Vue 5i, Lightwave and DFX composite?

[illusory]

This is probably pretty basic for those of you used to compositing Lightwave scenes with Vue backgrounds -- and probably some of you are experts by now at using the depth merge capabilities of DFX+ in this process.

So I'm looking for anyone who can advise me how to do this. I know how to set up a depth merge in DFX+, with .rla files. Works nicely. But if I want to do this with a LW scene and Vue landscape, I have some confusions...

How can I get the cast shadows from the Lightwave render to appear on the Vue ground? I'll obviously have to render the objects in LW casting shadows on a temporary ground that I don't want to use in the composite. So how to I get rid of the LW ground object in DFX, and have the shadows fall on the Vue ground instead?

Hopefully this is pretty simple but I haven't been able to find the info, and time is pressing down on me...

thanks,
NJ

[dballesg]

Hi NJ,

The first idea that comes to my mind it is that you need to do a two render pass from Lightwave. You normal render, and another one this way.

Put your temporary ground on the scene, but I think your original one would be better becuase you got the shadow integrated, and in the Surface Editor in the Advanced Tab, change the Alpha Channel to Shadow Density for the surface of the temporary ground.

You can activate unseen by camera to your LW objects, you want its shadows, no that they appear on the render. Works with raytraced and shadow maps.

I think it is better use a black background for this unless you are using BCK Radiosity that can affect the colors of your ground.

Do the render, so you get your ground rendered, but in your ALPHA, you get only the shadows. Due you hided your objects they wouldn't appear on the render.

Composite this pass with your normal render using DFX+.

I am not a composite genius, so maybe I am wrong, but I hope it helps.

Best regards,
David

[illusory]

Hi David,
is there a reason I shouldn't do what you say here in a single pass?:

"in the Surface Editor in the Advanced Tab, change the Alpha Channel to Shadow Density for the surface of the temporary ground."

Meaning, could I do that in my full scene render, and then have the proper alpha to composite with the Vue scene's ground?
I thought that advanced tab alpha setting was for using an alpha that already exists, not for producing one. Am I wrong about this? or is there another setting I need to produce the alpha i need in dfx? I'm real confused...

Also, I'm not sure what you mean by "I think your original one would be better becuase you got the shadow integrated". I'm confused because the only grounds involved would be the Vue scene, and the temp one in LW which is just for shadow-catching. When I render in LW i will want to keep the shadow and composite out the ground later.

Thanks much,
NJ

[UnCommonGrafx]

Vue has a LOT of buffers you can export to 'interact' with LW renders.
There are some plugin gems that will get you closer to your goal with a single render. But the R&D for your particular setup may be the biggest hurdle.

THis little gem will get your whole scene over to vue where you can then take advantage of all those buffers when you come back into LW:
http://www.triton.eclipse.co.uk/VueExport.html

From there, within LW, you could use those buffers to properly cast shadows with a foreground composite.
Or, you could try "TB's Vue Image Composer for Vue5 + LW" which, in theory, wouldn't need as many buffers from vue:
http://home.att.ne.jp/omega/tabo/3dlabo/p_lwp.html
(At the very bottom)
This one, though, has had very little conversation brought up about it.
Found it!
Check out this link for the most in-depth conversation I've seen on TB's plugin:
http://www.spinquad.com/forums/showthread.php?t=10971

Spinquad has a whole section of user's sharing how to best get what you have stated you want.

One plug for pay; all others are free.

Or, lastly, you could upgrade to 6 and get that extreme plugin as it's said to be a part of the package with 6.

[illusory]

Thanks Robert for the great resources. Will be very helpful in the long run.
But in the short run...I'm not looking to export my LW scene to Vue, or bring Vue's scene into LW. All I'm really looking for is the way to render my LW scene with the kind of alpha which will allow me to composite out LW's ground, but keep the objects and the shadows cast on the ground, with all the partial transparency. So I can use the Vue-generated landscape and the LW generated objects and shadows, and composite them in DXF+. It seems there should be a straightforward way to do this, but i haven't been able to find it.

I'll go over all those video references on spinquad and see if that info is there. Meanwhile, If you or anyone knows how to export the kind of alpha I'm talking about from LW, please tell.

thanks!
NJ

[hunter]

I did this

http://www.lwg3d.org/upload/wip/2006/04/-11-775487.mov

exaclty as dballesg described. The Corsair and it's shadow were rendered in LW on a shadow density enabled temp ground. Rendered out in 32 bit .tga or .psd or .png.
Then the environment was created and rendered in Vue. Luckily I didn't have anything in front of the Corsair , so no depth channel was required. :) They were then comped together in DFX+.
The shadow density option does exactly what you want , and yes you can render out the whole scene, but the alpha channel will contain only your main object and it's shadow. Or you could use the multipass PSD export to get your shadow, color, diffuse, reflection etc passes and comp in DFX+ as I did here:

http://www.lwg3d.com/upload/wip/2004/07/20-357623.mov

Neither is a stellar example but you get the idea.

