can I turn off the ‘Premultiplied Alpha’ setting for all Bitmap slots in my materials?
here’s my listener read out when I do it manually:
meditMaterials[1].materialList[26][#Maps][#Diffuse_Color__env_piazza_brick_dm__env_piazza_brick_dm_tga].preMultAlpha = off
how could I apply this to all my Materials?
thanks!
certainly you can… the question is what are your all materials?
Some are multi-sub-objects (upto 95 ids) with bitmaps applied to Diffuse
others are Standard Materials with bitmaps applied to Diffuse
These materials are not named with a convention, some are ‘Building_Materials’ others are ‘asdf’ or ‘08-Default’
I was hoping maybe, for something like: for all Bitmap textures Premultiplied Alpha = 0 (haha, I dont know much scripting)
edit: None of these materials are using an Alpha Channel for transparency
why am i asking? the preMultAlpha is bitmaptexture’s property. we can get all bitmaptextures from the scene using getClassInstances method, and change the property. but is it really what you want to get?
When a bitmap is applied to a material slot, the default is to apply the alpha channel (if available) as Premultiplied. This makes my material render much lighter than the texture really looks, I always turn off Premultiplied when I add bitmaps. But I’m now given a file with 100 or more materials all set to Premultiplied so the renders look washed out.
I have a work around, but yes, I’d like to turn Premultiplied off for all used bitmaps.
I dont understand the getClassInstances method – I’ll look into it – thanks
for m in (getclassInstances bitmapTex) do m.preMultAlpha = off
alternative, slightly shorter and theoretically faster version since it’s just 1 property changing:
(getClassInstances bitmaptex).preMultAlpha = off
whether it is actually faster or not, it’s probably too close to tell so it’s a matter of preference
This getClassInstances “thing” seems great! Never thought of this before. Thanks!
Everyone thanks so much – totally blown away by how one line of code can save so much time – you’re brilliant!
My quess is the shorter one is faster as it is using as it is using C++ to do the loop instead of Max Script. You would probably need to loop trough a 100 scene to be able to see the difference.
You mean compile a .dll using C++ accessing the core functions?