I try to cretea a sphere/hemisphere emitter in PG which one its start point from center and the particles are outdiffusion.
here’s the png and PG:
I copy the same code to create the same sphere/hemisphere in my project and get different result.
Two start point in two side, particles indiffusion.
I had test V5.4, V5.6, V5.7, V5.8,V5.9, V5.10, V5.11, and got the same strange direcion.
Need help, please
Could you provide a playground of your none working version ?
The hemispheric one seems to be ok as well here: https://playground.babylonjs.com/#MRRGXL#481
Check this PG, setting emitter = ‘sub mesh’ of model, then all particles to be indiffusion
This is expected as the rootNode as a rotation of 180 degrees so reversing the flow of particles in your case you could attach to rootNode.absolutePosition ?
may I just add the negativ Z scaling does also not help 
That should solve the problem, shouldn’t it?
Attach to position isn’t i wanna be, because ps couldn’t follow the mesh moving
What Sebavan is explaining here is that the root node of your mesh (probably an import from Blender) has been rotate and inverted along the z axis to conform with the left handed system of BJS.
However, using this as an emitter will keep with this value of 180° on Y rotation and -Z on scaling to set the origin and direction of your particles.
For whatever method you choose, if you don’t want inverted particles from your source/origin, you need to have it at zero. Else, your particles will be starting from 180° on Y and will move towards the inside due to -Z (instead of Z).
ok, the right handed system work well, i have to someting inverse
