Import 16bit normal map fails...

[Onkelpoe]

hi,

when I try to import a 16bit normal map into a "TN" layer, I get:

Code: Select all

L3DTio_FI::LoadMapFile error
 - unsupported bpp/mode for file type 'png' (bpp = 48, mode = 9, map type ID = 4)
CImportMapDlg::OnBnClickedOk error:
 - cannot load map file

Why is that?

Tried different settings, like RGB color, RGBA, 16-bit integer, Normals map and so on - but non of them worked...


Cheers!

[Onkelpoe]

so nobody got this issue?!

Judging by the log, I think L3DT can only read 8-bit pngs propperly - but png can also be 16-bit!

[Aaron]

Hi Onkelpoe,

Sorry for the delay, and yes, no-one else has reported this as an issue before. L3DT's PNG plugin only loads PNGs as 16-bit for single-channel greyscale heightmaps; RGB and RGBA images are always loaded as 8 bits per layer. This is because L3DT internally only holds normal maps and RGB(A) colour maps as 8 bits per layer in memory, so importing/exporting 16 bit per layer RGB(A) images wouldn't improve the bit depth of the actual data.

Can you tell me which applications use 16-bit normal maps?

Best regards,
Aaron.

[Onkelpoe]

Hey Aaron

I wanted to use the 16-bit normals for higher precision in Marmoset Toolbag2 / Unity5 renderer. At least provide them in 16-bit (could be reduced
to 8-bit anyways)

So I guess it would be hard/too time consuming to make L3DT load 16-bit normals (RGB) png and I have to scale them down to 8-bit?

Best Regards!

[Onkelpoe]

Can you confirm that, Aaron?

[Aaron]

Hi Onkelpoe,

It may not be too hard to add 16 bit per layer RGB import-only support to the PNG plugin. Could you please send me an example 16 bit per layer PNG normal map file? (to aaron@bundysoft.com). It would help with testing.

Best regards,
Aaron.

[Onkelpoe]

Yes, I could send you one/provide a drop box link...

But before, let me ask if 16bit support maybe added for importing, but not for export/exporting overlapped tiles or
export with optimized mesh?

Cheers

[Aaron]

Hi Onkelpoe,

I wasn't planning on exporting 16-bit/layer normal maps. It's probably only a little bit of work, but I'm not entirely convinced it would be useful in L3DT. Since L3DT generates normal maps at 8 bits/layer, you don't get any extra precision if you export the files from L3DT as 16-bits per layer. What you'll actually get is every second bit in the image being zero. 8-bit data will still have (up to) 8 bits of precision, even when saved in a 16-bit container.

However, I'm happy to add the 16-bit normal map importer, as it may be useful for compatibility reasons.

Cheerio,
Aaron.

[Onkelpoe]

Ok, I understand!

Thanks for reply and have a good time - cya