🚀 go-pugleaf

In article <15mggeINNfie@network.ucsd.edu> rama@sdsc.edu writes:
>Hi,
>
>  I have 500 images that I am sequentially displaying
>through the Render module.  I would like to capture
>each image into a separate file with WriteImg (and
>AnimFile to change the filename that WriteImg uses).
>The problem I am having is that Render and WriteImg
>are not in sync and some images are not written to
>disk at all.  If anybody has any ideas on how to
>sync these two modules so that AnimFile gives a new
>name to WriteImg just as Render sends its lattice to
>WriteImg, please let me know.

	I am not sure that it is possible to sync Render and
WriteImg without going inside Render and altering some code.


At NCSA, we wanted to "Snap" images off Render and store them
on a Laserdisc (or in a file .. ) for a time-dependent
particle flow system( or for any animation/time dependent sequence ).
The problems we ran into were:

1. Render doesn't know when its done rendering one frame. So, its
	hard to know when to trap the image( or when to fire WriteImg
	in your case).

2. Render fires multiple times if it has multiple geometries
	coming in (firing algorithm does not work if there is
	fan-in on any port). So, even if we figured out when Render was
	done, we wouldn't know how many frames it created for one
	timestep (as it would fire for every geometry it got .... ).


The solution .....

1. When is Render done? [Note: Inventor knowledge required]
	Attach a callback (Inventor) node at the end of the Inventor
	scenegraph that Render renders. This callback can tell you when the
	rendering is done. (I don't want to go into the
	details here -- email me if you want more details )
2. Multiple firings --
	Make a port for every geometry that is coming in. The next
	release of Explorer will probably have this built into their
	Render (ask the guys from SGI about that).
	We rewrote Render so we could do this (and then the nice
	folks at SGI gave us a copy of their version which we later adopted).


>
>Thanks,
>
>(in advance)
>
>Rama
>

cheers,
gautam


Gautam Mehrotra
gautamm@ncsa.uiuc.edu