[Getting a train with multiple waggons to move along a bezier path]

For whom it may concern...
I came up with an ugly but effective hack as a solution:
 

private const MAXDIST:Number=44;

//and at the end of the buildTimelines function
var car0:Sprite=_train.cars[0]
var car1:Sprite=_train.cars[1] 
//
var delay:Number=0
while (dist(car0.x, car1.x,  car0.y, car1.y)<MAXDIST){
	
	for (i = 0 ; i< _timelines.length; i++){
		delay+=0.00001
	   	var tl=_timelines[i]
	   	tl.progress(1-delay*i).timeScale(0);
		tl.pause();
	}

};
// just a little distance check
function DistanceTwoPoints(x1:Number, x2:Number,  y1:Number, y2:Number):
	    Number {
	    var dx:Number = x1-x2;
	    var dy:Number = y1-y2;
	    return Math.sqrt(dx * dx + dy * dy);
}

[Getting a train with multiple waggons to move along a bezier path]

hmm, damn, than it will be more work than i thought ... 

[Getting a train with multiple waggons to move along a bezier path]

hmm, is there anyway TweenMax / TimeLineMax gives me the length of the path?

 

i only found duration() totalDuration() as a time value.

[Getting a train with multiple waggons to move along a bezier path]

Hello Carl, 

 

thanks for your time.

Unfortunately though, this is still not the answer.

When changing the length of the track, the distance between the "wagons" still changes.

with the Value 0.15 and the length of this demo "track" it is barely noticable.

however when you change the values to something a higher it is there.

 

hmm 

[Getting a train with multiple waggons to move along a bezier path]

Just a tiny polite bump

[Getting a train with multiple waggons to move along a bezier path]

hi guys,

i hacked together a new version with external assets.

will work now also with older flash versions.

 

you just need to define the DocumentClass as TrainDemo and add the greensock classes.

 

cheers!

TrainDemo.zip

[Getting a train with multiple waggons to move along a bezier path]

hmm, ok, maybe i produce a version which works with ye olde flash 5

[Getting a train with multiple waggons to move along a bezier path]

hello and thanks!

 

 

 

Is there a reason you don't have the wagons using the same length path as suggested by Carl?

well the reason for doing so, is that i want the train to have the same speed no matter what the length of the track is.

to do this i introduced the SPEEDPERTILE multiplier. this way the speed stays constant no matter how long the track is.

i hacked up a little simplified example with fixed path values. ( in my original, the tracks get created dynamically and always a little different.

you can click on the switch to see the difference. 
Thanks!

 

 

[Getting a train with multiple waggons to move along a bezier path]

hi carl,

 

no each track is different in its lengths.

this is why i used the SPEEDPERTILE multiplier and then used the progress/delay per car as a relativ value based on percentage.

[Getting a train with multiple waggons to move along a bezier path]

Hello Carl,

 

sorry, here is some more code (simplified for the example):
 

private const SPEEDPERTILE:Number=.2
private const NUMCARS:Number=3

// this gets computed at runtime by the trackparts the player used.
private var _path_values:Array

_speed=_path_values.length*SPEEDPERTILE;

for (var i:int = 0 ; i< NUMCARS; i++){
	var tl = new TimelineMax({repeat:1});
	tl.add(getTrainPartAnimation(i));	
	tl.progress(1-DELAY*i).timeScale(0);
	tl.pause();

}

private function getTrainPartAnimation(i:int):TweenMax {

	var car:Sprite=_train["train_"+i];
	
	TweenLite.set(car, {x:_path_values[0].x,y:_path_values[0].y});
 	var tween:TweenMax = new TweenMax(element, _speed, {
   		bezier:{
     		type:"soft", 
     		values:_path_values,
     		autoRotate:true
   			},
   		ease:Linear.easeNone
		}
		
		);
	
	return tween;
}

the time() method gives me the same issue ...

hmmm

[Getting a train with multiple waggons to move along a bezier path]

hmm, one more thing:

 

in order to create the illusion of the "waggons" following each other, i used
 

tl.progress(1-delay*i).timeScale(0);

where delay is a factor from 

tl.totalDuration() / DELAY *100

and DELAY a constant.
the "speed" or length of the timeline depends on the number of trackparts in oder to keep the animationspeed constant no matter how long the track is.

unfortunately with this method i do not get consistent delays between the "waggons" 
 

any idea where my mistake might be?

 

thanks!

[Getting a train with multiple waggons to move along a bezier path]

Hello Carl,

 

i did it now with multiple timelines.

it works pretty good.

dont know about the performance hit though ...

[Getting a train with multiple waggons to move along a bezier path]

hi carl,

i played around with your code.

problem is: if you see the begin and endpoints of the "track" the illusion does not work anymore.

in my case you see a closed track including the beginning and end ...

hmm
 

[Getting a train with multiple waggons to move along a bezier path]

thanks a lot carl,

 

i will look into that.

[Getting a train with multiple waggons to move along a bezier path]

Hello Folks,

 

i am trying to build a little educational application in which i need a train to follow a dynamically created bezier path.

i have alredy built the whole thing using TweenMax and the Bezierplugin. 

TweenMax.to(train, SPEED, {bezier:{type:"soft", values:path_values, autoRotate:["x","y","rotation",0,false]}, ease:Linear.easeNone});

however i would like the train to consist of at least 3 to 5 separate parts, which should move like a real train on the tracks.

 

at the moment my brain seems to be blocked, so i do not know how to do this using the TweenMax/Lite Tools.

for example how can i make the second "waggon" follow the first one?
 

Thanks for all tips!