<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.0//EN" 
  "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">


<!--

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (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.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

-->
<svg width="655" height="600" viewBox="0 0 655 600"
     xmlns="http://www.w3.org/2000/svg" 
     xmlns:xlink="http://www.w3.org/1999/xlink" >

<script type="text/ecmascript">
<![CDATA[
var svgns   = "http://www.w3.org/2000/svg";
var xlinkns = "http://www.w3.org/1999/xlink";

var SCALE="scale";
var DRAG="drag";

var action, actionNode, actionTgt;
var dx, dy;
var imgGroup = document.getElementById("imgGroup")
var filter   = imgGroup.getAttribute("style");
var dragged=false;

function dragOn(evt) {
  actionNode = evt.target;
  action = DRAG;
  var currX = parseFloat(actionNode.getAttribute("x"));
  var currY = parseFloat(actionNode.getAttribute("y"));
  var nowToX = evt.clientX;
  var nowToY = evt.clientY;

  // handle the current zoom and pan
  var trans = document.documentElement.currentTranslate;
  var scale = document.documentElement.currentScale;
  nowToX = (nowToX - trans.x) / scale;
  nowToY = (nowToY - trans.y) / scale;

  dx = nowToX-currX;
  dy = nowToY-currY;
  dragged=false;
}

function scaleOn(evt) {
  actionNode = actionTgt;
  action = SCALE;
  var cW = parseFloat(actionNode.getAttribute("width"));
  var cH = parseFloat(actionNode.getAttribute("height"));
  var nowToX = evt.clientX;
  var nowToY = evt.clientY;

  // handle the current zoom and pan
  var trans = document.documentElement.currentTranslate;
  var scale = document.documentElement.currentScale;
  nowToX = (nowToX - trans.x) / scale;
  nowToY = (nowToY - trans.y) / scale;

  dx = nowToX-cW;
  dy = nowToY-cH;
  dragged=false;
}

function dragScaleOff() {
  if (dragged) imgGroup.setAttribute("style",filter);

  if (actionNode != null) {
    if (actionNode != imgGroup.lastChild) {
       imgGroup.appendChild(actionNode);
    }
    actionNode = null;
  }
}

function dragScaleImgBg(evt) {
  if (actionNode == null) {
        hideOverlay();
        return;
  }
  dragScaleImg(evt);
}

function dragScaleImg(evt) {
  if (actionNode == null) return;

  dragged = true;
  imgGroup.setAttribute("style","");
  if (actionNode != imgGroup.lastChild) 
      imgGroup.appendChild(actionNode);

  var nowToX = evt.clientX;
  var nowToY = evt.clientY;

  // handle the current zoom and pan
  var trans = document.documentElement.currentTranslate;
  var scale = document.documentElement.currentScale;
  nowToX = (nowToX - trans.x) / scale;
  nowToY = (nowToY - trans.y) / scale;

  if (action == DRAG) {
    actionNode.setAttribute("x",""+(nowToX-dx));
    actionNode.setAttribute("y",""+(nowToY-dy));
  } else {
    var cW = parseFloat(actionNode.getAttribute("width"));
    var cH = parseFloat(actionNode.getAttribute("height"));

    var ar = cW/cH; 
    var nW = nowToX-dx;
    var nH = nowToY-dy;

    if (nW/nH < ar) { nW = ar*nH; }
    else            { nH = nW/ar; }

    actionNode.setAttribute("width", ""+nW);
    actionNode.setAttribute("height",""+nH);
  }

  updateOverlay(actionNode);
}

function updateOverlay(tgt) {
  var cX = parseFloat(tgt.getAttribute("x"));
  var cY = parseFloat(tgt.getAttribute("y"));
  var cW = parseFloat(tgt.getAttribute("width"));
  var cH = parseFloat(tgt.getAttribute("height"));

  var over = document.getElementById("overlay");
  over.setAttribute("transform","translate("+(cX+cW-1)+","+(cY+cH-1)+")");
  actionTgt = tgt;
}

function showOverlay(evt) {
  if (actionNode != null) return;
  updateOverlay(evt.target);
  document.getElementById("overlay").setAttribute("visibility","visible");
}

function hideOverlay() {
  if (actionNode != null) return;
  document.getElementById("overlay").setAttribute("visibility","hidden");
  actionTgt=null;
}
 ]]></script>

   <filter id="merge"  filterUnits="objectBoundingBox" >
       <feMorphology operator="dilate" radius="10" in="SourceAlpha" />
       <feGaussianBlur stdDeviation="4" /> 
       <feOffset dx="3" dy="3"/>
       <feComponentTransfer result="shadow">
          <feFuncA type="linear" slope=".6" intercept="0" />
       </feComponentTransfer>
       <feComposite operator="over" in="SourceGraphic" in2="shadow"/>
   </filter>

   <rect fill="#88A" x="0%" y="0%" width="100%" height="100%"/>
   <text x="302" y="47" font-size="24" fill="#448"
        >Click and drag to move images</text>
   <text x="300" y="45" font-size="24" fill="white"
        >Click and drag to move images</text>
   <rect fill="none" x="0%" y="0%" width="100%" height="100%"
         pointer-events="fill"
         onmousedown="dragScaleOff()"
         onmouseup="dragScaleOff()"
         onmousemove="dragScaleImgBg(evt)"/>

   <g id="imgGroup" style="filter:url(#merge)" 
             onmousedown="dragOn(evt)"
             onmouseup="dragScaleOff()"
             onmousemove="dragScaleImg(evt)"
             onmouseover="showOverlay(evt)">

      <image x="25" y="315" width="360" height="240"
             xlink:href="tests/resources/images/operaSteps.jpg"/>
   
      <image x="50" y="40" width="200" height="300"
             xlink:href="tests/resources/images/operaWalk.jpg"/>
   
      <image x="270" y="200" width="360" height="240"
             xlink:href="tests/resources/images/operaBridge.jpg"/>
   </g>

   <g id="overlay" visibility="hidden" 
      onmousedown="scaleOn(evt)"
      onmouseup="dragScaleOff()"
      onmousemove="dragScaleImg(evt)">
      <path fill="darkgrey" stroke="white"
            d="M0,0 h-20 l20,-20 z M-12,-3 l9-9 z M-6,-3 l3-3z"/>
   </g>

</svg>