VFX Graph. How to spawn patricle with a mask image

Greetings everyone,
i go straight top the point: i am new to the VFX graph but i need to use it to obtain a effect like the "Simple Swarm Patricle System" but with a difference... i want to spawn modify the patricle density with the shape of a mask (think of a perlin noise) that i generate within Unity.
Maybe this is simple to archieve but my lack of experience with this tool make things harder.
I try to study the Voxelized Map of the Unity Examples but still i cant figure out how to use the nodes to obtain what i want.
I only need the particle to spawn OR modify the patricle density within a XY value based on a map.
Thanks in advance!

 

hey, did u find a way to do this? got the same issue...