Moving object along a path from point A to B [3.8]

Cocos Creator
#1

Hi all.
This is my first post in Cocos community.
I am working seriously on developing a 2d game using Cocos creator 3.8.
I want to know how to move a node from point A to B (of course A and B positions are not fixed.)
I don’t want to to movement to be on a straight line. It should follow a predefined or programmatically specified path.
The movement can be in any direction. I found the action system in older versions was suitable for my purpose like described here but I can’t locate it nor it’s equivalent system in 3.8.
How am I supposed to do my task in 3.8

#2

After 3 days of search and just when I posted my topic, I finally found Tween system.
Is this it?

#3

You can make a simple way point system that contains my points. Then move object toward each point. There are plenty of ways to do that. Vec3.moveTowards for example.

Tween is also a a way. If you want a curve movement, check out bezier path.

#4

Thanks for answering.
Vec3.moveTowards seems a bit wild to me!!!
Why not exactly specify the point with specified distance? it seems non-deterministic. unless the documentation wants to say this:
Calculates a new position from current to target with maxStep distance, unless the distance to target is smaller than maxStep.

I implemented my solution using tween, like this:
lets say i want my forces to march on a path.
first I considered an empty node as parent(called them “march plain”) of my forces which are generated using a prefab.
The prefab contains an Empty node(called “unit”) and a sprite (called “body”) as a child
Then I gave the unit a script that has a function that receives a mission containing start and end point
now a mission is carried on as follows:

  1. instantiate and rotate the march plain to align the march path.
  2. instantiate the unit and set its parent to march plain
  3. in mission function I calculate the distance and move the unit in update function along the x axis with calculated distance regarding the specified move speed.
  4. used a tween on body to animate the y position of body.

I’m almost happy with the result, But I don’t understand what you mean by Bezier path. Can you provide a link to a class or documentation

#5

https://docs.cocos.com/creator/manual/en/ui-system/components/editor/graphics/bezierCurveTo.html

This is bezier curve. It means to make object move in a curve path.
You can also make object move in a curve path with tween using custom easing function.

Vec3.moveTowards is really straight forward to use. It will move an object towards another object, with maxStep equals by speed * delta time. So you move the same distance every frame.
Then you only need to check if your current object is within a small distant from destination. if it is within range, you arrive at the destination.

also you could use a “lookAt” to rotate your object towards the target direction.

finally, if you want to make an enemy unit that patrols between check points, and if the unit uses physics, i strongly recommend to check out movement with rigidbody.

#6

nice pieces of information.
Thanks.

About those curves in graphics component. How are they used for movement purpose?
Actually I was aware of them but did not think you were pointing to this.
Aren’t they just for drawing purpose?