[x3d-public] UnlitMaterial

[Joe D Williams]

Just logically, to me now anyway, if no light then all that is left is emissive.
The shape can emit some kind of light (glow), according to transparency, but not reflect of absorb. 
So diffuse doesn't count for unlit because that is response due to effect of lighting.
?
Joe.


-----Original Message-----
From: Extensible 3D (X3D) Graphics public discussion <x3d-public at web3d.org>
Sent: Feb 20, 2025 2:23 PM
To: X3D Graphics public mailing list <x3d-public at web3d.org>
Cc: Andreas Plesch <andreasplesch at gmail.com>
Subject: [x3d-public] UnlitMaterial

Looking at UnlitMaterial:
 
https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4.1-CD/Part01/components/lighting.html#LightingUnlit
 
Can UnlitMaterial be thought of as Material without light contributions ? Eg. on_i for all lights is 0 ?
 
It looks equivalent but perhaps there is a subtle difference. Yeah, one subtle difference appears to be that the transparency field is applied to diffuse.a rather than emissive.a .
 
Related, the Phong lighting in the case of on_i all zero, does not seem to have a way to specify an alpha for emissive ? Not sure how much use emissive alpha has but UnlitMaterial has it.
 
Thanks for any input, -Andreas
 
-- 
Andreas Plesch
Waltham, MA 02453





-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://web3d.org/pipermail/x3d-public_web3d.org/attachments/20250221/9b7e51b0/attachment.html>