Quote from: Tangled-Universe on February 04, 2020, 05:35:13 AMGreat news Matt!
Does this mean we can save our renders with an embedded OCIO profile as well and apply LUT's in 3rd party programs?
I'm not sure if I'll be embedding metadata in the first release, but you will be able to output an EXR in something like ACEScg and then apply the conversion to sRGB (or whatever) in the 3rd party app. For explanation, let's use ACEScg as an example.
Bear in mind that
just outputting in ACEScg will only be useful to some people. It is useful if you already have a lighting/compositing pipeline that uses this colour space, but if you don't then there isn't much point. What do I mean by that? Well, if you have a pipeline that assumes EXRs are in ACEScg, then it really helps if Terragen outputs EXRs in ACEScg, otherwise it won't look right in software that assumes it's ACEScg. To make this happen, Terragen simply needs to convert from its internal colour space to ACEScg when it writes out the EXR. However,
if Terragen's internal rendering space is the same as it always was (i.e. "raw" scene linear), then this doesn't give you better renders, it just removes the conversion step later in the pipeline and avoids confusion in a pipeline where every other EXR is ACEScg.
Completely orthogonal to this, you might want Terragen to
render internally using a different colour space to slightly improve the quality of the render. Maybe it will help with some scenes, but I'm not sure yet. For this discussion let's assume ACEScg is better than linear Rec.709 for internal rendering. If we want to render internally with ACEScg, this involves more conversions at various points in Terragen: 1) Textures and colours need to be converted into the internal rendering space. 2) Previews and render views need to convert the renderer colours back to sRGB (or whatever space your monitor uses). 3) When writing images, the images need to be converted to whatever space you want them to be in, for example sRGB for LDR images and ACEScg for EXR. If the output space is the same as the internal rendering space, then this last conversion isn't necessary.
It will be Terragen's job to handle all this conversion (with help from the OCIO library), and you would choose which colour space you want for each of the following: internal rendering, EXR output, display. Using OCIO, a lot of this can be configured globally so that it works the same across all your apps, so less needs be put into the Terragen UI. But there is still a lot to get our heads around!
Another consideration is the LUT, of course. ACES has a standard dislay LUT that is a bit like TG's native soft clip, gamma and contrast, but it's more interesting. And if you're working in a pipeline that uses that LUT, you need to be able to see that LUT in Terragen's previews and render view. So that is an important component in the upcoming OCIO features in Terragen.