PDA

View Full Version : Upper limits on importing dense objects?


lapdog
06-10-2005, 12:37 AM
***Note***
While my predicaments is specific to importing polygon objects and meshes from Maya into Vue, I would like to hear about your experiences of importing dense objects from other programs such as Lightwave, 3DSMax, etc into Vue
***End Note***

I created an untextured polygon bridge in Maya with 9K vertices and export from Maya to an Alias/Wavefront obj/mtl set of files. This imports quickly and easily into Vue.

I created a Maya paint effects oak tree, converted to polygon mesh, converted to simple file textures (instead of Maya shaders). The final object has around 30K vertices. When I import into Vue, the program hangs with 100% CPU utilization and it take quite a while to regain control of my WinXP workstation, i.e., it takes 20 minutes to terminate Vue. The workstation has 1.2gb memory.

I exported a terrain from Vue to Maya with 4K vertices, refined the surface to 40K vertices and exported to obj/mtl. When importing the refined untextured terrain into Vue, Vue again hung (or apparently hung as it never completes).

My questions then:

1. When Vue hangs during import, is this because there is some upper limit on polygon mesh size or is it because of some other reason? I could keep testing this but everytime Vue hangs, its another 20 minutes of my life down the drain (sorry to whine).

2. Is there another way to export from Maya to Vue besides obj/mtl?

In any case, if you are successfully importing dense meshes into Vue from other programs, I would love to hear about it. If you are importing dense meshes from Maya, then I would really love to hear how it worked for you.

Cheers!

lapdog
06-10-2005, 12:47 AM
Forgot to mention that importing the terrain with 4K vertices into Maya and then exporting out to Vue without modificaion works fine.

Also not sure if Vue is gobbling up memory (and this causing disk swapping) when the import fails with 100% CPU utilization. It takes about 5 minutes to get task manager up, and memory seem adequate, but I could be misreading the stats.

Wabe
06-10-2005, 07:39 AM
I had always the impression that Vue especially struggles with objects that contain small and many polygons - trees for example. With leaves and small branches.

I had cases where the import took much longer - from TreePro - than in other cases where the amount of polygons was similar but differently structured.

Reminds me to the very old days of FGS 4000. There by importing objects internally a tree structure was created so that each polygon has a relation to the others. Made display incredible fast - shaded real time even in 1985, long time before OpenGL was introduced. BUT, the import was inrtedible slow. We had cases where we waited for days to get it done.

I don't think it is similar in Vue but sometimes the experiences are a little like that.

DorisDay
06-10-2005, 12:09 PM
I recently built a scene with a hand, created in Zbrush 2 (1.5 million polys) Vue took about 30 mins to import the OBJ/MTL file & as soon as I clicked on the Vue interface it crashed & I had to start again, this happened twice...:banghead:

E-on have informed me (after a major rant by me) that they are considering Vue to be able to import displacement maps in future... I wait in hope...

The way I got round this in the end was to have 3 OBJ's with different density meshes, I imported the lowest & placed it, added lights etc, then swapped the OBJ for the next one up using right click > replace by (fit object) > import object, then I repeated again.

It was still very delicate, but at least I got it finished...:)

lapdog
06-10-2005, 10:25 PM
1.5 mill pollys and a 30 minute load - very interesting. I like the replace object feature of Vue and tried the same thing but hung.

After calming down, I realized that 40K vertices is nothing really and on wabe's comments did some simple experiments involving a round trip of a terrain mesh from Vue to Maya and then Vue again.

I exported a terrain from Vue in obj/mtl with a 64K vertex count and imported it into Maya, added a simple blinn texture with high specularity, and sculpted. The same mesh was then exported in obj/mtl and imported into Vue with no problems.

So if I don't smooth or refine the terrain in Maya, I can build the terrain in Vue using photoshop bitmaps, export to Maya with sufficient density for polygon sculpting with a brush in Maya, then export back into Vue for final texturing (hopefully).

As Wabe's suggest, some polygon objects built in Maya are not going to import into Vue. I do wish I could get my polygon tree from Maya into Vue because its gorgeous. Oh well.
Thanks for sharing!

lapdog
06-11-2005, 06:20 PM
1. I exported a 120K vertex terrain from Vue to Maya (via obj/mtl), pushed some vertices around by sculpting, and then exported the terrain back to Vue. Vue tried to import but hung.

2. I then took the same 120K vertex terrain in Maya and did a polygon reduction down to around 35K, resulting in a lese dense terrain mesh with about the same shape. This mesh imported without incident into Vue for texturing.

3. I took my 35K vertex poly tree and ran the poly cleanup routine (max options) on it, but could not get it to import into Vue - Vue just hung.

Obviously, these simple test don't tell us much except if you really want to do a back and forth object/terrain exchange between Vue and Maya, you just got to keep trying.

lapdog
06-11-2005, 07:54 PM
Using WinXP TaskManager to observe system stats, here is what I see when I import 1) a successful import of a obj/mtl mesh from Maya, and 2) an unsuccessful import of a mesh from Maya.

1. Successful import - I/O reads after loading program around 35K, after importing 35K mesh, I/O reads sitting at around 65K.

2. Unsuccesfull import - I/O reads after loadin gprogram ~ 35K, after attempting to import a slightly modified version of the 35K mesh, I/O reads start jumping into the millions and hundreds of millions if you let it run. There is no increase in I/O read bytes or I/O writes.

Does this suggests that the program is looping during a read of the import file? Maybe.

In any case, I ran (in Maya) a polygon cleanup (minimum options) on the 35K mesh that failed to import into VUE. This then imported into a fresh scene in Vue, was saved as an .vob object (vue object), and imported into my synchronized Vue scene. Success of a sorts.

lapdog
06-12-2005, 01:33 AM
Got the polygon tree to import from Maya by exporting leaf and trunk VRML2 data sets that can be imported into Vue. No textures came over, and trying to texture the leaves by hand using file textures from Maya (color, transparency, specularity) did not work well.

Vue does not support fbx imports or exports yet.

Just more trivia.

lapdog
06-12-2005, 06:35 AM
Made one last effort for exporting the polygon tree with textures from Maya into Vue. Exported the tree as FBX from Maya, opened up 3DSMax7, and imported the FBX - looks great (see note below).

However exporting the tree from 3DSMax7 to Vue using .3ds or .obj formats did not work very well. Vue reported an error reading the .obj. Vue imported the .3ds mesh but without textures. VRML export from 3DSMax7 into Vue worked but no textures.

Seems Vue needs to read and write FBX!

note: in order for 3dsMax7 to read a Maya FBX file, you need to download the new Alias FBX plugins for 3DSMax7 (Alias bought out Kaydara). Remove the old plugins and install the new - look for Alias (fbx) in the export list.

That's it.

paladin6303
06-12-2005, 09:59 PM
Just tried a LW import of an early build of a 48k poly starship I created import time, about 8 seconds, tried it with the final build of 68k polys and vue crashed. Quick test, and maybe something with the second file itself.

I'll try again later, just taking a break from working outside, it's really too nice to be behind a monitor today.

DorisDay
06-13-2005, 12:33 PM
Must be nice to see the Sun occasionally huh...:)

CGTalk Moderation
06-13-2005, 12:33 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.