Add support for gain maps

vorg commented 1 month ago

200MB exr -> 10MB jpg? Hell yeah!

Questions:

[x] is gain map support pex-renderer, pex-shaders or lib-renderer feature?
[x] can i resize the jpg and keep metadata? Does it still work? E.g. That 10MB jpg is 8k. Can i resize ldr jpg to 1024x512 and still get correct hdr? Resizing orignal hdr/exr is tricky without Photohop.

dmnsgn commented 1 month ago

Summary:

a pex-loaders feature, without any dependency other than a pex-context to recover the gainmap data
uses SRGB texture so WebGL1 support not guaranteed (but we're sunsetting it soon anyway)
resizing workflow without third party need clarifications
jpeg only for now
jpeg quality when exporting also yields further size decrease (huge drop in size from quality 1 to 0.9, possibly in the 5MB to 500kb) with little compromise on the env map quality.
I'd recommend we also agree on hdr file naming, including jpeg quality in the file naming: source-name-size-quality.ext eg. polyhaven-brown_photostudio_02-4096x2048-q90.jpg

Notes:

# Get jpeg image quality
identify -format '%Q' file.jpg

vorg commented 1 month ago

can i resize the jpg and keep metadata

No. You need to resize .hdr e.g. in Pixelmator and generate new gaim map

pex-gl / pex-renderer