Baking position data to EXR is clamped/LDR

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hi, i have a VAT-like system where i need to bake out position data kinda like vector displacement.
i'm using labs maps baker and tried a custom attribute bake, but the EXR data is clamped (at least the negative values are).
i tried using the vertex color (Cd) option but same results.
from what i understand, just by using a HDR format like Exr is sufficient for the baker to output correct data (i.e: 32 bit float).
when opened in PS the file is indeed 32 bit but the negative values are not there.

looking at the data in houdini spreadsheet i see that it is correct both in terms of type of data and the values (negative values and above 1).

does anyone have any idea why this is happening? am i missing something?

there is a merge node that throws a warning something about attributes not being initialized properly but checking the data before and after the merge node i see no difference...
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If you open the .exr in mplay or in COPs are the negative values also clamped?
Tomas Slancik
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Method Studios, NY
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yes

looking at the nodes inside maps baker it seems they are normalized even if they are not "clamped" by the filetype. there's also a convert node in cops for all maps that converts to 16 bit for some reason. i guess it makes sense for games that 32 bit textures are overkill, but what if you want to bake out something more precise like position or normals...

i need to evaluate if i really need the HDR values or if i can accept the loss of precision, else i need to "gut" the baker or make my own.
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