE: // XXX spec says use the 'x' height but our font api doesn't give us // that information. kidYTop = aMaxAscent - (fm->GetHeight() / 2) - kidRect.height/2; break; case NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM: kidYTop = aMaxAscent + fm->GetMaxDescent() - kidRect.height; break; case NS_STYLE_VERTICAL_ALIGN_TEXT_TOP: kidYTop = aMaxAscent - fm->GetMaxAscent(); break; } break; default: // Align the kid's baseline at the max baseline kidYTop = aMaxAscent - kidAscent; break; } // Place kid and update min and max Y values nscoord y = aY0 + kidYTop; if (y < minY) minY = y; kid->MoveTo(kidRect.x, y); y += kidRect.height; if (y > maxY) maxY = y; kid->GetNextSibling(kid); } nscoord lineHeight = maxY - minY; if (0 != pass2Kids) { // Position all of the bottom aligned children kidCount = aChildCount; kid = aFirstChild; while (--kidCount >= 0) { // Get kid's vertical align style data nsIStyleContextPtr kidSC; nsIContentPtr kidContent; kid->GetStyleContext(aCX, kidSC.AssignRef()); kid->GetContent(kidContent.AssignRef()); nsStyleText* textStyle = (nsStyleText*)kidSC->GetData(kStyleTextSID); nsStyleUnit verticalAlignUnit = textStyle->mVerticalAlign.GetUnit(); if (eStyleUnit_Percent == verticalAlignUnit) { nscoord kidYTop = aMaxAscent + nscoord(textStyle->mVerticalAlign.GetFloatValue() * lineHeight); kid->GetRect(kidRect); kid->MoveTo(kidRect.x, aY0 + kidYTop); if (--pass2Kids == 0) { // Stop on last pass2 kid break; } } else if (verticalAlignUnit == eStyleUnit_Enumerated) { PRUint8 verticalAlignEnum = textStyle->mVerticalAlign.GetIntValue(); // Vertically align the child if (NS_STYLE_VERTICAL_ALIGN_BOTTOM == verticalAlignEnum) { // Place kid along the bottom kid->GetRect(kidRect); kid->MoveTo(kidRect.x, aY0 + lineHeight - kidRect.height); if (--pass2Kids == 0) { // Stop on last pass2 kid break; } } } kid->GetNextSibling(kid); } } NS_RELEASE(fm); return lineHeight; } /** * Horizontally place the children in the container frame. */ void nsCSSLayout::HorizontallyPlaceChildren(nsIPresContext* aCX, nsIFrame* aContainer, nsStyleText* aContainerStyle, nsIFrame* aFirstChild, PRInt32 aChildCount, nscoord aLineWidth, nscoord aMaxWidth) { PRIntn textAlign = aContainerStyle->mTextAlign; nscoord dx = 0; switch (textAlign) { case NS_STYLE_TEXT_ALIGN_LEFT: case NS_STYLE_TEXT_ALIGN_JUSTIFY: // Default layout has everything aligned left return; case NS_STYLE_TEXT_ALIGN_RIGHT: dx = aMaxWidth - aLineWidth; break; case NS_STYLE_TEXT_ALIGN_CENTER: dx = (aMaxWidth - aLineWidth) / 2; break; } // Position children nsPoint origin; nsIFrame* kid = aFirstChild; while (--aChildCount >= 0) { kid->GetOrigin(origin); kid->MoveTo(origin.x + dx, origin.y); kid->GetNextSibling(kid); } } /** * Apply css relative positioning to any child that requires it. */ void nsCSSLayout::RelativePositionChildren(nsIPresContext* aCX, nsIFrame* aContainer, nsIFrame* aFirstChild, PRInt32 aChildCount) { nsPoint origin; nsIFrame* kid = aFirstChild; while (--aChildCount >= 0) { nsIContentPtr kidContent; nsIStyleContextPtr kidSC; kid->GetContent(kidContent.AssignRef()); kid->GetStyleContext(aCX, kidSC.AssignRef()); nsStylePosition* kidPosition = (nsStylePosition*) kidSC->GetData(kStylePositionSID); if (NS_STYLE_POSITION_RELATIVE == kidPosition->mPosition) { kid->GetOrigin(origin); // XXX Check the flags: could be auto or percent (not just length) nscoord dx = kidPosition->mLeftOffset; nscoord dy = kidPosition->mTopOffset; kid->MoveTo(origin.x + dx, origin.y + dy); } kid->GetNextSibling(kid); } }