Niagara: Get TriUV

What exactly am I getting with this node and how do I use it?

I see a tutorial where the guy used the TriUV’s off the mesh and then piped that into a DynamicParameter and HIS particles are showing the right part of the material on them when they’re spawned on the mesh.

However, what he’s doing is taking the A and B inputs of the DynParam and simply using a CreateVector2D and plugging that directly into the texture’s UV’s.

When I do that, my particles get filled entirely with a single color. It seems to be the color of the middle of the TriCoord, but clearly the UV’s have the wrong scale…like the scale feels like 0.

Try plugging a V2 into the UVs of any texture…it just goes flat color.

So, how do I spawn particles on the random surface of the mesh and actually get the UVs from that information to be piped into MY material so that my particles show the correct part of the material based on where they spawned on the mesh?

I have tried appending the DynParam and adding/multiplying/dividing…etc a UV node like I normally do to control tiling and position. UV nodes aren’t just freakin V2’s right? There’s more. They have size and position…plus the UV Coordinate Index. How is it that plugging a simple V2 in this guy’s tutorial works for him at all? It doesn’t make sense.

Thanks for any help.

Here’s the tutorial:

at 7:45, he hooks up the part that has never worked for me.

NOTE: I have no issues getting the UVs to properly adjust when I use the Grid Placement and the normalized Grid UV’s. While I have to scale the UVs manually to match my grid layout, they do take on the right coordinates and it’s done by simply appending the parameters together and adding it to the UV node…like I’ve ALWAYS done. The scale is handled by Params 3&4 and it’s the UV node divided by that. I pipe the Grid.Size from Niagara into those two spots in the Module Spawn script.

What’s irking me here is…I simply cannot tell wtf GetTriUV is even giving me. I know I need to incorporate the legit UV node in the material so that it’s treated as…well…UV Coordinates…and not just a v2 like 1,1 So since I have no idea what even range the values I’m going to get are or how they’ll correspond to literally anything stops me from knowing what math to run on them in the material to translate that value into the correct 2 values I need to correctly display the material.

Ok, that’s 3 ways of explaining. I will put up a video in a week if that’s not enough to make the question clear.

How do I do the material part of sampling a staticmesh in Niagara so I can build it out of particles?

same issue - did you fix it?