--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nodejs/animate.js	Tue Aug 17 05:15:50 2010 +0800
@@ -0,0 +1,39 @@
+var sys=require("sys");
+
+function linear_draw() {
+    if (this.end == 1) return;
+    var percent = (Date.now() - this.starttime)/this.duration;
+	if (percent > 1) percent = 1;
+    this.obj[5] = (this.target-this.startpos)*percent+this.startpos;
+	this.app.refresh();
+	var self = this;
+	if (percent < 1) {
+	    this.obj.timer=setTimeout(function() { self.draw();}, 20);
+		return;
+	}
+	this.app.refresh();
+	this.obj.animated_linear = null;
+}
+function linear(app,obj,target,duration) {
+    try {
+        if (obj.animated_linear) {
+	        obj[5] = obj.animated_linear.target;
+			obj.animated_linear.end = 1;
+		}
+	} catch(e) {
+	    
+	}
+	obj.animated_linear = this;
+	this.app = app;
+	this.obj = obj;
+	this.end = 0;
+	this.starttime = Date.now();
+	this.startpos = obj[5];
+    this.target = target;
+	this.duration = duration*1000;
+}
+
+
+exports.linear = linear;
+linear.prototype.start = linear_draw;
+linear.prototype.draw = linear_draw;

--- a/nodejs/testsvg.js	Mon Aug 16 07:34:21 2010 +0800
+++ b/nodejs/testsvg.js	Tue Aug 17 05:15:50 2010 +0800
@@ -1,6 +1,7 @@
 var svg = require("./svg");
 var mbapp = require("./mbapp");
 var sys=require("sys");
+var animate=require("./animate");
 
 app = new mbapp.app();
 app.loadSVG("test.svg");
@@ -8,44 +9,24 @@
 item=1;
 lightbar[5] = app.get("item"+item)[5];
 
-function animated(app,obj) {
-	var d=obj.animated_loc - obj[5];
-	var dd=d;
-	if (dd<0) dd = -dd;
-
-	if (dd > 5) {
-		if (d > 0) d = 5; else d = -5;
-	}
-
-    obj[5] += d;
-	sys.puts(d);
-	app.refresh()
-	if (dd > 1) {
-	    setTimeout(function() { animated(app,obj);}, 20);
-		return;
-	}
-	app.animated_end = 1;
-}
-function animated_start(app,obj,target) {
-    if (obj.animated_end==0)
-	    obj[5] = obj.animated_loc;
-    obj.animated_loc = target[5];
-	obj.animated_end = 0;
-	animated(app,obj);
-}
-lightbar.animated_loc = 1;
 app.addKeyboardListener(mbapp.EVT_KB_PRESS, function(evt) {
     if (evt.keycode == mbapp.KEY_UP) {
 		item = item - 1;
 		if (item == 0) item = 1;
-		else
-            animated_start(app,lightbar,app.get("item"+item));
+		else {
+		    var target = app.get("item"+item);
+			var an = new animate.linear(app,lightbar,target[5],0.3);
+		    an.start();
+		}
 	} else if (evt.keycode == mbapp.KEY_DOWN) {
 	    item = item + 1;
 		if (item == 10) {
 		    item = 9;
-		} else
-            animated_start(app,lightbar,app.get("item"+item));
+		} else {
+		    var target = app.get("item"+item);
+			var an = new animate.linear(app,lightbar,target[5],0.3);
+		    an.start();
+		}
 	}
 });
 app.loop();