Hello,

I made a simple advection of particles through a vector field. Im rather happy with the look of the field, the issue is the actual velocity. The way the field was set up, the velocity is very low at the center and increases towards the edges. Since My particles are spawning in the center, this causes them to have no velocity at all!

Is there a way to remap the speed while retaining the direction and look of the vector field? Even just inverting the speed from the center to the edges would solve my issue.

Any suggestions are welcome! I attached the hip file in case you need more info.

Any ideas? Someone earlier answered to simply up the velocity scale in the pop network but this just leads to weird particle behaviour, not what I want.

I guess this issue is more complicated then I thought. I assumed its a simple problem at first!

Hi, you have to normalize both vectors before cross product vop, and then try normalizing after trigonometric function vop.

Could try adding a pop speed limit, with the min and max speed set to the same value.

vicvvsh
Hi, you have to normalize both vectors before cross product vop, and then try normalizing after trigonometric function vop.

Thank you vicvvsh, normalizing before the cross product worked quite well, I didnt know about this!

mestela
Could try adding a pop speed limit, with the min and max speed set to the same value.

Wow that is cool, I dont know exactly what is going on since Im rather new to houdini but I will study this file. Thank you Matt, and I love your cgwiki site, it helps my learning a lot!