Grass in Rocket Arena (or other sports games)
polycounter lvl 20
I was wondering if anyone has insight in to how the team at Psyonix made the grass for Rocket League?
It looks like some kind of shader that is generating the geometry of the grass rather than a simple grass mesh/actor that's been painted with the vegetation tool in Unreal.
In the above two samples you can see how its being masked/blended in to non-grass materials (like dirt/bud).
The bottom left image shows that the shader adopts the colours on the field itself (in this case orange and green).
The bottom right image is just an example of even distribution of the grass asset.
What I am mostly interested in is how a shader is made that will populate its surface with geometry in addition to shader definitions, inside of Unreal Engine 4. Unless I am mistaken in how they've done it.
From there I can figure out colour adoption and masking/blending.
It looks like some kind of shader that is generating the geometry of the grass rather than a simple grass mesh/actor that's been painted with the vegetation tool in Unreal.
In the above two samples you can see how its being masked/blended in to non-grass materials (like dirt/bud).
The bottom left image shows that the shader adopts the colours on the field itself (in this case orange and green).
The bottom right image is just an example of even distribution of the grass asset.
What I am mostly interested in is how a shader is made that will populate its surface with geometry in addition to shader definitions, inside of Unreal Engine 4. Unless I am mistaken in how they've done it.
From there I can figure out colour adoption and masking/blending.
Replies
https://www.youtube.com/watch?v=Yq7vacDrJgw
If you make the material slightly more complex you can set the scale of the scatter objects to be driven by the layer mask. So a grass clump that lands on a 50/50 blend gets .5 scale, 25/75 .25 scale and so on.