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Manveer Dhillon
09-25-2016, 11:32 AM
Hi guys, I'm trying to make a movie theater in Lightwave 2015. I'm not quite sure how to project or add a movie file to play from the movie screen. Any ideas would be really appreciated. I'd also like to create a beam of light effect from the projector to the movie screen to create the illusion that the movie is actually being projected. :) Thank you.

jeric_synergy
09-25-2016, 11:58 AM
Several ways:

1) To get the screen, you just need to texture map an Image Sequence onto a polygon. This is identical to mapping a single image onto a polygon, but you've selected the first in the sequence, and told LW that it's a sequence in the Image Editor.

You'll almost certainly want to get your "movie" into individual frames, as this will help you avoid a raft of headaches dealing with animation formats. Just trust me on this one.

2) To get the projector bit, you can also map your Image Sequence onto a SPOTLIGHT. (Some light types support this, some do not.)
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This can be a single image or a sequence. The advantage here is the projection comes from the light, so objects can move thru it.

IIRC, you can turn on VOLUMETRIC and see the image along the axis of the light, SORTA. As ever, set up the simplest possible setup to test this. I predict LOTS of fiddling to get it 'right'.

If memory serves, a fairly random projection image is just as convincing as the real thing, and might render considerably faster. So you may find it good to put one sequence on the screen, and use another as the projector effect.

Good luck. TEST FIRST, in the simplest possible way. Save yourself frustration.

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BTW, volumetric rendering slows down the render A LOT. Another (cheesy) way to get the projector effect is to have multiple cones with Edge Transparency cranked and quite a bit of Opacity removed. They can flicker and move about, and will render much faster than an actual volumetric light.

Be sure to have a look at actual "projector light" to quantify what you are trying to get-- your idea of what it is, and what it actually is, may be quite different.

js33
09-25-2016, 04:16 PM
If your camera is not moving in the scene I would just make your movie screen a 100% Blue or Green surface then add your movie to the screen in a compositor with a keying plugin. After Effects has these plugins built in. If your camera is moving in the scene you could still do it this way but you would have use camera tracking plugin. Also you could easily add a light projection effect in AE using the Trapcode Shine plugin or others.

So bottom line if you don't need to move the camera I would do it in AE. If you do need to move the camera it may be easier to do it in LW. Of course doing it in post will be a lot faster than doing it in LW and you will have a lot more control over the final look.

MonroePoteet
09-25-2016, 05:32 PM
Here's a sample scene using the techniques Jeric describes. I used a rectangular mask on the Spotlight Image to have the Volumetric Light fit the screen, then used the Volumetric Light's Texture using the same MPG file as is mapped to the Screen rectangle (with 100% luminosity and a flickering Checkerboard to make it look "filmy"). Although I used an MPG movie as the projection / texture image, I tend to agree with Jeric and usually use framestores (individual files per frame).

Good luck!

mTp

jeric_synergy
09-25-2016, 06:57 PM
If your camera is not moving in the scene I would just make your movie screen a 100% Blue or Green surface then add your movie to the screen in a compositor with a keying plugin. After Effects has these plugins built in. If your camera is moving in the scene you could still do it this way but you would have use camera tracking plugin. Also you could easily add a light projection effect in AE using the Trapcode Shine plugin or others.

So bottom line if you don't need to move the camera I would do it in AE. If you do need to move the camera it may be easier to do it in LW. Of course doing it in post will be a lot faster than doing it in LW and you will have a lot more control over the final look.
Actually, what js33 said, but even if you ARE moving your camera it will be pretty easy. Besides AE's matching tools, there are interchange facilities between AE and LW that are a good thing to know.

js33
09-25-2016, 11:39 PM
Yeah that's true you can just send your LW camera to AE if you need to match.

jeric_synergy
09-26-2016, 12:03 AM
Better than matching when the angles become acute.

squarewulf
09-26-2016, 02:06 AM
You can do it several ways. I definitely would try to stay away from using any chroma key efforts. If you absolutely need a matte then render out a separate pass for your screen and use that for a luma/alpha matte.

For the screen I would simply apply the video as a texture to the screen in the diffuse and luminosity channel. Then you can turn on raytracing and the screen will illuminate your theater properly.

Then check out video copilot volume light rays tutorial
https://www.youtube.com/watch?v=frXQxwMKh6c

Alternatively you could render out your theater with no texture on the screen. Drop a null object the 4 corners of your screen and send them into AE, then in after effects use this 3d corner pin expression (http://www.motionscript.com/design-guide/threeD-corner-pin.html) to pin your projected image onto the screen. Then render out any alpha channels you may need for objects coming between you and the camera. And of course then use video-copilots volume light trick.

js33
09-26-2016, 03:06 AM
You could make a separate pass for an alpha channel but blue or green screen will be just as clean. Hollywood does it all the time.

Just set the screen to R-0, G-255, B-0 with luminous at 100% and everything else at 0% then just key it out in AE. It will be just as good as a second pass alpha channel.

jeric_synergy
09-26-2016, 09:18 AM
Since we're entirely within the digital domain, green screening is unnecessary: corner pinning is plenty, but of course actual data exchange between the two apps is better.

Like we said, there's multiple ways of doing this.

Manveer Dhillon
09-26-2016, 09:57 AM
Thank you very much for all the tips guys. I forgot to mention one small detail... My scene will be imported into Unity to play with the HTC Vive. My apologies for that. I will give all methodologies a try starting with Jeric. Maybe this can be done in Unity also, I'll do some more research.

ernpchan
09-26-2016, 10:25 AM
You probably need to apply your footage via a UV map then.

squarewulf
09-26-2016, 02:21 PM
You could make a separate pass for an alpha channel but blue or green screen will be just as clean. Hollywood does it all the time.

Just set the screen to R-0, G-255, B-0 with luminous at 100% and everything else at 0% then just key it out in AE. It will be just as good as a second pass alpha channel.

I don't know if i believe that. Why on earth would you do that? There are easier more superior methods available since its all digital. Also not to mention if you have any GI or reflections you will then have to deal with spill and garbage masking like you would a real green screen. Just set the surface of the screen to be a matte object, done. No additional steps required and your results will be perfect.

js33
09-26-2016, 02:29 PM
Yeah I agree the matte object is the better option. It's just I had an issue recently with transparency with an alpha channel and I used a blue screen background and it worked great so I just threw that out as another option. But the better solution in my case was to set the Alpha channel surface under Advanced to constant value of 255 rather than Surface opacity.

erikals
09-26-2016, 05:40 PM
MonroePoteet, neat :)

thanks.

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jeric_synergy
09-26-2016, 06:11 PM
You probably need to apply your footage via a UV map then.

I suspect you are correct. OP, don't worry about this: UV'ing a rectangle is probable THE simplest UV mapping possible.