Home | History | Annotate | Download | only in rendering 
      1 /*
      2  * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org)
      3  *           (C) 1999 Antti Koivisto (koivisto (at) kde.org)
      4  *           (C) 2000 Dirk Mueller (mueller (at) kde.org)
      5  * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.
      6  *
      7  * This library is free software; you can redistribute it and/or
      8  * modify it under the terms of the GNU Library General Public
      9  * License as published by the Free Software Foundation; either
     10  * version 2 of the License, or (at your option) any later version.
     11  *
     12  * This library is distributed in the hope that it will be useful,
     13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     15  * Library General Public License for more details.
     16  *
     17  * You should have received a copy of the GNU Library General Public License
     18  * along with this library; see the file COPYING.LIB.  If not, write to
     19  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     20  * Boston, MA 02110-1301, USA.
     21  *
     22  */
     23 
     24 #include "config.h"
     25 #include "core/rendering/RenderFieldset.h"
     26 
     27 #include "CSSPropertyNames.h"
     28 #include "HTMLNames.h"
     29 #include "core/platform/graphics/GraphicsContextStateSaver.h"
     30 #include "core/rendering/PaintInfo.h"
     31 
     32 using std::min;
     33 using std::max;
     34 
     35 namespace WebCore {
     36 
     37 using namespace HTMLNames;
     38 
     39 RenderFieldset::RenderFieldset(Element* element)
     40     : RenderBlock(element)
     41 {
     42 }
     43 
     44 void RenderFieldset::computePreferredLogicalWidths()
     45 {
     46     RenderBlock::computePreferredLogicalWidths();
     47     if (RenderBox* legend = findLegend()) {
     48         int legendMinWidth = legend->minPreferredLogicalWidth();
     49 
     50         Length legendMarginLeft = legend->style()->marginLeft();
     51         Length legendMarginRight = legend->style()->marginLeft();
     52 
     53         if (legendMarginLeft.isFixed())
     54             legendMinWidth += legendMarginLeft.value();
     55 
     56         if (legendMarginRight.isFixed())
     57             legendMinWidth += legendMarginRight.value();
     58 
     59         m_minPreferredLogicalWidth = max(m_minPreferredLogicalWidth, legendMinWidth + borderAndPaddingWidth());
     60     }
     61 }
     62 
     63 RenderObject* RenderFieldset::layoutSpecialExcludedChild(bool relayoutChildren)
     64 {
     65     RenderBox* legend = findLegend();
     66     if (legend) {
     67         if (relayoutChildren)
     68             legend->setNeedsLayout();
     69         legend->layoutIfNeeded();
     70 
     71         LayoutUnit logicalLeft;
     72         if (style()->isLeftToRightDirection()) {
     73             switch (legend->style()->textAlign()) {
     74             case CENTER:
     75                 logicalLeft = (logicalWidth() - logicalWidthForChild(legend)) / 2;
     76                 break;
     77             case RIGHT:
     78                 logicalLeft = logicalWidth() - borderEnd() - paddingEnd() - logicalWidthForChild(legend);
     79                 break;
     80             default:
     81                 logicalLeft = borderStart() + paddingStart() + marginStartForChild(legend);
     82                 break;
     83             }
     84         } else {
     85             switch (legend->style()->textAlign()) {
     86             case LEFT:
     87                 logicalLeft = borderStart() + paddingStart();
     88                 break;
     89             case CENTER: {
     90                 // Make sure that the extra pixel goes to the end side in RTL (since it went to the end side
     91                 // in LTR).
     92                 LayoutUnit centeredWidth = logicalWidth() - logicalWidthForChild(legend);
     93                 logicalLeft = centeredWidth - centeredWidth / 2;
     94                 break;
     95             }
     96             default:
     97                 logicalLeft = logicalWidth() - borderStart() - paddingStart() - marginStartForChild(legend) - logicalWidthForChild(legend);
     98                 break;
     99             }
    100         }
    101 
    102         setLogicalLeftForChild(legend, logicalLeft);
    103 
    104         LayoutUnit fieldsetBorderBefore = borderBefore();
    105         LayoutUnit legendLogicalHeight = logicalHeightForChild(legend);
    106 
    107         LayoutUnit legendLogicalTop;
    108         LayoutUnit collapsedLegendExtent;
    109         // FIXME: We need to account for the legend's margin before too.
    110         if (fieldsetBorderBefore > legendLogicalHeight) {
    111             // The <legend> is smaller than the associated fieldset before border
    112             // so the latter determines positioning of the <legend>. The sizing depends
    113             // on the legend's margins as we want to still follow the author's cues.
    114             // Firefox completely ignores the margins in this case which seems wrong.
