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      1 /*
      2  * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org)
      3  *           (C) 1999 Antti Koivisto (koivisto (at) kde.org)
      4  * Copyright (C) 2004, 2005, 2006, 2009, 2011 Apple Inc. All rights reserved.
      5  *
      6  * This library is free software; you can redistribute it and/or
      7  * modify it under the terms of the GNU Library General Public
      8  * License as published by the Free Software Foundation; either
      9  * version 2 of the License, or (at your option) any later version.
     10  *
     11  * This library is distributed in the hope that it will be useful,
     12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14  * Library General Public License for more details.
     15  *
     16  * You should have received a copy of the GNU Library General Public License
     17  * along with this library; see the file COPYING.LIB.  If not, write to
     18  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
     19  * Boston, MA 02110-1301, USA.
     20  */
     21 
     22 #include "config.h"
     23 #include "core/html/HTMLAreaElement.h"
     24 
     25 #include "core/HTMLNames.h"
     26 #include "core/html/HTMLImageElement.h"
     27 #include "core/html/HTMLMapElement.h"
     28 #include "core/rendering/HitTestResult.h"
     29 #include "core/rendering/RenderImage.h"
     30 #include "core/rendering/RenderView.h"
     31 #include "platform/LengthFunctions.h"
     32 #include "platform/graphics/Path.h"
     33 #include "platform/transforms/AffineTransform.h"
     34 
     35 namespace blink {
     36 
     37 using namespace HTMLNames;
     38 
     39 inline HTMLAreaElement::HTMLAreaElement(Document& document)
     40     : HTMLAnchorElement(areaTag, document)
     41     , m_lastSize(-1, -1)
     42     , m_shape(Unknown)
     43 {
     44 }
     45 
     46 DEFINE_NODE_FACTORY(HTMLAreaElement)
     47 
     48 void HTMLAreaElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
     49 {
     50     if (name == shapeAttr) {
     51         if (equalIgnoringCase(value, "default"))
     52             m_shape = Default;
     53         else if (equalIgnoringCase(value, "circle"))
     54             m_shape = Circle;
     55         else if (equalIgnoringCase(value, "poly"))
     56             m_shape = Poly;
     57         else if (equalIgnoringCase(value, "rect"))
     58             m_shape = Rect;
     59         invalidateCachedRegion();
     60     } else if (name == coordsAttr) {
     61         m_coords = parseHTMLAreaElementCoords(value.string());
     62         invalidateCachedRegion();
     63     } else if (name == altAttr || name == accesskeyAttr) {
     64         // Do nothing.
     65     } else
     66         HTMLAnchorElement::parseAttribute(name, value);
     67 }
     68 
     69 void HTMLAreaElement::invalidateCachedRegion()
     70 {
     71     m_lastSize = LayoutSize(-1, -1);
     72 }
     73 
     74 bool HTMLAreaElement::mapMouseEvent(LayoutPoint location, const LayoutSize& size, HitTestResult& result)
     75 {
     76     if (m_lastSize != size) {
     77         m_region = adoptPtr(new Path(getRegion(size)));
     78         m_lastSize = size;
     79     }
     80 
     81     if (!m_region->contains(location))
     82         return false;
     83 
     84     result.setInnerNode(this);
     85     result.setURLElement(this);
     86     return true;
     87 }
     88 
     89 Path HTMLAreaElement::computePath(RenderObject* obj) const
     90 {
     91     if (!obj)
     92         return Path();
     93 
     94     // FIXME: This doesn't work correctly with transforms.
     95     FloatPoint absPos = obj->localToAbsolute();
     96 
     97     // Default should default to the size of the containing object.
     98     LayoutSize size = m_lastSize;
     99     if (m_shape == Default)
    100         size = obj->absoluteClippedOverflowRect().size();
    101 
    102     Path p = getRegion(size);
    103     float zoomFactor = obj->style()->effectiveZoom();
    104     if (zoomFactor != 1.0f) {
    105         AffineTransform zoomTransform;
    106         zoomTransform.scale(zoomFactor);
    107         p.transform(zoomTransform);
    108     }
    109 
    110     p.translate(toFloatSize(absPos));
    111     return p;
    112 }
    113 
    114 LayoutRect HTMLAreaElement::computeRect(RenderObject* obj) const
    115 {
    116     return enclosingLayoutRect(computePath(obj).boundingRect());
    117 }
    118 
    119 Path HTMLAreaElement::getRegion(const LayoutSize& size) const
    120 {
    121     if (m_coords.isEmpty() && m_shape != Default)
    122         return Path();
    123 
    124     LayoutUnit width = size.width();
    125     LayoutUnit height = size.height();
    126 
    127     // If element omits the shape attribute, select shape based on number of coordinates.
