Grass Object >>> multiple meshes for intersection

[werner.poetzelberger]

I am putting a grassobject on top of multiple meshes.

How can I activate all meshes for intersection with the grass >> so that the grass grows on the surfaces of all meshes?

Thx.

Werer

[silent]

Hi Werner,

AFAIK grass can only interact with a single mesh only (if we are talking about grass mesh mask), so the best option would be to merge all your separate meshes where grass should grow into a single mesh.

Thanks!

[werner.poetzelberger]

Hmm. I am building a ground surface using many different meshes, imaging a lot of different ground objects to form the landscape. I want to grow the grass on top of all of them.

I cant imagine to merge all of those objects.

How would I achieve that? probably I need to copy the grass object and place them under every mesh object to grow on (in the hirarchy)?

best.

Werner

[silent]

Multiple grass objects will reduce performance, so it's not recommended to go with this approach.

You can try select multiple meshes inside Editor and export them into a single .mesh file. Or prepare this mesh in 3rd party DCC tool and import as mesh mask for grass. That should do the trick.

[werner.poetzelberger]

Okay. Will try that.
Btw I not using a mesh mask!!
I just want the grass to grow on the object (as a collision object when generating the grass position >> the grass sits on that surfaces).

Then I use image based masks for the areas where the grass is actually growing.

But I need the grass to sit on top of those surfaces.

Edited March 13, 2023 by werner.poetzelberger

[silent]

OK, now I got what you want to achieve :) You can ignore mesh mask option.

However, you would need to combine this ground surfaces to a single mesh anyways, since Object Grass can intersect with only a single object at once (with a single parent node - either terrain or mesh).

Or you can try to use a separate grass object for each mesh (possible performance issues).