[Sekhar]

Another way is to render just the shadows by setting light color to black and shadow color to white. Your render then is a matte that you can combine with a solid shadow color (say black) in your compositing app to generate the shadows.

[illusory]

Thanks, Hunter -- I'll be sinking my teeth into this this week (it sounds like the way for me to go), but I may have to ask you another question or two...starting with...
just where are you enabling shadow density? If it is on the surface attributes advanced tab for the ground, doesn't that have to do with how an existing texture is laid on that surface? How does that CREATE an alpha map?
Or are you doing this somewhere else, like render buffer export? PSD export? rpf?

Your video is great example -- it looks very integrated, like it was done in one app. First time I downloaded it, btw, i got a dinosaur composited with a woman wading in water... :)

Sekhar, does your method give shadows with their gradations of transparency?

[hunter]

Thanks, Hunter -- I'll be sinking my teeth into this this week (it sounds like the way for me to go), but I may have to ask you another question or two...starting with...
just where are you enabling shadow density? If it is on the surface attributes advanced tab for the ground, doesn't that have to do with how an existing texture is laid on that surface? How does that CREATE an alpha map?
Or are you doing this somewhere else, like render buffer export? PSD export? rpf?

Your video is great example -- it looks very integrated, like it was done in one app. First time I downloaded it, btw, i got a dinosaur composited with a woman wading in water... :)

Sekhar, does your method give shadows with their gradations of transparency?

Nope. Shadow density has nothing to do with how the texture is laid on the ground. It simply produces an alpha that contains your object and shadow.
Just create a ball and a groundplane with different textures, position them in layout so the ball casts a shadow on the plane and set the groundplane's shadow density option, render and check out the alpha. you'll see.
And there's 2 seperate videos in my first post. :D

[illusory]

well i'm really loving that dinosaur...and missing the obvious it seems :o

Thanks!

[Ivan_B]

Hi there..Here is a link to a buch of video tutorials i made with regards to vue and LW....It might not be what your after, but I hope it helps...I have had the problem of shadows when compositing vue and Lw..I wanted shadows from the vue envirnment to be cast on my LW object...NO LUCK...Im now getting Xstream for lw. Check out the video called
LW_Vue_6_ Image Sequence_LW.mov

http://www.esnips.com/web/vue2lw-tutes
or
http://md-arts.com/vue/Vue2LW/

If you have any question dont hesitate to ask..
Ivan.

[illusory]

Thanks Ivan, it's great of you to do this...I've downloaded and am watching your video tuts

NJ

[Sekhar]

Sekhar, does your method give shadows with their gradations of transparency?
Yes, and I'll post video clips comparing the two techniques. But for now, check out the really simple scene and PSD setup below to see the gist of the technique.

[illusory]

Ok I will.
thanks!
NJ

[illusory]

OK, i'm having a real confusing problem. I produced a psd file out of lightwave with the shadow density enabled for the ground. worked just fine -- thank you Hunter, i was completely mistaken about that feature!

Meanwhile...back in DFX+...when it loads the psd file, only the shadow part of the alpha is there -- load the same file into Photoshop, and the whole alpha is present! (objects and ground shadow). Save the file out of Photoshop, and THEN DXF shows the full alpha.

This is just bizarre. Anyone know what is happening here? Obviously I can't run hundreds of frames through Photoshop to get them to work in DFX.

Does anyone know of a video or other tut which talks specifically about DXF+ alpha and matte compositing? I've done a number of their tutorials, and they all assume you have an embedded alpha channel or are creating mattes from color values or polygon tools. Nothing addresses having an alpha as a separate file. I've spend quite awhile experimenting and reading the manual, and nothing works here as it indicates. It should be very simple to use a greyscale file to mask areas of the foreground in order to show the background -- extremely basic, yes? But it is not working for me. Considering the above-mentioned psd problem, who knows what is happening...

If anyone could send me a very basic DXF+ file where anything I'm trying to do is WORKING, It'd be a big help...

Any help appreciated,
NJ

[hunter]

There is a movie called PSD Saving here:

ftp://ftp.newtek.com/multimedia/eyeon/

Not speciffically what you want but will help with the use of the PSD in DFX. :)

Theres also some good things about mattes in the DFX coursware which you may still be able to download from eyeon.

[illusory]

Yeah, I have the dfx courseware, and have seen the psd video. That's about importing psd files so you can use layers in the flows. Doesn't help, i'm afraid. Courseware has lots about creating nifty spline masks and extracting masks from color, luminance, etc, but nothing about using a separate image as an alpha. I guess it's supposed to be simple, eh?

Actually, they do go on about how alphas are within the file, and if there is none, dfx will add one (plain). I've tried the tool (matte control) which is supposed to merge another alpha with the one in your image, but the logical settings don't work. So...I've been trying the illogical ones...and everything i can think of but nothing works :bangwall:

[hunter]

Can you post a pic or two of what it is exactly you are trying to achieve? Maybe it'll help.