References, Instances, Duplicates.. all crap

[naughty]

I have a script which generates trackside objects from a library.. The users build a track layout using curves, tag certain curves as being an object type (e.g. a fence, barrier, or row of traffic cones, etc...)

when they're happy with their track layout, they hit a "Generate Geometry" button, which loads in the related object from the library AS A REFERENCE, then INSTANCES it at every relevent point along the curve.

My problem is, it takes 10+ minutes to generate the geometry on a track when I use INSTANCES. However, if I change the Script to generate DUPLICATES instead of INSTANCES the geometry generation only takes about 30 seconds... and this is always the case, it's not just on a particular scene..

What the hell is going on with Maya and instances..??!? if anything, surely they should generate QUICKER than duplicates..

can anyone shed any light on this problem...?

Ideally I'd like every instance to be an individual REFERENCE, but this just fills up the hypershade with hundreds of duplicate referenced materials, making it impossible to use.. AND Maya spends ages LOADING in every reference INDIVIDUALLY (even when it's the same file) each time you load the scene up...

:nathaN

[failure]

Post the code

[naughty]

There's really no need to post code, as it's easy to just knock up a basic loop to prove how bad this problem is...

{
int $inst = 1;
string $obj[] = polyCube;

float $timerStart = `timerX`;

for ($f=0 ; $f<1000 ; $f++)
{
	if ($inst)	instance $obj[0];
	else	duplicate $obj[0];
}

print ("nElapsed time: "+`timerX -st $timerStart`+"n");

}

try running this which simply generates a 1000 copies of a cube (change $inst from 0 to 1 to swap between dupes and instances)

on my PC it takes 0.54 second to generate a 1000 duplicates, and anywhere between 6 and 11 seconds to generate 1000 instances.

[joojaa]

Actuly in general instances are a bit sower than copies they just use less memory.

[naughty]

a BIT slower?!? on some scenes I'm getting a 1:100 ratio of slowness!!! a hundred times slower for instances is just crazy...

[joojaa]

Well sure but you must understand that the underlying tjing is also wastly different. Your creating symbolics of symbolics... They need to be updated to 1 node more!

Furtermore for each object separately. Does grouping and instancing the group do any difference?

[joojaa]

Also reference do have a option for not bringing in duplicate shader nodes? atleast ive seen one.

[hansesurfer]

I also had that problem..

instances are so sloooow...

I actually thought instances were made so you can have masses of identical objects in your scene. But producing instances takes A LOT OF TIME and its really funny that a scene with many instances is much slower than a scene with simple copies.

maya wasn`t made to deal with many instances, so if you need to have many identical objects (>1000), bye 4 gig of ram and use copies instead...

[joojaa]

Or use particle instancer instead! it can handle wast amounts of isntances quickly. Much quiker than what intance command can.

Additionaly doing posts with it along a apath is super simple all you need to do is make a new shape from the old one rbuild it linear uniform with as amany segmens as you need turn softbody and run instancer.

[naughty]

you don't half talk a lot of waffle at times JooJaa but it looks like you've come up trumps again with this "particle Instancer". I've never heard of or used it before, but I've just had a look and done a quick test and it seems to be almost too perfect for my requirements to be true..!! looks like you've saved me a lot of hassle. thanks.

:nathaN