Help Making Foliage
polycounter lvl 17
Hi there,
Any good resources out there for making foliage? Happy to look at any good tutorials out there.
I'm starting with a Fir tree. Started with a pine needle and working up from there.
I understand about bent normals, more interested on how to construct the low poly mesh.
Just want to make something nice.
Replies
Try to match the leaf cards shape closely to the basic shape of hi poly leaf mesh. This will reduce overdraw. More triangles won't kill you. The leaf card for that hi-poly mesh could look more like a diamond with a thin tail.
Have a straight edge that goes down the length so you can fold the card slightly downwards. A few edges perpendicular down the length allows you to make a few variations for drooping leaves, perky leaves, and so on.
Each card doesn't have to be a single leaf. One card can be more like a large branch system. It really depends on the level of fidelity you need balanced with performance considerations.
You can use small individual cards for up close details (like on lower branches camera might see) and use bigger fillers for up higher, or jsut to fill in thicker areas.
Looks to me like modern games are using trees with up to 30k triangles for individual tree at the lowest LOD. In my game I am using trees with around 10-15k tri's per tree, but it doesn't look as nice as say, the latest Ubisoft games.
Making trees is not unlike character art, or any art really. Start with the big shapes and go down from there. Focus on form, color, etc, and don't have nose in the details of individual leaves until all the big problems are solved first. To be honest, there is so much high quality scanned stuff out there available for free or cheap, I wouldnt bother constructing leaf card textures from scratch unless I just wanted to as an exercise, or needed something stylized.
A great exmaple you can get for free is the Rural Australia pack on epic marketplace. That's a good balance between fidelity and performance. When you get to rendering that will be helpful.
Thanks for the comments
Can someone explain why and how distance fields are used for foliage textures?
Where did you hear that? A bit more context will help. Distance fields are useful to blend meshes into terrains, so you could perhaps use it to blend a tree trunk with the ground.
2d distance fields, not 3d
You use them in the alpha channel with clip/alpha-test materials.
The use case is that you reduce the clipped alpha value as view distance increases which mitigates against fine detail being destroyed by mipping.
Pretty sure guerrilla have a write up on it somewhere online.
Yeah, that sounds like it. Thanks for the description.