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View Full Version : Any Info on creating Point Cloud Data sets from LW?



Dexter2999
07-31-2010, 02:53 PM
Hey,

Just re-watched an episode of fxguidetv. This one was about using Nuke in the post production of District 9 (I think it was episode 55). Anyway, it was mostly about compositing in Nuke but it demonstrated a method of bringing in a Point cloud generated from Maya (I believe) and applying the color information to the point cloud. They were able to leave out the specular channels and relight the image inside Nuke. I was interested if LW and Fusion could be used similarly.

There was also a neat trick of mapping the color information to a histogram made like a point cloud to use for color matching compositions. Not exactly sure what went on with that but seemed kinda neat.

I like the fxguide/fxphd stuff but it pretty much seems slanted to Maya/Nuke. Still no reason to not take note of the approaches to see how they could be adapted to LW/Fusion.

Anyone here have experience/info on point clouds in LW?

Dexter2999
01-07-2011, 10:25 PM
BUMP

Yet another episode of FXGUIDETV where they mention point clouds. This time in relation to stereoscopic Cut and Paste (if I understood correctly).

Anyone here have info on this technique? I don't see much info for outputing them in Google. Most seems to pertain to importing scan data to create models.

I caught on mention that seems to indicate that this process is vertice info from your model exported as FBX? Does this sound right. The point clouds in the demo's I have seen seem VERY dense. What would you do to accomplish this? Bump the sub-D level way up then bake all animation into the vertices? Then save out as FBX?

Am I even close?

Someone? Help? Please?

Titus
01-07-2011, 11:48 PM
If the pointcloud format you mention is .ply (found a reference in google), it's very easy to implement an exporter in LW. Not sure how this can work in Fusion.

Dexter2999
01-08-2011, 12:16 AM
If the pointcloud format you mention is .ply (found a reference in google), it's very easy to implement an exporter in LW. Not sure how this can work in Fusion.

Thanks for the reply, Titus. I found a reference in a tutorial video that refers to importing point cloud data from boujou and PFtrack. So apparently it can be used in Fusion. Not that I have a use for this technique. But I am seeing increased references to it's use. I really like LW and dont want to see it fall behind (any further).

Mr Rid
01-08-2011, 07:12 PM
A compositor friend at Sony uses point clouds from Maya to do lighting in Nuke. Fusion has a 'Pointcloud 3D' import, that I assume would load lidar or Pointtools data.

How Pixar uses point clouds to bypass ray tracing and GI-
http://features.cgsociety.org/story_custom.php?story_id=5615

'Roto' modeling from a point cloud-
http://www.youtube.com/watch?v=QL3cAgCuLDA&feature=player_embedded

Using Kinect for point clouds-
http://www.youtube.com/watch?v=yZSXXFwsyhc

iPhone app for making quick scans-
http://www.youtube.com/watch?v=IEZtiDrxh-E&list=PL616D48BC0FF37D7E&index=17

I dont know what is going on here using Pointtools http://www.pointools.com/ and LW-
http://www.pointools.com/forum/viewtopic.php?f=16&t=25

Dexter2999
01-08-2011, 08:52 PM
Thanks for the links.

I think I see why no one talks about it here on the boards. The Pointools software is well outside the means of most of the users here. The applications I have seen are all on features and I think (being honest) LW is not the market leader there.

This isn't the area where hobbiests or logo guys like me really "play". Out of my league as it were.

Netvudu
01-08-2011, 10:57 PM
yeah, this is quite common in Houdini as well, but you know, the tools are there already. You donīt have to do much. I wouldnīt dare trying this in LW unless a exporter was previously created by someone.

archijam
01-09-2011, 01:17 PM
I am also curious about this.

That District 9 video also used a lot of in house plugins, so it was not really clear if nuke could do the point cloud stuff out of the box ..

I had not heard of pointtools for lightwave .. i have met Faraz - will ahve to ask him for more details.

We use pointtools for rhino, but other than adding pointcloud models to the scene it frankly doesn't do SO much. If oyu want to have full use of the points you first convert them back to rhino points .. not very efficient. That said, it's great in some cases.

dex - a lot of pointcloud data is not much more complicated than (per point) 3 coordinates + a rgb value + grayscale reflectivity value (the last two in the case of terrestrial laserscan data).

Dexter2999
01-09-2011, 01:23 PM
Yeah, but they are using point clouds generated from Z depth matts then mapping projected RGB values to recreate models.

I think the gist of one of the recent articles was in how to use this technique to cheat a 3D effect. And I am not certain but I think there were issues with cut and paste with 3D because you could use this to relight and relocate your elements.

Just seemed very interesting development. And I was concerned because I haven't heard anything about it in the community.

archijam
01-09-2011, 01:47 PM
Yes this point cloud thing has suddenly become the hot topic.
The laser scan data has been around for almost 20 years but people are finally getting an idea of what they can do with it ...