What is typically more expensive?
polycounter lvl 11
Sorry, I'm still a bit new to this engine...
Quick question about the UE4 material shaders.
What is typically more expensive to use in a scene; Parallax Occlusion Mapping or Tessellation?
Quick question about the UE4 material shaders.
What is typically more expensive to use in a scene; Parallax Occlusion Mapping or Tessellation?
Replies
Literally no game I know even ships with it. The only exception is Gran Turismo, and it uses adaptive tessellation.
I recall an artist here who worked on Thief (2014) and said they used POM for some parts.
I'm sure Tessellation is the most expensive, it does require DX11 after all. I'm pretty sure a lot of implementations include the ability to adjust the amount of tessellation based on distance, so you can find the sweet spot for up close shots and let the engine handle the far away stuff.
That's not true, Dirt 2 and Aliens vs Predator both had tessellation and came out in 2009-2010
With that said, if you're trying to compare them from the standpoint of, "Which should I use for this asset?" you'll probably arrive at the right conclusion by looking at the visual trade-offs rather than the performance ones.
Typically you're three options are:
Tessellation - Can be cool or complete crap depending on the object. Can look great on rocks and other organic surfaces, looks terrible on anything precise or hard surface. Actually adds and alters geo, so your silhouette changes and there's no smoke and mirrors. Also, tends to be hard to control, optimize and tweak.
Parallax mapping - Bump Offset in Unreal land. It's smoke and mirrors, just like normal maps. Doesn't alter your silhouette, so it falls flat at shallow angles. Also requires some camera movement since it's a parallax effect. Doesn't add geo, so you're not going to get vert-bound, good for large surfaces like floors and walls.
Just Model It © - Yeah. Just spend the triangles. Major con is that it potentially takes longer depending on your pipeline or workflow. Costs extra geo, but it's easy to optimize and tune unlike tessellation. May cause a little bit more of a memory footprint from storing extra verts, especially with a 2nd UV set for lightmaps, but current gen hardware is probably going to be bottlenecked by other factors first. Also benefits from traditional LOD's and occlusion culling.
If you look at some of the UE4 samples, they have polycounts somewhere between 250k and 1 million triangles. The highest I've seen is 6 million triangles being rendered in the Effects Cave.
I love this!
Just like when I was heavily into StarCraft II. People came up with all these sophisticated strategies to counter this and that, and expand here and there, until a pro realized "Just go kill him" was the best strategy
Sorry, totally off track, I just thought this kinda reminded of the same scenario