CompuServe Thread

#instance and the rendere

7 messages in this thread
#168378From: Tim c BrananMay 5, 1995 12:51 PM
How does the renderer treat an instance? Does it consider it to be like any other object, or does it have any special considerations? Is it better to make 1000 instances each of 6 objects, or 6000 instances of one object? The reason I ask is related to the question I posed to you yesterday about the 'can't allocate object instance' problem. I tried the file again, after I had remmed out some unnecessary drivers in my autoexec.bat and config.sys, and the error message didn't pop up, but It sat at the same exact place (the gas gauge was on 'preparing normals' and the line was 4/5 across the screen) from a few minutes into the rendering until 16 hours later when I finally gave up and hit the reset button. There was a gig free when I started, and 40 meg free when I checked the drive after re-booting. The master object I made the instances off of had a little over 1000 faces. I tried another file on another computer with 4096 instances made from 4 copies of one object with 488 faces. This rendered fine without crashes or anything weird happening, though it did take about 90 min to render each frame, but I was expecting that. Both computers have 64 meg ram and about 1 gig free hd space. What can you suggest that might shed some light, or make my life easier in some way? Dealing with this many objects is greatly tiring. Thanks.
#168529From: Yost GroupMay 6, 1995 10:39 AM
It's a good question. Most people don't realize that all instances are expanded out into full geometry inside of the renderer, so if you've got 4096 instances of a 488-face object, the renderer will be looking at 2 million faces! The two things that instances "buy" you are small .3DS file size and the ability to change the editor master object and have all the instances change in the keyframer. – G
#168592From: Tim c BrananMay 6, 1995 6:29 PM
>>>The two things that instances "buy" you are small .3DS file size and the ability to change the editor master object and have all the instances change in the keyframer.<<< Well, the small file size make it worth using instances in this case. I'd never be able to manage these files without using instances. Before I spent all my time waiting for files to save and load, now it is no big deal. I can fit the files on floppies even if they have 20 thousand trees in the file. Unfortuantely there is still the problem of rendering. 5000 trees seems to be the useful limit per scene. After that, the rendering time becomes too high and the machines start to flake out from too much swapping. Frankly I am amazed I was able to pull this project off at all.
#168634From: Yost GroupMay 7, 1995 12:36 AM
With that much data being expanded into the renderer, you're really pushing the hardware HARD. (I like to see that pioneering spirit! <g>) – G
#168638From: Tim c BrananMay 7, 1995 1:25 AM
With all the time and effort I put into this, I wish the end result were more visually striking than trees on a terrain. Nobody will appreciate the time and effort and the fact it is real world data behind the image. Maybe this is a job for R5. (hint, hint) (G)
#168754From: Yost GroupMay 8, 1995 12:18 AM
I shudder to think of how much memory a scene like that would take under NT, with all the extra overhead. – G
#168757From: Tim c BrananMay 8, 1995 12:33 AM
It's taking about 400-500 megs now, so unless NT hogs memory exponentially, I don't see it making a big difference, but I haven't used NT personally yet, and of course I can only guess what might be in store for V5 of 3ds. I doubt it would help me any in this situation. What I need is more RAM, or some trick I haven't thought of yet to simplify the scene.