Volume Render Target to give location to spawn particules

Hi

I am trying to use a volume render target to spawn additionnal particules based on the G channel of that volume render target texture but I can’t get anywhere with it. Is there a possibility that I have to do something special with the UVs ? I only have access to U and V but not W unfortunately.

I have the ImportLocation variable that spawns a particule but the goal is tu supplement it with a position comming from the 3D texture in the Sample Texture node.

Here are images of my setup. Thanks a lot !