Howto:Multi-channel lightmap: Difference between revisions

This documentation is intended to be a step by step guide to produce lightmaps for FlightGear using Blender and Gimp. It is not intended to be a comprehensive tutorial on the use of Blender or Gimp, just enough to get the job done. Anyone with expert skill in either Blender or Gimp is more than welcome to add to this guide with more details, techniques and tricks.

Start by setting up your lighting scheme in Blender.

Create the light sources you want to map (bake) in your blend. You can have up to 4 lightmaps per multi-channel light map in FlightGear. Each of those four lightmaps can be a single light source or a combination of light sources. In other words, you could potentially have 2 lights on the left combined into one lightmap and two on the right into another lightmap, leaving 2 channels open for 2 more lightmaps of any configuration.

[[File:Blend6a.jpg|thumb|Setting up colored light sources]]

You can set up your lights to mimic the 3 color channels used in the shader and thus bake three different light sources into three different channels in one bake session if you wish. This would eliminate some steps in Gimp during the next part of the process, but for the purpose of this tutorial, we'll take the longer approach so you can see how it is possible to work with images and their channels. This is what you might expect to see if you do a light source per color channel (rgb).

[[File:Tutorial 01.jpg|thumb|Selecting object to map in the blend]]

[[File:Blend1a.jpg|thumb|Create an image to bake to]]