Can you hide certain parts of an actor?

Development Programming & Scripting
1

I’m making a board game and there’s a flat “particle system actor” that spawns on my board. It works fine but when it is on the edges of the board, it extends past it. can I somehow crop it or hide the extra parts?

I was thinking about putting up a collider or something like that to hide it when they’re overlapping…
Do we have such thing in UE4?

2

hey there.
you can use a collision volume, and use the collision event of your particle system or even use the kill box event :

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3

Or if you’re using Niagara:

314142-killvolume.png
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  1. Add a Kill Particles in Volume module in Particle Update section;
  2. Set box as shape and set the required dimensions;
  3. Invert volume, so the particles would be killed once they are outside;
  4. Create a vector user variable and bind the Volume Origin to it; with it, you can align the kill volume with the board.
4

I appreciate the reply but this doesn’t work for me. My particle system consists of only one big particle.
If I try to kill it out of the bounds, the whole thing will get deleted:

314187-screenshot-2020-09-18-200232.jpg

Any other ideas?

5

you can do that in the material itself.
there s a node called box mask 3d.
u give to that box the same position and dimension of your board, but with a wider height, and use that box to mask your material.so it will appear on the board but not outside.

6

wanted to ask the same thing :slight_smile:

7

Then a box mask is a way to go, as suggested by expose.

One question though: if it’s just one large particle, can’t you do the same with a decal (or a plane if it’s not on the surface)? Or is it supposed to be affected by some forces in a particle system?

8

Thank you so much. that’s exactly what I’ve been looking for…

And about your question, yes I could use a decal instead but its not just a stationary image, so It was easier to use particle system options instead of writing a material function from scratch.

9

your welcome. mark the question as answered for archival .
good luck.