Adding the prototype GF editor for simple multilingual grammars

src/editor/simple/slideshow.js

@@ -0,0 +1,86 @@
+
+var internet_explorer=navigator.appName=="Microsoft Internet Explorer";
+
+/* How to change opacity in IE:
+http://joseph.randomnetworks.com/archives/2006/08/16/css-opacity-in-internet-explorer-ie/
+*/
+
+var set_opacity =
+  internet_explorer
+    ? function(el,o) { el.style.filter="alpha(opacity="+Math.round(o*100)+")";}
+    : function(el,o) { el.style.opacity=o; };
+
+function start_slideshow(img,options) {
+    var p=img.parentNode;
+    if(p.tagName=="A") p=p.parentNode;
+    var is=p.getElementsByTagName("img");
+    if(is.length>1) {
+	var cur=0;
+	var w=img.width;
+	var h=img.height;
+	//p.style.position="relative";
+	p.style.minWidth=w+"px";
+	p.style.minHeight=h+"px";
+	var images=[];
+	for(var i=0;i<is.length;i++) {
+	    images[i]=is[i];
+	    var c=images[i];
+	    if(internet_explorer) c.style.zoom=1;
+	    c.style.position="absolute";
+	}
+	var timeout=1000*(options.delay || 5);
+	var ft=options.fade==null ? 1 : options.fade;
+	var tick=function() {
+	    var c=images[cur];
+	    cur= (cur+1) % images.length;
+	    var n=images[cur];
+	    set_opacity(n,0);
+	    //n.style.position="static";
+	    n.style.zIndex=1;
+	    n.className="";
+	    if(n.width>w) { w=n.width; p.style.minWidth=w+"px"; }
+	    if(n.height>h) { h=n.height; p.style.minHeight=h+"px"; }
+	    c.style.position="absolute";
+	    c.style.zIndex=0;
+	    fade(n,0,1,ft,function() {
+		if(c.width>n.width || c.height>n.height) fade(c,1,0,ft,null);
+		else set_opacity(c,0); });
+	    //debug.innerHTML=w+"x"+h;
+	    //for(var i=0;i<images.length;i++)
+		//debug.appendChild(text(" "+images[i].style.position));
+	}
+	//var debug=document.createElement("div");
+	//p.parentNode.insertBefore(debug,p);
+	//debug.innerHTML=w+"x"+h;
+	setInterval(tick,timeout);
+    }
+    //else alert("No slideshow!");
+}
+
+function fade(el,start,stop,t,after) {
+  // el: which element to fade
+  // start: starting opacity [0..1]
+  // stop: ending opacity [0..1]
+  // t: duration of fade (in seconds), default 1s
+  // after: function to call when done fading, optional
+  var dt=40; // Animation granularity, 1/40ms = 25fps
+  el.step=(stop-start)*dt/(1000*(t==null ? 1 : t));
+  el.stop=stop;
+  //alert("fade "+start+" "+stop+" "+el.step);
+  var done=function() {
+      clearInterval(el.timer);
+      el.timer=null;
+      if(after) after();
+  }
+  var f=function() {
+     var next=el.current+el.step;
+     if(next>=1) { next=1; done(); }
+     if(next<=0) { next=0; done(); }
+     set_opacity(el,next);
+     el.current=next
+  }
+  if(!el.timer) {
+      el.current=start;
+      el.timer=setInterval(f,dt);
+  }
+}