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NSF
10-08-2010, 04:48 AM
So I downloaded some fairly polygon heavy models of coral and i then got a bit fancy (by my standards) and i used PF to scatter elements within the group over a plane that I'd mapped with a radial gradient ramp. So I have a nice distribution that's circular and avoids the centre like i wanted. The problem comes at render time though. My bounding boxes are visible everywhere, the geometry is visible in the viewport but I hit render and less than half shows up. What's the go here?

Any thoughts?

Is there a limit to the poly count of geometry that PF can scatter? Although that wouldn't be it because it is scattering just not rendering out, even with BSP2 on mental ray.

HornBerger
10-08-2010, 06:56 AM
Select your particle flow source and go into the modify panel and make sure the following settings are set correctly (especially viewport and render percentage to 100%)

Is there a limit to the poly count of geometry that PF can scatter?
yes, you can restrict the number of particles in your flow to the "upper limit particle amount" setting

[image showing important pflow settings, right click and select view image to expand]
http://img819.imageshack.us/img819/108/settingsf.jpg

cheers! :)

NSF
10-11-2010, 12:40 AM
Thanks for the screenshots hornberger but it doesn't appear to be that which is the problem.


I don't have that many particles that I am emitting, 800 or so and they are stagnant, not moving. I just use PF to scatter some geometry around.

I just don't get it though, the bounding boxes are there, the geometry just doesn't render. I went and rendered the original group and all of those pieces render fine, so not a material or back facing issue.

Any further suggestions?

NSF
10-11-2010, 01:17 AM
So I decided to delve in to some of the other settings and see what I could turn up. Fortunately, I made some progress right at the outset.


In my PF source I have the default entry of Render 001 (Geometry) and I have 100% visible (phew) but when I change the render result from Single Mesh to Mesh Per Particle I then get geometry in every bounding box!

Great! All the particles are rendering in place BUT and this is the bit I can't figure my way around...the particles are now just ONE of the meshes inside my group, they aren't different members of the group like before.

So am I running into some kind of polygon limitation for the Single Mesh? How do I work around this?

JohnnyRandom
10-11-2010, 06:34 AM
Particle Per Mesh should solve the issue for sure. That is odd that it only displays one member of the group. Did you inadvertently switch the Shape Instance object or untick Group Members?

If you happen to have multiple events try enabling Acquire Current Shape too.

As far as I know there isn't a poly limit on the objects, there may be, I haven't ever run into that, not to say it doesn't exist but I have used quite a few faces per object before. Upwards of 30,000 faces w/ around 1000 particles without issue not huge but moderately heavy.

floopyb
10-11-2010, 06:37 AM
you can try the workflow described here:
http://forums.cgsociety.org/showthread.php?t=763017
You may need to collapse the whole thing into one giant mesh before you try to instance replace the baked particles if you are using groups.

NSF
10-11-2010, 07:58 AM
I don't think I need to bake anything, I'm just scattering static particles about the place. They don't need to move, the surface they are on doesn't move.

It's odd, even when I choose 'mesh per particle' the bounding boxes all stay the same sizes, but on rendering I only get the one object from the group, not various group members.

I've uploaded the file and i'm sorry it's so massive but I am using the some poly heavy geometry (which is excessive for this level of detail I know). Apparently it's 55498 Vertices, that's what I get in the Shape Instance rollout.

If you could try it and see if you have the same issue, either only some geometry rendering despite it showing everywhere in the viewport OR just identical geometry rendering once you select 'mesh per particle' then it'd be a huge help.

Cheers,

edit: http://www.megaupload.com/?d=CHLLEM9J

floopyb
10-11-2010, 09:15 AM
You just want to bake to helpers and chose the frame range to be 0-0 so it only keyframes 1 frame. Once you have your points you can use Modifiers Zorb's replace Instance function to replace all the points with the object of your choice, in your case a collapsed version of your large mesh.

NSF
10-11-2010, 10:51 AM
Thanks floopy but that just spurs me to ask more questions...

Is that plugin/script compatible with 2011?

And when you say collapsed mesh do you mean I need to attach all the elements of the group together into one mesh object?

floopyb
10-11-2010, 10:56 AM
It should be, but I dont use 2011 so it may do some weird things.

You will need to collapse it so there is only one object that you can replace the points with. Either that or you can make copies by hand and align them to the points.

NSF
10-12-2010, 04:06 AM
Floopy: I've got your script and I've run it and now i have a number of tabs with various lists of scene components...


I select my PF Source in the Base Objects tab but even with right click I don't see the relevant thing to choose to do the replacement.

