Just a headsup for the Forest Thread Denizens – I’m going to start combing through this thread and the other tree instancing / populating / shading threads and apply those techniques to cityscapes.
You can find the new thread here!
If you have any suggestions, let me know!
I’m investigating particles for instancing out grass on massive areas.
Has anyone had much experience with emitting particles from surfaces and using teh sprite wizard to assign the grass?
From my own tests it seems quite promising but the assignment of the particles is too random, if it were more uniform then this would be a great method.
You should add a ‘RadialField’ node to your particle node. That will enable you to control a repulsive force between each and every particle. So when particles spawn too closely to (or even intersecting) each other, they will push themselves away, kinda like magnets with equal poles.
When you run the particle spawning process through enough frames, you’ll end up with a much more even distribution. It’s pretty cool to watch actually. 
I also tried particle instancing for massive spreads. Specifically, rvInstancer. I believe you’d need a much more powerful computer to do this on a decent timeline; it took nearly 20 hours to populate 1,000 instances on my home computer @ 2.5GHz, and particles are a single-threaded task. I’ll try it again on my shiny 1100T at work, but thus far rvInstancer is not a usable tool for me.
Particle instancing by hand would work fine, of course. But how does one control the y-rotation? Select all instances, then randomize that attribute afterwards?
I also try to populate the ground with particles but my life is not more long for to see the operation stop.
Here’s another new script which may be very helpful in populating and spreading grass, trees, and rocks:
I’ll give it a try tonight and see how it goes!
There’s a built in geometry layout tool, you need to have the Bonus Tools installed. Then under paint scripts you have a tool that uses the artisan brush to instance a set of geometry on an active surface. Try using a low res stand in for your paint reference object.
Appreciate the input, but the Paint Geo tool is hopelessly inferior to spPaint3D in all ways. We covered this on page 3 or 4 perhaps. There are some times when you’d like to connect your instances to verts/faces/edges, but spPaint’s raycast placement is far superior generally and you’re not tied down by poor-quality geometry; you don’t have to pre-think your components to make it work flawlessly, to sum it up.
Every scattering method has its pros and cons, but thus far they ALL get eaten alive by Maya’s single-threaded dependency graph. And I have the same beef as Dario on the particles topic - just tried using rvInstancer on my 1100T at work here, and anything higher than say 100 instances just takes way too long. Not only is it single-threaded, my faster CPU here seems to not care at all that it’s any faster than my home computer. And I don’t need 100 or even 500 instances, I need thousands if not 100,000 outright.
If it’s faster to place them all by hand and simply randomize scale and rotation, then the tool is useless.
i’m waiting your tests infernal
I have a question. In maya on shading option view we have bounding box point flat shading and bla bla bla. Is possible overide a layer, with script, like point? only full detail and bounding box?
Yes, rvInstancer is incredibly slow but I fail to see where its bottleneck is.
Instancing by particles manually for me is very fast on 2012.
Thank you
Will also try out this new script, thanks for the heads up Infernal!
Dario, sorry to disappoint you but that Meshpaint script is… obnoxiously unusable. The instructions made no sense, and while I see what the author was trying to do, I was unable to get any instancing to happen at all. It was unintuitive and made no sense and appeared to do nothing that spPaint3d and Scatter already do. Try it if you like, and perhaps you’ll have better results, but I spent an hour with it and got nowhere. Painted my vertex map and everything, and it still sucked.
I’ll try regular particle instancing in the morning; at least I already know how to control particles with a map!
“Regular Particle Instancing” is super quick. I just can’t get more than one instance too show up… 
Tried this and still only one instance showed up:
paricleShape1.randIndexPP = rand(0,5.9) ;
Perhaps it’s a vray limitation I’m not sure but if I get it working it’ll be choice of “flooding” geometry with instancing.
In your ‘particleShape’ node, under the ‘General Options’ sub menu, did you select ‘Particle ID’ under the ‘Object Index’ pull down menu? By default it’s set to ‘None’ which means only the very first object listed in the ‘Instanced Objects’ list of the ‘Instancer’ node will be used.
Set it to ‘Particle ID’ instead.
Also make sure that the ‘Cycle’ option in the ‘Instancer’ node is set to ‘None’ instead of ‘Sequential’. This should utilize all objects in the list. You don’t even need to use an expression, but it is recommended as it will allow you to create a much more appealing object selection randomness.
did u try it?
is this tool better then the spaint3D witch the best tool i found so far
Originally Posted by SreckoM
[i]I am not sure if this was mentioned before.Link[/i]
Thanks for the heads-up. It looks good, doesn’t do anything rvInstancer or scScatter don’t also do, but not a bad script. My only beef is a wicked memory leak, running Win7 x64 and Maya 2009. RAM shot from under 1GB in my scene to the full 8GB being used… Crashed my new workstation for the first time since I built it, a month ago! Had to happen sooner or later, I guess!
It’s good, I like the focus on even distribution but the problem remains that it has to be a grid-based evenly tessellated mesh as it relies on vertices as its method of distribution. If it somehow could “project” it’s own distribution grid onto a surface this tool would rule!
I agree, it’s on there in 2012 - first time I completely crashed a x64 12gb system :eek: