With colour spaces there are at least three key points in the pipeline where they need to be considered carefully. 1: Input of colours via the GUI or texture maps. 2: Rendering (independent of input or output). 3: Output.
I think it's important for Terragen to be able to output renders with "wide gamut" colour spaces. However, until Terragen has the ability to easily render these colours there isn't much point, because any 3rd party tool that knows these colour spaces should be able to easily convert from RGB to those colour spaces. But I plan to experiment with rendering in different colour spaces in future, because that could yield some colours that are outside the RGB gamut, but also richer lighting even within the RGB gamut. And then you'd need a wider gamut colour space to output the image.
The first thing I want to support is ACES, and possibly other colour spaces via OCIO (OpenColorIO). For internal rendering (independent of the final output space) there are probably better choices than either ACES, RGB or XYZ.
I don't know anything about DCI-P3 yet. Why is this an important colour space to you?
Matt
