Hi

I have a problem with ecosystem tree population. I have a forest and a trail running in the middle. The terrain has a mixed material of an ecosystem forest and a rock for the trail. After population I can't avoid having some trees growing on the trail material, and even in the surrounding water.
How can I avoid this?

thanks

leo

I'm really a lightwave user who just got vue as part of my upgrade, but I did see a few things on this while messing around....  I think what might be simple enough is to use a temporary box on your path.  Vue has a density contol that has reference to "Foreign object"  in other words just dropping box to sit on the path, then press populate... Vue will not place any trees near the box.

Alternately I noticed that a grey scale image can be used to control population. I suppose if you render an overhead shot of the unpopulated ground surface, and then convert the image to black and white (invert if necessary) tress should not grow on blank areas 

Leo,
Post a screenshot of your material settings - especially the function editor so I can get an idea of how you are creating your path. 

Talley, I like the idea of the dummy box ... you can then select the box (or a series of boxes), Leo, and then hide them from the render.  Put them on their own layer and turn the layer off so you don't even see them any longer.  That's the way around creating the density map... but I use density maps to create trails.

Also make sure you check 'do not populate below foreign object'... or something like that in the ecosystem density tab.
Also choose '100%' sampling quality.

Thanks for your replies - I posted a screenshot of my material.

In the meantime I think I figured out something. The smaller the populating objects are, the less they will invade the forbidden space. I think it has to do with how Vue treats their geometric bounding box. It seems that the ecosystem allows objects to show beyond their defined area, as long as part of them is still inside.

I can't think of a way to tell Vue that the whole object should stay inside the defined area.

Talley - the foreign object idea sounds like a smart workaround, I'll try that later.

Leo.

Here you can see that the population aligns nicely on the sides of the path, when using small trees (or any other object - it doesn't matter).

Well, for spreading out items the center of the object is used. So no wonder that the smaller the objects are the higher the chance is that it is ok.

In your case the major thing is the filter you have used. Make it more steap and it will work.

I post a screenshot i did a while ago. don't be worried about the german words, it was for a german forum. And "Wichtig" means "Important" and "Ergebnis" "result".

One day your ship comes in - but you're at the airport.

Unfortunately changing the filter didn't help. I tried both to density or distribution (or together).

I had this problem once with a grayscale mapped Ecosystem where a road had trees growing on it. Turned out my map was simply too small (in pixel dimensions), compared to my objects.

wow Wabe, thanks for the tip... could be why the 'x' shaped grass patches of my ecosystems always seem to invade my streets and curbs slightly.

Jim, you too have a point, VUE seems to be sensitive to small images... trying at least a 1024x1024 map may help Leo??!

and - I see you have 'populate below foreign object' checked, did you try unchecking this? (must if you use Talley's suggestion)

Also, did you try changing the slider for 'smooth blending strip' closer to 0 instead of 100?  Not sure exactly what this does, but I have a theory, and wanted to see if it works... maybe vue is 'blurring' your trail for you with this, and you don't want it blurring that line?

 

Try this link..theres a few video tutes that might help..slightly different technique but greater control over the eco systems.

http://forums.cgsociety.org/showthread.php?t=369883

FuzzyVision- I tried all the techniques above but nothing helped..

IvanB - Thanks alot , that seems like a great way to get around this problem! I will try that later.

Leo.