What is it I am looking for?

I just thought, if only scatter would work with proxies, oh and if i could add multiple objects in to be scattered together.

It's such a shame the PF way failed. Maybe I can have a crack at minimising my base geometry to scatter.

Cheers,

Trying 8 things at once.

floopyb
10-12-2010, 04:23 AM
You can use vray/mr proxies with my method.
Once you have baked all of the particles to points, select all the points, run the Modifier Zorb script, make sure "selected" is checked and go to the "base objects" tab. Right click on the "point" entry and choose "Make object instances". You should get a dialog where you can select your VrayProxy/Mesh object. Done!

You can then select the "vrayproxy" in the "base object" tab and press "Get Base Object Properties" to mass edit/ randomize all the vrayproxy settings (you may have to deinstance them first!)

NSF
10-12-2010, 05:29 AM
Ok well progress and then *sigh* hurdle.

So I got the Pflow bake script and got that working, I end up with points. Then when I select objects via your script floopy it tells me that i have 806 helpers selected, so I deselect the 6 I don't want instanced, then I right click the points and 'make object instances', I choose my proxy to instance and then boom, everything in my scene is replaced with MR proxies (1300 odd).

No matter what I do I can't limit it to just working on the points. Maybe this is a 2011 thing.

floopyb
10-12-2010, 05:38 AM
just before you do the 'make object instances' make sure the "selected" radio button is checked in Modifier Zorb, not "All"

NSF
10-12-2010, 05:53 AM
head...meet desk!

NSF
10-12-2010, 06:01 AM
Hmmm well your script is fantastic and i've scattered a singular proxy as a test and come render time...fail. No proxies showing at all.


So I made a test file, arrayed out a few thousand of the same proxy. No worries, they all show.

got-wtf?!

PsychoSilence
10-12-2010, 02:16 PM
Not sure if i'm late to the game here but i released some video tutorials over at evermotion.org dealing with planting and proxy replacing of.

http://vimeo.com/10171617
http://vimeo.com/10342141
on the evermotion website you can grab the maxfiles and scripts as well.

NSF
10-14-2010, 12:52 AM
No PsychoSilence you aren't too late, but you are delayed...where were you last week when I'd torn out less hair?! :P

Really fantastic tutorials. They tought me a lot. I'd been struggling with the grayscale mapping of an object and not showing it in the viewport (I was cloning geometry and making one not renderable) but your method is far more straight forward.

In your second tutorial it's a shame you didn't pause the script working and come back and show the finished product. Also, I could see some value in comparing a forest scattered with non proxy trees and the render time recorded, then do one with the proxy and show the render time improvement.

I'm thoroughly enjoying the use of the multi-sub object material in the Source and it being passed through the life of the particle. I now appreciate the value of the scale operator and the scale entry in the shape instance operator and how they differ.

I'm curious though, in your second tute when you talk about shrubs or mushrooms to generate a wood, how do you do this? Do you duplicate the particle system before running the script?

Is the only variation available rotation? So you need multiple PFs to have different types of trees? Or can you 'tint' a proxies material with a multi-suboject mat? I've got visions in my mind of an overlay or multiply like in photoshop.

PsychoSilence
10-14-2010, 05:18 PM
No PsychoSilence you aren't too late, but you are delayed...where were you last week when I'd torn out less hair?! :P
been busy :D


In your second tutorial it's a shame you didn't pause the script working and come back and show the finished product. Also, I could see some value in comparing a forest scattered with non proxy trees and the render time recorded, then do one with the proxy and show the render time improvement.
I'm curious though, in your second tute when you talk about shrubs or mushrooms to generate a wood, how do you do this? Do you duplicate the particle system before running the script?
On the evermotion website are some renderings i did with the file...
for different types of foliage you set a new variation seed and scale but other then that its the same procedure.


cheers,
Ansi

NSF
10-15-2010, 05:58 AM
But you can't keep different particle systems apart?

It looks as though I'm about to have to prepare some thick foligae, a forest, to be seen from above, from an altitude of at least 100 metres.

So what I imagine doing is scattering a number of MR proxies over the terrain surface.

I've just had an idea though...could I separate the one particle flow out into 3 or 4 via tests?

Let's say I want 10,000 trees and I want to scatter 4 different MR proxies, can I separate the flow into 4 groups of 2,500 and then use that baking script 4 times? I only ask to do it this way because I'd like to use the 'separation' section of the 'position object'. I know trees do clump a bit.

I guess I should also ask for advice regarding realistic looking trees whilst minimising polys.

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