Re: geomview-memory fountain

[slevy]

> From mossip at vizlab.rutgers.edu Wed May 13 15:45:43 1992
> Date: Wed, 13 May 92 16:47:12 EDT
> To: software@geom
> Subject: geomview-memory fountain
> From: Paul Mossip <mossip at vizlab.rutgers.edu>
> Sender: mossip at vizlab.rutgers.edu
> 
> Greetings,
>    We are using geomview to view a OFF file type and then single frame render
> onto video tape.

> #1   I have noticed that if you sent multiple OFF files (through the named
> pipe (-M) system) that the memory taken up by each geom is never released.

Right, this is a bug.  We do attempt to release memory, but the reference
counting scheme isn't quite consistent.  It's partly fixed in the release about
to come out (1.0.2) -- if you copy a series of geoms to a named pipe,
or repeatedly define a named object, memory is reclaimed properly as each
new geom replaces the old one.  However unfortunately it doesn't yet work to
use (delete ...) and (new-geometry ...) to load a series of frames.  I haven't
been able to pin this down.

Still I think you can get the effect you want with

	#! /bin/sh

	mknod  somepipe  p
	geomview -c somepipe &

	echo "(new-geometry  thing  { : somename } )" >somepipe
	echo "(merge-ap thing { ... })" >somepipe
	for f in yourfiles.*.off; do
		echo "(read geometry  { define somename "
		cat $f
		echo "} )"
		echo "(update-draw Camera)"
		echo "(! animate -r)"
	done > somepipe

i.e. displaying a named geom object, and repeatedly redefining the value of
that name.  *In the new release*, this works correctly.


>bug#2
>  when running geomview under twm and 4Dwm geomview does not always properly
>get the focus of mouse input.

Is this the bug that appears when you've just popped up an input panel,
and find that it doesn't accept keyboard input until you move the mouse out
and back into the panel?  This is also fixed.

>thing#3 
>  If you change the lighting(from the default) it is not saved when you save
>the state (mainly since lights are not defined in your command language) Is
>there a hack to be able to load different lights or is this on your todo?

The new release saves lights, too.  I can't think of any way to dump
out modified light settings using the old release.

You can load lights using the "lighting" clause in an appearance.  It's best
to install them in the viewer's "base" appearance.  E.g. the default lighting
setup could be re-created with:

  (merge-baseap {
    lighting {
	replacelights
	ambient .2 .2 .2
	light { color .6 .6 .6 position 0 0 10 0 }
	light { color .5 .5 .5 position 0 1 -1 0 }
	light { color .4 .4 .4 position 1 -2 -1 0 }
    } 
  )

> Overall we are very impressed with the performance of the geomview package (we
> used the minnieview package before) and we hope to be able to use this to
> render most images instead of having to raytrace them with art.

> -Paul Mossip

Thanks for your interest!  I will let you know when the new release is out.