Changing to left-handed system?

Troubleshooting graphics
1

Hello again Jmonkeys,
I’m working on an editor for a game which follows the left-hand rule for axis orientation (X starts from left and goes to right, Y starts from top and goes to bottom, Z starts from far and goes outside the screen).

but JMonkeyEngine is right handed, so I really have to change it. I didn’t find any answer on internet about that and I really need your help :slight_smile:

Thanks,
Axel

2

We can’t say how you can change your system to serve a right-handed coordinate system as we don’t know it. OpenGL is right-handed so you will have to deal with that.

3

Well the most simple way is to twist your user interface.

Eg when entering a position translate it to jmes corrdiante system.

4
@Empire Phoenix said: Well the most simple way is to twist your user interface.

Eg when entering a position translate it to jmes corrdiante system.

With translations is easy enough, but what about the rotations? My quaternions follow the right hand…

5

Well you can guess how this works then or?
Basically you need to do the same, but in 4d with 2 imaginary numbers projected onto a 3d space ^^.

Or if enough, convert to angles, transform those convert back.

6

So you’re second suggestion is:

  • take the euler angles give by the user
  • transform into a quaternion
  • before rendering converting them again in eulers and making them the opposites

It could work, but as I need to do animations (i.e. SLERPs), would it work anyway? I mean, should i do this process after everytime I perform a slerp?

7

Whyn not before, and calculate the slerp stuff in the jme coordinates then?

8

You’re right. I don’t like this type of workaround, but it seems to work as expected. I will post the result with the slerps :slight_smile: