Dashboard_avatar
Feb 27, 2010
Post id: 301937 Report Item

Hi,
I would like the instanced objects to fade in gradually after they are emitted  in 10 frames. How do I do it ?
I have tried adding a ramp in the per particle opacity. It shows me the transparency in the shaded viewport but is fully opaque when I render it.
Thanks,
Redman

Dashboard_avatar
Feb 28, 2010
Post id: 301950 Report Item

Hi,
Well thanks a lot for the consolation. If transparency dosen't work then can we animate  each instance object from scale value zero to a random size so that theyappear to be emitted smoothly yet their sizes are different. Can someone please enlighten me with the appropriate expression. Thanks.

Regards

Redman

Thnkr4twitter
Feb 27, 2010
Post id: 301938 Report Item

The shader you apply to the instanced object  is not going to respond to any per-particle attribute. It's been a missing feature for years. Please log a feature enhancement request with Autodesk. The workaround is to cycle through 256 objects, each with a slightly different opacity.

Dashboard_avatar
Feb 27, 2010
Post id: 301939 Report Item

Well if its any consolation it CAN be done with mentalray, if ones prepared to wirte 60 lines of mentalray shader code. However the tools needed are a bit convoluted.  Anyway this has been requested year uppon year.

On the upside rendermans studio doe sthis natively.

Also 10 difefrent objects would probably suffice.

Viking_lg
Mar 01, 2010
Post id: 301955 Report Item

Whoa there... Can't you just animate the transparency value of the shader being used on the instanced objects?  Or, the Cutout Opacity value of a Mental Ray shader?  

Viking_lg
Mar 01, 2010
Post id: 301956 Report Item

Err... Wait do you mean that each instanced geo/Particle needs to disappear at different rates?

Dashboard_avatar
Mar 01, 2010
Post id: 301962 Report Item

That would be the title of the question, so yes.

Dashboard_avatar
Mar 02, 2010
Post id: 301988 Report Item

Hi,
Well yes, I need each particle to  be transparent when they are emitted & later be opaque in maybe 10 frames so that they appear smoothly rather than popping in. So animating the transparency of the shader will not work since all of them will be transparent & after few frames all of them will be opaque. It will not happen on a per particle basis.
If anyone knows how to animate the scale value as I had explained in the earlier post it would be great. 
Thanks,
Redman 

Dashboard_avatar
Mar 02, 2010
Post id: 302000 Report Item

Hi Joojaa,
Thanks a lot, I will try that.


cheers,
Redman 

Dashboard_avatar
Mar 02, 2010
Post id: 301989 Report Item

Make 10 copies of your object and give them s shader thats progressively more trasparent and swap the isntace out in isntancer. Thats the 3rd and 4th answer.

However it is possible to do this its just that autodesks mr exporter is made in a bit retarded way* and its not easy to do a shader like this. Its possible tough just  a bit convoluted. If your comfortable writing c and compiling mr shaders then i can give you a walk tough on how to do this properly.

*well thing is the mi stream seems to have absolutely no design principle behind it whatsoever, or then its designed totally wrong way around. Its not like designing it in way that makes more sense is impossible. Maybe its due to the fact that they wanted to go the bundling way but still...