- Create or improve your lightmap:
- tick Generate Lightmap UVs
- Set your desired resolution. This is the Min Lightmap resolution. You can later increase that resolution but you cannot make it smaller. It is the minimum size.
- Set source and target index. In this case I want to improve the lightmap layout. I already have a rough layout in channel 1. I want this to be rearranged. Source and Target are both 1.
- Hit Apply. If apply is greyed out you need to tick “Generate Lightmap UVs” or make any change to your settings.
- Now you need to actually set your lightmap size and the channel. You can set a larger value for the size but it cannot be less than the minimum lightmap size set above.
Don’t forget to set the Lightmap Coordinate Index. It’s your target lightmap uv index from above.