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cirdan
01-21-2009, 02:31 PM
I don't know if there is a "common" name for what I want to do, so I'll explain it as I can...
I want to render in lightwave some animations that are to be projected on non planar surface (for example the corner of a building, or the intersection of two walls in a room).
The problem is to avoid the distortion of the projected image : the render has to be "pre-distorded" (?) to compensate the projection distortion.

If think there must be a smart way to do that inside lightwave, but can't find the right one... Maybe using an object as the camera lense, but which shape should it have ?

Have you guys ever solved this ?
Thanks in advance.

JeffrySG
01-21-2009, 03:15 PM
Sounds like you want to do a 'camera' projection. I'm not sure if LW has this. The problem is that the projected image will need to project differently depending on where the camera is. Hence the 'camera' projection.

This tool might be of assistance though:
ftp://ftp.newtek.com/multimedia/movies/w3dw/Tguide.mov

cirdan
01-21-2009, 03:37 PM
Thanks Jeffry.
I wasn't sure my if explanation was clear, but now I'm sure it was not :-)

The animation is to be projected in "real life", on real objects, not within lightwave.
(Or didn't I get your point ?)

Dexter2999
01-21-2009, 05:53 PM
I think what he was hinting at is that to pre-deform your footage. You need to know where the projector will be situated in reference to position and scale to the building.

You need to copy this in LW (with your camera and the video projected on a proxy object). Then you can deform from there to get a corrected look. To get this to work you will most likely need to use the workflow from the video he linked you to.

Projecting on a corner will present not only keystone issues but could have serious focus issues as well.

JeffrySG
01-21-2009, 11:12 PM
Oh I see now. Yes I did not fully understand you. First like dexter said you will have to deal with focus and keystone issues. You'll need to really figure out the exact space of everything to do that. Also remember that whatever solution you come up with will only look good from a specific area where people are sitting or standing. As they move away from that spot the illusion will go away too. Kind of like those cool chalk paintings you see on the street.

JeffrySG
01-21-2009, 11:17 PM
It might be easier to do any distortions you need in a compositing program like after effects, also.

I would probably start by projecting a grid onto the wall from where people will be sitting. Then take a picture of the grid from where the projector will be. That will show you the distortion that will be needed. It will be tricky.

Dexter2999
01-22-2009, 01:12 AM
Actually I would suggest two projectors that are fed from one video processor using the blending technology they have been working on the past couple of years. Or several projectors in series with a prodouct like
http://www.vistasystems.net/Vista-lp/vistalandingpage.aspx?gclid=CNa43OTcoZgCFQoHswod2y FZnw#
There is another system I can't remember the name of. It's something like SHOWME or SEEME. But you get the idea..

cirdan
01-22-2009, 06:01 AM
To be extremely clear, I want to make something like this (in a few years ?) :
http://www.dailymotion.com/uruk/video/x3iw8q_volkswagen-tiguan-video-projection_events

The work of these people is amazing.
...But I don't get the technology...

Dexter2999
01-22-2009, 01:39 PM
I could be wrong but it looks like they have matched the lighting for some DL2 moving lights (they are projectors inside) and an LED wall.

It is very nice work though.

JeffrySG
01-22-2009, 10:32 PM
yes, that is some kick-a** lighting...

cirdan
01-22-2009, 11:37 PM
Sorry, that wasn't the right example :
here's another one (http://www.youtube.com/watch?v=jOEWRiCwzjo) more clear.

Dexter2999
01-22-2009, 11:58 PM
http://www.easyweb.fr/slideshow.html

They already have a system. You just need to learn to use it.
Why re-invent the wheel?

JeffrySG
01-23-2009, 12:06 AM
http://www.easyweb.fr/slideshow.html

They already have a system. You just need to learn to use it.
Why re-invent the wheel?

That video was much better.... some very cool stuff there.

I really like the little fish on the street.