I have been asked by a client to create a rendering of their turf in a football field setting. Trying to do this in cinema 4d with the hair module is not usable due to how much hair I have to generate to create all the grass. So my next thought was unreal… even though I have almost no experience with it. So, I’m wondering if anyone know if this is possible to do in unreal - create grass and apply a texture to it to drive the color of it - and if so, how? Thank you!
Look up tutorials on YouTube. There are tonnes of them on grass.
If your grass is synthetic you won’t need much at all.
At a high level you need the model of the pattern of the grass, with that you generate a single line of geometry, you create a strip that contains the geometry and you bake the geometry to the strip to obtain the different textures.
You then generate a static mesh - for astroturf its quite low/pointless btw - and use the engine Grass output on the material to create a grass instance.
Theres exact tutorial on that procedure within the docs - procedural grass is what you want.
If your light is static and the color of the grass matches the color of the floor texture exactly you won’t have issues and can probably get by with less tris on screen for you would really struggle to notice blades of fake plastic grass further then 10m from the player…
Yeah I’ve looked at quite a bit of grass tutorials but can’t find ones that actually discuss coloring the grass with a texture like what I’m thinking I need to do.
Sorry I’m not following your how-to description very well. “you need the model of the pattern of the grass…” do you mean I need the texture that will be applied to the grass or I need to model the plane and all of the grass blades? And is this all in unreal or starting in c4d?
Starting in cad you have to create the base geometry of the blade of grass.
or in your case with the fake astroturf, the single clump that resembles or is the exact same as the one that actually gets 3d printed.
you then need to line them up, like they would be in a section of the material.
After that (not sure if in cad or taking it elsewhwre) you need to convert it from actual 3d geometry to a flat plane for positioning.
In blender you can somewhat easily bake the textures down onto an angled plane. - make sure it is angled, so it is visible from both the top and from the front.
Once you have the single plane with the textures you can expand it and make the single plane into several ones.
Astroturf is uniform, so you just need a way to go from the 300 to 1000 tris of the complex mesh to something reasonable - around 150 to 200 tris is good - of the base mesh.
After that, it’s simple enough. You import the file into unreal, create the material, and assign the procedural grass mesh as even the docs tell you to do.
play with the settings for distribution and all of that.
Now for the lines on the floor you can actually easily play with the Grass output.
Just create another one, call it white grass, and you can then easily paint it on the terrain at will. In any shape.
the different grass mesh with the different material will be added to the terrain - just by using the regular layer nodes. Nothing special is needed really.
The material instance for the mesh can just have a modified albedo, and you are good to go.
I would however suggest you figure out a way to use a texture to bring in the patter of the painted lines.
With the new landscape blueprint tools and additive layers this shouldn’t be hard to do.
At a high level, take the texture make it black/white and subtract it from the grass to get no grass output on the white line.
add it to the white grass to get those lines to always output regardless of the painted layer.
Hope that helps a little more.