Page 1 of 3

Spooky Island

PostPosted: Sun Jul 06, 2008 4:59 am
by Jonnee
One more time I need your help, friends:

Something happens that I don't understand. Today I created some trees. They do really look good, but some objects of my island disappear now when the camera rotates to a special point. *spooky* :o I don't have an idea why it happens.

Some pics for your understanding:

Image
^^That's the island with all visible objects

Image
^^Suddenly the tree trunks, some leafs, bushes and the stones in the background are invisible. And I can see the pavement far away behind the corner of the canyon.

Anyone can help me? Is there a button in blender that I forgot to press or a value to set?
The trunks and stones are simple uv-mapped pics, the leafs and bushes are .png (useAlpha is set).

Thanks. 8-)

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 11:07 am
by Nadnerb
Okay, that's kinda freaky. Does plasma have something against tree trunks? Because the exact same thing is happening to my age. I suspect it is because of some sort of total object rendering limit, because it happens when I face the busiest portion of the age... but why all the tree trunks first? :P

(unfortunately for you, this post means I can't help you.)

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 11:11 am
by Robert The Rebuilder
Welcome back, Jonnee! It has been a long time.

I'm not sure exactly how Plasma culls its objects from the scene, but it might be related to the origin of the object and its bounding box. One possibility for the disappearances might be that the origin of the tree trunks is not located within the object. For example, if you had made a tree, then (in edit mode) shifted its polygons over, that would keep the origin in the same place.

So, check that the origin of the trees are located in the center. If not, it is easy to correct:

- Select the object
- Make sure you are in object mode
- On the Editing panel (F9), click "Center New" to shift the origin to the center of the object

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 11:18 am
by Nadnerb
Okay, I went and took some pictures of this phenomenon, and it supports my theory for a max object, (or perhaps max span) rendering limit. First, as these are linked objects all their object centers are located at their center. Second, they vanish while facing the center of the age, where all the stuff is. Third, only entire objects or discrete sections of objects will vanish.
Image
Image
Unfortunately (or not :D) the tree trunk theory is debunked here. I loose a lot of grass, and a few entire trees. :P

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 11:30 am
by andylegate
See, now THAT is something that happens in Zephyr Cove, once you get down the beach, and then turn around and start back, where 90% of the Age is being rendered. The trunks stay for me, but my palm fronds will wink out of existance......unless I turn and look around, then they'll pop back in.

Now the centers of the palm fronds I just discovered were not centered.

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 2:18 pm
by Jonnee
Thank you for the welcome, Robert. It feels good to be back. 8-)

Nadnerb's theory of a max amount of identic objects seems to be the right one.
I tried the "center new"-thing, but nothing happend. But when I deleted all trees and kept only one the grafic error did not happen again.
After that I copied the tree and its leafes six times. That was too much for the game engime. Uru crashed at first and in the second try different objects disappeared again.
Tomorrow I will create new trees with different object names and will copy them only three times for example. I think it should work.

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 10:18 pm
by Grogyan
I'm just guessing here, but could you add another layer for those foreground objects just like the transparencies?

Looks to me like a z buffering issue, not a max object limit

Re: Spooky Island

PostPosted: Sun Jul 06, 2008 11:56 pm
by Nadnerb
This is not what a z sorting error looks like. The foreground objects are not being drawn. Otherwise they would at appear, and perhaps interfere with things behind them, but not vanish entirely.

Re: Spooky Island

PostPosted: Mon Jul 07, 2008 4:44 pm
by Paradox
Binary Space Tree? plSpaceTree is still lacking in DrawableSpans.

Re: Spooky Island

PostPosted: Tue Jul 08, 2008 4:37 am
by Robert The Rebuilder
Do you know whether Plasma automatically generates BSP trees if it doesn't find them in the spans, Paradox? Or does it use the object's bounding boxes for culling?