AddWorldRotation inaccuracy problem

Development Programming & Scripting Blueprint
1

Hello,

I am trying to align two actors A and B by adding the difference of the rotation of A and B to the rotation of A - just like you could make it to align it’s locations (A.location = A.location + (B.location - A.location). Don’t ask why I am doing it this way and why I not simply set the rotation of A to the rotation of B - I need to do it this way for another function. It should work, anyway.

inaccuracy.jpg
inaccuracy.jpg1031×473 116 KB

When calling the function “New Function 0” (in the level blueprint) with the location this works without any problems. If I am doing the same with the rotation this happens:

inaccuracy2.jpg

It’s inaccurate! The rotation of both cubes is not the same. If I call “New Function 0” again (2 times at all), it’s slightly more accurate:

inaccuracy3.jpg

After three calls:

inaccuracy4.jpg

After four calls it looks good. Both cubes have almost the same rotation:

inaccuracy5.jpg

I think it’s clear that this has something to do with inaccuracy. I need to call the same function 4 times to get a good result.
How to deal with this? What is the problem? How to make it better so that I don’t need 4 calls?

Thank you,

Thilo

2

Use *AddRelativeRotation *instead of AddWorldRotation.

3

For some reason this works. Thank you.

But for some other reason, this does not work:

rot.jpg
rot.jpg1056×543 134 KB
I am trying to align two scene components on their sockets, so that at the end both sockets have the same rotation and the same location. So I thought this would work:

  • Move Component 2 for the difference of the socket locations of Component 2 and 1 -> both sockets have the same location
  • Rotate Component 2 for the difference of the socket rotations of Component 2 and 1 around the socket of Component 2 -> both sockets **should **have the same rotation

There are cases of rotations of Socket 1 and Socket 2 where:

  • this works
  • this does not work, but it works with (5-10) iterations of this function
  • even with infinity iterations it does not work

I don’t understand why this isn’t working…

4

Try this one:

2.jpg
2.jpg1579×598 218 KB

5

Thanks. Unfortunately this doesn’t work if

setup of the first socket:

socket1.jpg
And of the second socket:

socket2.jpg
While using Shape_Cube for both static meshes.

6

Can you show a pic of how the cubes are supposed to look like in that example?

7

I think you got it already. There is something strange going on with the rotations. Maybe it has something to do with the order of Euler rotations…

I found an easier example.

This is socket 1 on cube 1:

sock1.jpg
sock1.jpg1280×1024 236 KB
This is socket 2 on cube 2:

sock2.jpg
sock2.jpg1280×1024 229 KB
Before calling the function they look in the world like this (I added debug coordinate systems with the socket’s transforms):

sock3.jpg
After the function (e.g. yours like above) they look like this (socket coordinate systems not fully aligned):

sock5.jpg
But they SHOULD look like this (looks like one coordinate system, because both socket’s coordinate systems have exactly the same origin and rotation):

sock6.jpg
It makes me crazy that I can’t get this to work :wink:

8

I really don’t know, why, but this seems to work:

  1. Rotate the scene component 2 to that it’s socket rotation is (0,0,0)
  2. Rotate the scene component 2 to the rotation of the socket rotation of scene component 1

socketsx.jpg
socketsx.jpg1025×389 86 KB

9

Just test it and it works. Nice.