    115             legendLogicalTop = (fieldsetBorderBefore - legendLogicalHeight) / 2;
    116             collapsedLegendExtent = max<LayoutUnit>(fieldsetBorderBefore, legendLogicalTop + legendLogicalHeight + marginAfterForChild(legend));
    117         } else
    118             collapsedLegendExtent = legendLogicalHeight + marginAfterForChild(legend);
    119 
    120         setLogicalTopForChild(legend, legendLogicalTop);
    121         setLogicalHeight(paddingBefore() + collapsedLegendExtent);
    122     }
    123     return legend;
    124 }
    125 
    126 RenderBox* RenderFieldset::findLegend(FindLegendOption option) const
    127 {
    128     for (RenderObject* legend = firstChild(); legend; legend = legend->nextSibling()) {
    129         if (option == IgnoreFloatingOrOutOfFlow && legend->isFloatingOrOutOfFlowPositioned())
    130             continue;
    131 
    132         if (legend->node() && (legend->node()->hasTagName(legendTag)))
    133             return toRenderBox(legend);
    134     }
    135     return 0;
    136 }
    137 
    138 void RenderFieldset::paintBoxDecorations(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
    139 {
    140     if (!paintInfo.shouldPaintWithinRoot(this))
    141         return;
    142 
    143     LayoutRect paintRect(paintOffset, size());
    144     RenderBox* legend = findLegend();
    145     if (!legend)
    146         return RenderBlock::paintBoxDecorations(paintInfo, paintOffset);
    147 
    148     // FIXME: We need to work with "rl" and "bt" block flow directions.  In those
    149     // cases the legend is embedded in the right and bottom borders respectively.
    150     // https://bugs.webkit.org/show_bug.cgi?id=47236
    151     if (style()->isHorizontalWritingMode()) {
    152         LayoutUnit yOff = (legend->y() > 0) ? LayoutUnit() : (legend->height() - borderTop()) / 2;
    153         paintRect.setHeight(paintRect.height() - yOff);
    154         paintRect.setY(paintRect.y() + yOff);
    155     } else {
    156         LayoutUnit xOff = (legend->x() > 0) ? LayoutUnit() : (legend->width() - borderLeft()) / 2;
    157         paintRect.setWidth(paintRect.width() - xOff);
    158         paintRect.setX(paintRect.x() + xOff);
    159     }
    160 
    161     if (!boxShadowShouldBeAppliedToBackground(determineBackgroundBleedAvoidance(paintInfo.context)))
    162         paintBoxShadow(paintInfo, paintRect, style(), Normal);
    163     paintFillLayers(paintInfo, resolveColor(CSSPropertyBackgroundColor), style()->backgroundLayers(), paintRect);
    164     paintBoxShadow(paintInfo, paintRect, style(), Inset);
    165 
    166     if (!style()->hasBorder())
    167         return;
    168 
    169     // Create a clipping region around the legend and paint the border as normal
    170     GraphicsContext* graphicsContext = paintInfo.context;
    171     GraphicsContextStateSaver stateSaver(*graphicsContext);
    172 
    173     // FIXME: We need to work with "rl" and "bt" block flow directions.  In those
    174     // cases the legend is embedded in the right and bottom borders respectively.
    175     // https://bugs.webkit.org/show_bug.cgi?id=47236
    176     if (style()->isHorizontalWritingMode()) {
    177         LayoutUnit clipTop = paintRect.y();
    178         LayoutUnit clipHeight = max(static_cast<LayoutUnit>(style()->borderTopWidth()), legend->height() - ((legend->height() - borderTop()) / 2));
    179         graphicsContext->clipOut(pixelSnappedIntRect(paintRect.x() + legend->x(), clipTop, legend->width(), clipHeight));
    180     } else {
    181         LayoutUnit clipLeft = paintRect.x();
    182         LayoutUnit clipWidth = max(static_cast<LayoutUnit>(style()->borderLeftWidth()), legend->width());
    183         graphicsContext->clipOut(pixelSnappedIntRect(clipLeft, paintRect.y() + legend->y(), clipWidth, legend->height()));
    184     }
    185 
    186     paintBorder(paintInfo, paintRect, style());
    187 }
    188 
    189 void RenderFieldset::paintMask(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
    190 {
    191     if (style()->visibility() != VISIBLE || paintInfo.phase != PaintPhaseMask)
    192         return;
    193 
    194     LayoutRect paintRect = LayoutRect(paintOffset, size());
    195     RenderBox* legend = findLegend();
    196     if (!legend)
    197         return RenderBlock::paintMask(paintInfo, paintOffset);
    198 
    199     // FIXME: We need to work with "rl" and "bt" block flow directions.  In those
    200     // cases the legend is embedded in the right and bottom borders respectively.
    201     // https://bugs.webkit.org/show_bug.cgi?id=47236
    202     if (style()->isHorizontalWritingMode()) {
    203         LayoutUnit yOff = (legend->y() > 0) ? LayoutUnit() : (legend->height() - borderTop()) / 2;
    204         paintRect.expand(0, -yOff);
    205         paintRect.move(0, yOff);
    206     } else {
    207         LayoutUnit xOff = (legend->x() > 0) ? LayoutUnit() : (legend->width() - borderLeft()) / 2;
    208         paintRect.expand(-xOff, 0);
    209         paintRect.move(xOff, 0);
    210     }
    211 
    212     paintMaskImages(paintInfo, paintRect);
    213 }
    214 
    215 } // namespace WebCore
    216