Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] General Discussion => Topic started by: Tanakov on 2014-01-24, 10:34:22

Title: Refraction - Map
Post by: Tanakov on 2014-01-24, 10:34:22

Hello
I was wondering this for quite some time, sometimes I render objects that are behind glass or other refractive objects that need some post or tweeking.
I always have problems with masking out this type of objects.

One of my "solutions" in Vray is to rerender the scene in black with only the glass and the object materials unchanged (sometimes I just change it to white light and disable glass reflections)

Its possible to do exacly the same thing in Corona, but I dont like that method. Does anyone have better way to do this?

Title: Re: Refraction - Map
Post by: astudio on 2014-01-25, 12:08:46

i use Render Mask script from Requiem Scripts. There must be some render element for this, but I didn't check it yet.

Title: Re: Refraction - Map
Post by: LKEdesign on 2014-01-25, 18:43:32

Would it be possible to add an option on the MatID, ObjID, Alpha, and Zdepth channels to disable or look-through transparent objects?

I work often with interiors that have many levels of glass, - and I often meet this challenges, that half of the objects I want to adjust is behind one or more surfaces of glass. Only way currently is running two renders, where one of them have the glass hidden. The option above would be abig time saver.

Title: Re: Refraction - Map
Post by: Utroll on 2014-01-25, 20:59:45

Solving that problem is pretty hard I guess.

It's all about coexisting object in a same pixel. While alpha is using black and white, use of greys represent a pretty good approx. of an overall transparency.
But when it's about more complex data problem starts. Like storing multiple zdepth in a given pixel (Z-the glass, Z-behind the glass, Z-reflected in the glass) each time a ray meet glass. Exr is souple enough to manage that but that would be 1-big and 2-severe gymnastic to process : dedicated plugin required.

May be a zdepth weighted by influence of 'most represented' pixel ?
Solving that problem is a kind of Graal quest as far as I know (not much). Render solving that would be a king.

Title: Re: Refraction - Map
Post by: Tanakov on 2014-01-27, 07:53:25

So we have a to send Keymaster for the quest of refractable Zdepth!

Who ever finishes the quest will be crowned.. so corona.. crown.. king... damn that can work!