9

906 Glossary

Additi ve Opacity

Anadditiveprocessaddstwovaluestogether,such

as two colors. When yo u add colors in 3ds Max,

the result is brighter than either of t he two original

colors.

Additiv e Opa ci ty

Sphere on the right uses additive opacity.

Additive opacity brightens the colors behind the

material by adding the materia l’s colors to the

background colors. Additive opacity is good for

special effects such as lig ht beams or smoke. You

specifytheuseofadditiveopacityontheExtended

Parameters rollout (page 2 –1471).

Additive Opacity and the Alpha Channel

By default, additive opacity does not gener ate an

alpha value. In other words, the a lpha value is zero,

indicating no transparency. This gives correct

results with backgrounds in renderings, but if you

want to composite o bjects with additive opacity

using video post or a compositing program, you

mightwanttohaveadditiveopacityrenderwith

transparency.Todoso,addthefollowinglineto

the [Renderer] section of the 3dsmax.ini file, and

then restart 3ds Max:

AlphaOutOnAdditive=1

To rever t to the default method of rendering

additive opacity, in the 3dsmax.ini file, change the

val ue of AlphaOutOnAdditive back to 0 (zero),

and then restart 3ds Max.