Should I create the LOD objects manually or...
polycounter lvl 6
Hello.
We know that there are objects in far distances which are low poly, those are called LOD objects and will be replaced with a high poly object (or original object) when camera goes near them.
The question is should I create them in 3DS Max or let Unity3D automatically generate them (is it even possible)?
EDIT: This question has been edited.
We know that there are objects in far distances which are low poly, those are called LOD objects and will be replaced with a high poly object (or original object) when camera goes near them.
The question is should I create them in 3DS Max or let Unity3D automatically generate them (is it even possible)?
EDIT: This question has been edited.
Replies
Two questions:
1) Really how many LOD levels are effective for performance? I saw games with 2 levels and some other games with 9 LOD levels!!
2) Is Unity3D able to make LOD meshes automatically? once I google searched and found nothing useful.
The number of LODS should be determined by the technical artists and programmers, taking everything else about the graphical level of the game in consideration (number of objects on screen, texture sizes, visual effects, etc).
Also shaders typically have LODs too, since they're often the bottleneck for performance. So your lower LODs have simpler shaders, not just simpler meshes.
also zbrush's decimation plugin might be worth a look? you can go pretty low with that and still maintain the shapes but the geometry won't be so clean anymore. i think it keeps the UVs though.
i had more success with both these than any of the max builtin optimizers.
As stated Unity cannot generate LOD meshes but it auto creates an LOD component for you.
http://docs.unity3d.com/Manual/LevelOfDetail.html
I NEVER create LOD's manually I always use ProOptmizer. Even for characters.
Another thing to consider is using simpler shaders on the LOD models in game. This can sometimes save more CPU / GPU time then mesh reduction. For example LOD0 has has all features, LOD1 has no normal mapping calculations, LOD2 has no specularity.
Also if it is true, than it must be hard to reduce the original polycount as much as possible WHILE still maintaining the original shape of the object as much as possible and simultaneously STILL mainting the original UVs? right, sometimes the UVs layout prohibits you to reduce the polycount further even if the mush shape would still allow you? Its a "balancing game"?
Here's my thoughts. Use auto generated methods, do a quick inspection when it's done. Then be sure to only fix bugs that are reported back to you. LODs, by their purpose, are hard to inspect. Don't spend more time or stress on it than needed.
MONSTER, thanks but i meant that in general is (at least in game industry) a general rule to have the same UVs shells as the "hero" mesh also for the LODs? Or is it more common that LODs have their own UVs shells (and thus their own textures?)
I've seen some games use a new texture set for LODs, when the shader was complex. But this is usually a waste of memory, and a waste of effort. Like Monster said, only spend extra time on LODs if they're noticeably terrible.
Given good UVs I've found if you build the highest and lowest couple of LODs manually, simplygon (or others) will do a pretty impressive job of filling in the gaps.
The UVs are absolutely vital to this working but it means you can have some seriously cheap LODs at the bottom end where it's most important
Numbers wise - 7 levels was about average for modular assets on the last 3 games I worked on (PS4/XBone era ) but it would depend on the tricount of the highest LOD