    128     Shape shape = m_shape;
    129     if (shape == Unknown) {
    130         if (m_coords.size() == 3)
    131             shape = Circle;
    132         else if (m_coords.size() == 4)
    133             shape = Rect;
    134         else if (m_coords.size() >= 6)
    135             shape = Poly;
    136     }
    137 
    138     Path path;
    139     switch (shape) {
    140         case Poly:
    141             if (m_coords.size() >= 6) {
    142                 int numPoints = m_coords.size() / 2;
    143                 path.moveTo(FloatPoint(minimumValueForLength(m_coords[0], width).toFloat(), minimumValueForLength(m_coords[1], height).toFloat()));
    144                 for (int i = 1; i < numPoints; ++i)
    145                     path.addLineTo(FloatPoint(minimumValueForLength(m_coords[i * 2], width).toFloat(), minimumValueForLength(m_coords[i * 2 + 1], height).toFloat()));
    146                 path.closeSubpath();
    147             }
    148             break;
    149         case Circle:
    150             if (m_coords.size() >= 3) {
    151                 Length radius = m_coords[2];
    152                 float r = std::min(minimumValueForLength(radius, width).toFloat(), minimumValueForLength(radius, height).toFloat());
    153                 path.addEllipse(FloatRect(minimumValueForLength(m_coords[0], width).toFloat() - r, minimumValueForLength(m_coords[1], height).toFloat() - r, 2 * r, 2 * r));
    154             }
    155             break;
    156         case Rect:
    157             if (m_coords.size() >= 4) {
    158                 float x0 = minimumValueForLength(m_coords[0], width).toFloat();
    159                 float y0 = minimumValueForLength(m_coords[1], height).toFloat();
    160                 float x1 = minimumValueForLength(m_coords[2], width).toFloat();
    161                 float y1 = minimumValueForLength(m_coords[3], height).toFloat();
    162                 path.addRect(FloatRect(x0, y0, x1 - x0, y1 - y0));
    163             }
    164             break;
    165         case Default:
    166             path.addRect(FloatRect(0, 0, width.toFloat(), height.toFloat()));
    167             break;
    168         case Unknown:
    169             break;
    170     }
    171 
    172     return path;
    173 }
    174 
    175 HTMLImageElement* HTMLAreaElement::imageElement() const
    176 {
    177     if (HTMLMapElement* mapElement = Traversal<HTMLMapElement>::firstAncestor(*this))
    178         return mapElement->imageElement();
    179     return 0;
    180 }
    181 
    182 bool HTMLAreaElement::isKeyboardFocusable() const
    183 {
    184     return isFocusable();
    185 }
    186 
    187 bool HTMLAreaElement::isMouseFocusable() const
    188 {
    189     return isFocusable();
    190 }
    191 
    192 bool HTMLAreaElement::rendererIsFocusable() const
    193 {
    194     HTMLImageElement* image = imageElement();
    195     if (!image || !image->renderer() || image->renderer()->style()->visibility() != VISIBLE)
    196         return false;
    197 
    198     return supportsFocus() && Element::tabIndex() >= 0;
    199 }
    200 
    201 void HTMLAreaElement::setFocus(bool shouldBeFocused)
    202 {
    203     if (focused() == shouldBeFocused)
    204         return;
    205 
    206     HTMLAnchorElement::setFocus(shouldBeFocused);
    207 
    208     HTMLImageElement* imageElement = this->imageElement();
    209     if (!imageElement)
    210         return;
    211 
    212     RenderObject* renderer = imageElement->renderer();
    213     if (!renderer || !renderer->isImage())
    214         return;
    215 
    216     toRenderImage(renderer)->areaElementFocusChanged(this);
    217 }
    218 
    219 void HTMLAreaElement::updateFocusAppearance(bool restorePreviousSelection)
    220 {
    221     if (!isFocusable())
    222         return;
    223 
    224     HTMLImageElement* imageElement = this->imageElement();
    225     if (!imageElement)
    226         return;
    227 
    228     imageElement->updateFocusAppearance(restorePreviousSelection);
    229 }
    230 
    231 }
    232