How do I cover an object with a population?

[reck]

Just been playing with the new release.

I've added a displaced Octahedron object and then loaded in a population of grass and anchored it to the Octahedron object. I'm only seeing the top half of the object covered, how do I get the whole thing covered?

[yossam]

I think you have to make 2 populations and rotate the other to cover the bottom. How did you displace the Octahedron?

[reck]

Ah yes I can add a second pop and rotate, seems to work fine.

Is there a more accurate way to control how high or low a population climbs/falls over the object? For instance if I want the population to start at the bottom and then climb up say 10 metres, or 40% of the object, how do I do that?

With the terrain I can do this with a distribution shader to get exact control over the max and min altitude along with a fuzzy zone. Maybe I can do the same thing with objects but i'm not sure this is the case?

Yossam, the object was just displaced with a couple of power fractals.

[yossam]

I would try the distribution shader..............

[Oshyan]

Populations are "projected" away from - perpendicular to - the plane that defines the population area. They only populate on anything that is visible to that plane, i.e. the underside of objects are not populated, unless you flip the population over and project from the bottom. There is no way to control "how high" it goes within the population node just as there's no "height" or "slope" control natively in the population; the restriction is a basic limitation of how the populator currently works (we'll work on 360 degree populating for the future). To restrict populations of any kind you would continue to use the Mask input. You could indeed try a Distribution Shader...

- Oshyan

[Dune]

Or a distance shader with an extra camera somewhere in, or on top of, or under the rock. That way you can distribute sideways (east-west, e.g) as well.

[reck]

So looking at the sphere below, if I wanted to raise the grass to the level of the red line I would add a second population, flip it 180 and use a distribution (or distance) shader to prevent the population from reaching the top of the sphere?

So basically if you want a population to pass the centre point of an object you need two populations?

[Oshyan]

Yes, or project from the side if you don't need to see the back side. Remember, you can project at any angle (by rotating the Populator), but it will always be limited to planar projection for now.

- Oshyan

[reck]

Yep seems to work well, thanks. Just wanted to make sure I was doing it the "correct" way.

[icarus51]

Just been playing with the new release.

I've added a displaced Octahedron object and then loaded in a population of grass and anchored it to the Octahedron object. I'm only seeing the top half of the object covered, how do I get the whole thing covered?

Help! I don't manage to "sit on objects". I tried several times but nothing. I load an object (i.e. sphere), i load population (i.e. grass clump), i check the button "sit on object" (Sphere 01) but the grass don't sit on object, it don't appears. What's the problem? Is it my fault or what?
Thanks for hints.

[Dune]

Is the population centered on the object location?

Here's a quick setup.

[icarus51]

Thanks Dune,
But i don't understand where is my fault. I have done more or less the same things that you have done ... i will have better studying.
For object location do you mean the vertical of sphere on the ground?
Greetings.

[icarus51]

This is my proof:

Where is the error?

[attach=1]

[kaedorg]

This is my proof:

Where is the error?

[attach=1]

On grass clump object, rotation tab
you need to check "Lean to terrain/object normal"
don't lean = 0
reduce lean = 0

this will put the grass on the top half of the sphere

Hope it helps

David

[icarus51]

Hi David,
Unfortunately not even this works.    This is a big mistery, a puzzle for me. There is something wrong but i don't understand where is the fault. For tonight is enough... i will try again tomorrow.
Thanks for reply.