what's the best way to get an actor to follow a bezier curve?

Any one got a simple way to get  an actor to follow a bezier curve from a list of point?

I've played around with Actuate.motionPath but with no luck - I've looked at other peoples suggestions, but my app doesn't compile, and I get an  "Type not found : MotionPath" error

http://community.stencyl.com/index.php?topic=42775.0

Hi greatanthony, i'd seen that post, but am not sure how to implement it. Were does the public function go?

hi,
if all the code logic is understood and only public function is the problem then it should not be hard...

Public function was throwing error b'cause the code is already added to a Event ( or a public function )....

In any event Add the [Code ] block and add the code below to it...

Code: [Select]

tweenLoc.x = getX(false);
tweenLoc.y = getY(false);

if(easing == null)
{
easing = Linear.easeNone;
}

activePositionTweens++;
var path = new MotionPath().bezier(x, y, checkPointX, checkPointY ,strength);
Actuate.motionPath(tweenLoc, duration, { x:path.x, y:path.y }, false ).ease(easing).onComplete(onTweenPositionComplete);

Put own number inputs in input place like (x , y , strength)  in the code...
Am typing on mobile, sorry for any typo, let know about progress.....

Anthony

Add a custom import in your actor behavior and add this into it:

Code: [Select]

import motion.MotionPath;

After that add the following code in a different event (like a click event or something that's not the Always or Draw event)

Code: [Select]

var path = new MotionPath().bezier (100, 100, 50, 50);
Actuate.motionPath (actor, 2, { x: path.x, y: path.y });

That will make your actor move from it's current position to 100,100 using 50,50 as control points. You can replace those numbers to match your curve points.
The 2 in the second line is the time that the actor will take to reach the target you want.
You can even add a strength to the motion path to tweak how strict the player follows that path should you need to.

works great!! 

Thanks SadiQ, the import motion.MotionPath; was the bit i'd missed.

@SadiQ, there is an important inconvenience when using your code: while the actor is moving, and even when the tween has finished, the actor coordinates are not updated.

Do you know how to solve this? Please.

I did a quick test before I leave the house. It seems the collision box doesn't move with the actor(I'll test more when I get back home).
In the mean time you can try this:

Code: [Select]

var path = new MotionPath().bezier (100, 300, 50, 50);
for(actorOfType in getActorsOfType(getActorType(8))) //my test actor
{
if (actorOfType != null && !actorOfType.dead && !actorOfType.recycled) {
var obj = { X:actorOfType.x, Y:actorOfType.y };
Actuate.motionPath(obj, 2, { X:path.x, Y:path.y }, true ).onUpdate(function() { actorOfType.setX(obj.X); actorOfType.setY(obj.Y); } );
}
}


Now, your new code causes this error:

Events for 'Scene': For expression should be 'v in expr'
   from scripts.SceneEvents_0
   line: 123
   columns: 4-11

Then, if I remove the "for(......)" line, the tween works incorrectly, causing these two issues:

- The actor position is suddenly changed just before it starts moving. (half of its width and half of its height)
- Also, strangely, I get the #1009 error if I reload the scene while the tween is running:

Code: [Select]

TypeError: Error #1009: No se puede acceder a una propiedad o a un método de una referencia a un objeto nulo.
at com.stencyl.models::Actor/setX()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/stencyl/1,00/com/stencyl/models/Actor.hx:2556]
at MethodInfo-6344()[Source/scripts/SceneEvents_0.hx:127]
at Function/http://adobe.com/AS3/2006/builtin::apply()
at Function/<anonymous>()
at motion.actuators::GenericActuator/change()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/actuate/1,8,6/motion/actuators/GenericActuator.hx:140]
at motion.actuators::MotionPathActuator/update()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/actuate/1,8,6/motion/actuators/MotionPathActuator.hx:225]
at motion.actuators::SimpleActuator$/stage_onEnterFrame()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/actuate/1,8,6/motion/actuators/SimpleActuator.hx:579]
at com.stencyl::Engine/update()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/stencyl/1,00/com/stencyl/Engine.hx:2324]
at com.stencyl::Engine/postUpdate()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/stencyl/1,00/com/stencyl/Engine.hx:2619]
at com.stencyl::Engine/onUpdate()[C:/Program Files (x86)/Stencyl_v34_B9328/plaf/haxe/lib/stencyl/1,00/com/stencyl/Engine.hx:2595]
Sorry, I don't have much idea about Haxe code, so I hope you can solve these issues.

Can you post the code you're using?

The actor is previously stored in the attribute called TARGET
   


I removed the "for(_TARGET)" code line to avoid the "For expression should be 'v in expr'" error message.

   

I'll have to call it quits on this one for now. I tested things all afternoon yesterday without any results
It seems the .onUpdate(function() { actorOfType.setX(obj.X); actorOfType.setY(obj.Y); } ) part doesn't get cancelled when the scene changes and I haven't found a way to work around the issue (and no ...checking if the scene is transitioning doesn't solve the issue).
If someone else can test this I'd learn something new from this problem.

You have to inspire yourself of Stencyl, which has already solved the case for you
They're using an attribute tweenLoc to take care of our problems
https://github.com/Stencyl/stencyl-engine/blob/0e67a519288eefdd6eaddb4f0989db7fab026932/com/stencyl/models/Actor.hx#L3589

Solution

Replace _actor by your actor
you can change the ease ( stron ing, bounce in these kind of things) look at the code of a block using the ease to find the name you want

Code: [Select]

_actor.activePositionTweens++;
_actor.tweenLoc.x = _actor.getX(false);
_actor.tweenLoc.y = _actor.getY(false);
var path = new MotionPath().bezier (100, 300, 50, 50);
Actuate.motionPath (_actor.tweenLoc, 10, { x: path.x, y: path.y }).onComplete(_actor.onTweenPositionComplete).ease(Quad.easeInOut);

Reloading and collisions work

Dooh....I tried that one but failed to initialize tweenLoc like you did, so my test failed.
 I knew it was some silly mistake of mine