Racer v0.8.16 has a time-of-day editor, currently including 18 variables to track. The release is at http://www.racer.nl/download/racer0.8.16.zip . The editor starts up immediately (data/scripts/oncar.rex). You can add new points and move them vertically. Dragging them out the graph vertically will remove them. I'll need help with getting a nice base. Specific problems: - sun x/y/z - specular rgb - leave it just as diffuse rgb or really define it separately? Known issues: - adding a point seems to be a little difficult at the extreme left & right Also it would some day be cool to use the sun direction for the clouds; for that you'd need to have clouds rendered and have a normal map that describes the cloud direction. This could generate nice sunsets.