AI - Pawn movement component Issues

Development Programming & Scripting AI
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1

Hi,

when ordering the pawn (with a floating pawn component) to move to an Actor the following issues appear:

  • The Actor and Pawn Movement component velocity grows larger and larger the more distant the target is
  • Deceleration and acceleration doesn’t seem to have any effect
2

Hey AlexW88,

  • Could you provide a bit more information about your setup?
  • Do you have screenshots of your blueprints?
3

Sure, but its really Simple.

96830-ai.png
96830-ai.png1500×796 290 KB

So I order the AI to move to Actor, it will then go to that Actor with the Set speed. However, the Velocity printed in the Anim BP is much larger than the actuall speed. If the AI is really close to the Target, the velocity is about 2000. If the AI is about 5 meters away from the Target, the Velocity is about 10.000.

And no mater what I set for Acceleration or Deceleration, the move speed nearly instantly go to max speed.

4

Hey AlexW88,

After investigating this issue, it appears that acceleration and deceleration are currently not supported for path following. This would explain why you’re not seeing the desired results in your project. There is a feature request in for this to be implemented, UE-17495.

Let me know if you have any further issues related to this.

Have a great day

5

Thank you.

So the incorrect velocity is a result of the lack of deceleration? May I ask you to bump the importance of this Request? Is there a chance that this will make it into the engine within the next few months?

tbh. this is a real bummer, I spent countless hours to find an efficient AI solution allowing me to run several k at once. Without knowing the real velocity it would require alot of unnecessary extra calculation to get a reliable system

6

To me, that definitely sounds like the source of the issue.

I have increased the community interest on the report; however, this does not guarantee that the feature will be implemented. We are currently focusing our engine efforts on high-priority crash and showstopper bugs, and as a result features have received a lower priority. Also, keep in mind that if you decide to implement a feature yourself, such as what you are looking for in this case, you can always enter a pull request to be considered by our developers.

Let me know if you have any other questions regarding this issue.

7

So according to Unreal Engine Issues and Bug Tracker (UE-17495) this Issue has been fixed, however the problem I described above still persists.

Following the Developer note by checking “Use Acceleration for Paths” just prevents the AI from moving at all, which seem to be another bug FloatingPawnMovement "Use acceleration for paths" not working? - Blueprint - Epic Developer Community Forums

8

Interesting, I’m not seeing the same issue in my test project. Would you mind providing a repro case so I can take a closer look? A detailed list of steps or a test project would be sufficient since I’m not experiencing the same behavior. We probably have slightly different setups.

9

Open the “Level” level and hit play.

  • AI X will print incorrect velocity
    from the animation Blueprint
  • AI Y won’t move as long as “Use
    Acceleration for Paths” is checked

link text

10

I was able to reproduce the issue in a clean project based on the project you’ve provided, and I have entered a bug report which you can track using the link below:

Have a great day

11

May I ask why this was flagged as can’t reproduce?

Also in regards to the original Issue I think it may be independant from UE-43261.
When reading the Velocity inside the Pawn Blueprints, it returns the correct veloctiy, reading the same value (see example project) inside the Animationgraph it prints the distance to the target instead the velocity.

If you open the ai_test project attached above and play the level you will see that the AnimBP of AI_X prints a complete different velocity then the AI_X, which actually prints the correct veloctiy - both using the same nodes!

12

This issue no longer reproduces in our main internal branch, which is why it was marked as cannot reproduce.

After the release of 4.16, if you’re still experiencing the same issue, feel free to leave a comment to reopen this thread to let me know it’s still occurring and I’ll be glad to continue to investigate.

Thanks

13

4.17.1 issue sill reproduces for AI path following (AI MOVE TO)
Incorrect velocity and not respecting acceleration/deceleration.

14

Hey Jake1337,

Is the movement actually being disabled? The ticket that was related to this issue was specifically that “Use Acceleration for Paths” would completely disable pathfinding. If you think you may be running into something different, please open a new thread in the Bug Reports section and provide as much information about the issue as possible, including a detailed list of repro steps or a test project that we can use to see the issue on our end.

Thanks