a. Glyphs create a bunch of new geometry, so they suck memory down
pretty quickly. You could try setting individual modules at and below
Glyph to "Cache:None", or try a simpler glyph (cube instead of sphere,
for example). I suspect most or all of your errors are the server
running into the wall on memory. DX dies rather ungracefully. Might
almost be better to get a handle on how much you can do, then do an
intentional Disconnect from Server, reconnect, about the time memory is
getting thin. This doesn't help much in the middle of a long time
series, though, so...
b. I would never ever think to use DX live except in the safety of my
own office. Course I've been a happy Mac user since 1984, so I've had
the advantage of Quicktime since about 1992. I would generate movies
frame by frame (forget the frame rate baloney in DX: you have no real
control over it), then drag and drop each folder of frames (logically
named to retain order, naturally) onto an empty QT Pro movie. This
makes a movie. As in, you're done. Save it, then when playing it, set
QT Pro to "Play All Frames". This will ensure that no frames get
skipped as the computer tries to play back; this method gives no
particular control over frame rate, but what do you care? You're seeing
all the frames which is what matters. You have the advantage of being
to use arrow keys to step forward and back, drag instantly to any place
on the timeline, etc., thus making really nice and quite interactive
demonstrations. It's trivial to add titles, superimposed subtitles, and
audio if needed. Naturally you can't foresee all possible audience
questions, but you can probably cover most of the bases this way. Then
if needed, fire up DX to answer the remaining obscure questions. QT Pro
is still only $30 from Apple, for Mac and Windows. I don't suppose
they've ever ported it to Linux, sad to say (and not sure why).
Sorry, I don't use Linux so I haven't kept up with equivalent movie
making tools, but I assume there's something similar. You should be
able to make ImageMagick movies and play them with 'animate', yes? It
didn't have all the same controls last time I tried it which was some
time ago, but better than a sharp stick in the eye.
On Wednesday, January 15, 2003, at 09:19 PM, Brent Wood wrote:
I have a DX application showing 12 yrs of commercial fisheries catch
data.
(about 100,000 records)
It shows glyphs for each catch with color/size set interactively to
show
catch size, vessel type, nationality, bycatch, time of day, etc.
A single session may involve 5000 images being presented, but I can
seldom
get more than 100 without an error like:
Exective:0: invalid data: Object deleted too often! (or not an object)
or
Invalid data: Deleting object of unknown class
or
Invalid camera angle <tho note that the camera is fixed for the
sequence>
or
Bad parameter. Resolution must be a positive integer
The fix is to stop/start the server & it runs OK until the next crash.
I have 1Gb of memory installed in a P4 2400Mhz, running Mandrake Linux
v9.0 DX is started with memory limited to 900Mb, the crashes appear
almost
certain when > 800Mb is used, but can happen with 600Mb used.
I have used simple glyphs & turned Image caching off to reduce memory
useage.
Any suggestions as to how to make DX more robust for presentations of
the data visualisation appreciated.
The second problem pertains to the throttle settings.
My system can show a year's data in about 20 seconds. I'd like to have
it controllable to about 2-5 frames per second, but the throttle
setting
for the image (either by the config dialogue for the Image module or
the
window dialog) seems to have a mixed effect.
At a value of two, it shows roughly one frame per second. At a value of
one it shows between (estimated) 3 and 9 f/s, the speed seems to vary
at
different times, poss due to other processes kicking in, (but I can't
find any such processes).
Is there a way I can control the frame rate accurately & reliably
(like I
expected the throttle setting to do)?
Thanks,
Brent Wood
Chris Pelkie
Vice President
Conceptual Reality Presentations, Inc.
30 West Meadow Drive
Ithaca, NY 14850
