space dome addon

[cyber_space_doc]

I think scaled and unlit textured point sprites would be optimal for the leaves, however I am not sure if the the leaf texture would show up instead of a green dot...

[eburacum45]

Here's a little forest of alien balloon trees I've just placed on the planet Trees in OA.
Anders Sandberg named this planet after the dominant lifeform...



You are right, this slows the program right down, even though there is only one model.

How do they do it in Ogre, I wonder?

[Fenerit]

While the number of different models affects the size of the Addon and memory usage, the total number of models that is drawn affects runtime performance. 100x the same model is just as bad for performance as 100 different models, although it uses a lot less memory. (I'm assuming the different models all have the same complexity.)

Consider that a single "decent-good looking" tree, minimum requires over 30K polygons!

[selden]

My vague understanding is that such things are usually implemented in games by using "billboards", not not with full 3D models.

What that really means in terms of an implementation in Celestia, I'm not sure. 1 point sprite/tree, perhaps?

[Fenerit]

Perhaps one trunk and one sprite, one trunk and one sprite and so on...

[LordFerret]

My vague understanding is that such things are usually implemented in games by using "billboards", not not with full 3D models.

What that really means in terms of an implementation in Celestia, I'm not sure. 1 point sprite/tree, perhaps?

What if your forest were of billboards, much in the manner of that Globular Clusters 3D addon by tirooly? Then you could use an actual image of 'forest' of any type. An 'above' image could be utilized for looking-down-upon views as well. Yes?

[rthorvald]

What if your forest were of billboards

In some cases one could use something like that - like Seldens 3D-billboards inside a sphere. But it won??t work in a 3D environment meant to be explored.

- rthorvald

[Fenerit]

For the billboards method I have found this:

http://www.hortus3d.com/fr_page_frame.htm

(look at "techniques 3d" button)

EDIT LATER:

Instead, for a more fruit and not-woody free Win program:

http://www.kurtz-fernhout.com/PlantStudio/screens.htm

(see Order for the serial)

[Chuft-Captain]

I am particularly interested in the view inside Thorvald's rotating cylindrical habitats; they look extraordinarily good. A nice rotating habitat surrounded by a few tens of metres of rock should be safe from almost all radiation.

I wasn't aware that Runar had done cylindrical habs...where can these be found? Maybe you can post some pics Runar??

Runar, what's the radius of your Bernal Sphere? It looks to be fairly true to the original O'Neill design.

PS. The Island One design was on my TODO list, but after seeing your effort, I think I can cross that one off.

[rthorvald]

where can these be found? Maybe you can post some pics Runar??

They can??t be found anywhere yet, they will be in Ran III. But here are some screenshots:

(click for full-size):












The hub rotates; the embedded mirrors too, and if you look closely, they actually reflect the landscape inside.

I haven??t filled it with buildings because of the poly count - as i have other structures with complex architecture elsewhere, i found it neccecary to economize. But there is a generic landscape with some mountains and lakes.

Runar, what's the radius of your Bernal Sphere? It looks to be fairly true to the original O'Neill design.

It is rather big, 9 kilometers.

PS. The Island One design was on my TODO list, but after seeing your effort, I think I can cross that one off

Why? Put it back on the list, and we??ll have more...

- rthorvald

[eburacum45]

From Fenerit's link
http://www.hortus3d.com/fr_bil.htm
I note that these architectural programs use dynamic billboards which rotate to face the 'camera'. The tree always looks face on to the camera in that case. Can this be done with sprites?

(incidentally where do we get the version of Celestia which has sprites enabled as described in this thread?)

I have also been looking into Microsoft Train Sim, which has some nice trees on two or three intersecting billboards (nonrotating)- this technique works well for fir trees in particular.

[selden]

Celestia v1.5.0pre3 (and current cvs) supports the new CMOD point-sprites. You also need graphics hardware that supports OpenGL v2.
I think Chris is hoping to make comparable software sprites available for the other render paths, but that hasn't happened yet.

http://www.celestiaproject.net/~claurel/celest ... .0pre3.exe

Steve Binder is providing a copy of pre3 for Macs on his Web site at
http://stevenbinder.net/

[Fenerit]

Another free open source program for making trees and plants (with the support of LUA):

http://ngplant.sourceforge.net/