matte again

[bluescreen2]

many of you say to use matte = -1.
i am wondering, whats the differecne between
matte 1 / 0 / -1 ?
any thoughts?

thx,

blue

[vlado]

When the alpha contribution is 1.0, the alpha channel for the matte object is normal. E.g. if the object is opaque, the alpha is white; if it is fully transparent, it will not influence the alpha channel at all.

When the alpha contribution is 0.0, the object does not influence the alpha channel at all, regardless of its actual opacity, although it is present as normal in the RGB channel. (This option may also be used to simulate the "Render Occluded object" option of the scanline renderer).

When the alpha contribution is -1.0, the object's alpha is cut out from the alpha of the objects behind it. E.g. if the object is fully opaque, its alpha will be black and blocking the alpha of objects behind it; while if the object is fully transparent, it will not influence the alpha at all.

Note that an object doesn't have to be a matte object for this setting to work; you can change the alpha contribution regardless of whether the object is matte or not.

Best regards,
Vlado

[bluescreen2]

wow. thx vlado for your quick and good explanation.
i am realy lucky with vray and your team.

you guys rock !