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Can anyone help with some kind of grass deformation flowmap solution?

Hi, I was wondering if its possible to create some kind of custom map that you can plug into a grass shader, so you can paint deformation onto it (bonus points for being able to paint interactively in engine)?

One thing about grass that no one has seemed to try to replicate yet, is being able to paint in “mowing” lines that lawn mowers leave behind - I’m trying to replicate this effect but the only solution I can think of is disabling foliage rotation and bending the meshes up/down in a 3D program, but it’s not the most elegant solution.

I assume this can be done within the material, in a similar way to characters pushing grass aside when they move through it?

Been there, done that.
Its a time hog/expensive but it runs nice and smooth.
At some point in the next 4 months or so it might make it to a new release of DynoFoliage.

The vectorfiled shader distorting with a time sine

Moving the vectorfield across the meshes

Using the vectorfiled for local displacement (trails).

Also, mowed grass is really not a good candidate for it. To do that you are far better off just using the same method as carpet with a parallax shader.

And like with anything else, you could paint whatever into it at runtime via a render target.

Why is it not a good idea to acrually bend the grass?
Because of the sheer amount of meshes you need for grass to look half decent.
Even with an optimized material and the effect correctly applied on ALL lod(s), for a decent look you need billion of tris… when a parallax map needs next to nothing.