General lightmap/baking questions I can't find a definite answer to
polycounter lvl 9
These are mostly general lighting questions that can apply to most engines, but since I'm working in Unity, I'll post here:
1. For all my assets, Ive just set them to generate lightmaps. After I bake, I get an error stating that 2000+ items have overlapping UVs. Though the bake looks fine. Do I need to worry about making custom lightmaps for all of these assets, or is it more "if it looks fine, its fine."? Or do overlapping UVs in lightmaps cause any performance issues?
2. I've been baking my lightmaps at 1024 per lightmap, and I get around 10 full lightmaps for my level. Assuming the number of lightmaps doesn't really matter, but does the resolution of the lightmap matter? At what point should I bake 2048 lightmaps instead of 1024?
3. I have a lot of metal throughout my level. Should I set a reflection probe for my entire level, and then just use other reflection probes for certain things? Any downfall in setting one giant reflection probe to encompass my whole level?
4. When should I be baking the directional light? I see a lot of people dont bake directional lights, and Im assuming thats just because it needs to be real time for character shadows etc. Is this correct thinking? Isnt the directional realtime light just causing realtime shadows on EVERYthing in the level? Isnt this expensive?
5. How can I bake just a specific area in Unity for testing? Setting the Prioritize View in Lighting Settings tends to cause a bake crash when using GPU Rendering. Besides, even if I click Prioritize View, it will still bake the entire level after it bakes the camera view. Any way to do this?
Thanks for your time!
1. For all my assets, Ive just set them to generate lightmaps. After I bake, I get an error stating that 2000+ items have overlapping UVs. Though the bake looks fine. Do I need to worry about making custom lightmaps for all of these assets, or is it more "if it looks fine, its fine."? Or do overlapping UVs in lightmaps cause any performance issues?
2. I've been baking my lightmaps at 1024 per lightmap, and I get around 10 full lightmaps for my level. Assuming the number of lightmaps doesn't really matter, but does the resolution of the lightmap matter? At what point should I bake 2048 lightmaps instead of 1024?
3. I have a lot of metal throughout my level. Should I set a reflection probe for my entire level, and then just use other reflection probes for certain things? Any downfall in setting one giant reflection probe to encompass my whole level?
4. When should I be baking the directional light? I see a lot of people dont bake directional lights, and Im assuming thats just because it needs to be real time for character shadows etc. Is this correct thinking? Isnt the directional realtime light just causing realtime shadows on EVERYthing in the level? Isnt this expensive?
5. How can I bake just a specific area in Unity for testing? Setting the Prioritize View in Lighting Settings tends to cause a bake crash when using GPU Rendering. Besides, even if I click Prioritize View, it will still bake the entire level after it bakes the camera view. Any way to do this?
Thanks for your time!
Replies
2- I would probably use 2048. Objects will different lightmaps will not batch, so its more efficient that way.
3- Its a tradeoff for more accurate reflections vs performance. Objects will different reflection probes will not batch. If you have say, a red room and a green room, obviously you will want different reflection probes for that because it will look wrong if you just have one. You could also consider using screen-space reflections.
4- Depends on the light setting- it can be baked, mixed, or realtime. The mixed behaviour will depend on your lighting mode in your light settings. The best one is probably "Distance shadowmask" where shadows are realtime up to a certain distance, and then use baked lighting. See- https://docs.unity3d.com/Manual/lighting-mode.html
5- I don't think you can do this.