A little problem with Valve that they didn’t make normal documentary every element in SFM, for example, flexes and today we are going to talk about tessellation. You can’t find any information about it (only on Valve Wiki) and you will hear my information about it.
Tessellation is used to manage datasets of polygons and divide them in real-time rendering using a subdivision method. Goal is make smoother model. Example on the picture from Wikipedia.
Current feature works on DirectX11 and OpenGL 4. If this option is available in any game, you can turn on and you won’t see any vertices or low-poly models. Last time this feature available in games, but not always.
We all know that SFM works on old Source engine with DirectX9 + 32-bit, but you can find out that tessellation works here. If you tired to smooth edges in Photoshop, you can use tessellation, but it won’t work on any model. Maybe will work on objects, but you need to test with character. What about plus and minus from feature?
+ Control level of tessellation with command mat_tessellationlevel <1-16>
+ Model will receive good lightning and will use a subdivision method
- More level of tessellation, more load on GPU
- Can crash your SFM because DirectX9 and 32-bit exe
- Can be problems with compilling model with $subd
- Studiomdl will crash if model will have any triangles. $subd work only with quads.
Adding tessellation to your model
If you have your own model, which you modeled, first make sure that there is no triangles on the model. If you have it, try to convert them to quads. You will need addon which you can import and export smd/dmx format. For example, I use Blender Source Tools for Blender. Be sure to export model in dmx format, because smd convert to triangles by default, but dmx can export in polygons and triangles. After that make QC file and write what you need. You can find information how to compile and decompile models. Just google it.
In QC you will need to put $subd before model name. $subd will turn on tessellation on the model.
If you receive errors or crash in compiler, that mean you have triangles on the model or something else.
Adding tessellation to the model from Internet
I was trying to put tessellation on some models, but problem was a lot of triangles on the polygon, which can’t convert to quads. Only way is make retopoligy. I know - this will be long time to do that, but it’s only way. After retopoligy you will receive model with quads, but you will need to add flexes, bones, etc. Most of problems on the characters, so less problems will be with props.
Few people know these features because of Valve’s attitude and can’t find good documentary. This element need to add everywhere and characters or objects will be more smoother and poster will be beautifull.
P.S. - I really like that @aeridiccorensfw is trying to put this feature on his model and he made new monthly update post, where he wrote some problems with tessellation.
Read it here -https://aeridiccorensfw.tumblr.com/post/173417340642/april-update-post
You can subscribe to him too. He is making good stuff.