By dull_slogan_job_eh (195.92.198.75) on Saturday, June 02, 2001 - 07:09 pm:

lightwave RLA and depth of field

the thread "RLA Export on Mac? Alternatives?" discussed lightwave RLA files back in april yet still nothing seems to have been presented to the mac lightwave-using community to allow RLA files to be used

re adams' comments - I've been working with RLA z (depth)_ buffer export to discreet combustion for a month now, and recently to AE5

I can confirm that the problem is the lightwave file and not AE5/combustion's interpretation of the file... incidently I have the zebra-stripe problem encountered by others...

this is a real pain... there is no other way of getting z-buffer information into compositing apps in such a way that it can be used for depth of field (DOF) purposes - although it is possible to generate an 8-bit z-buffer image in lightwave and import it into AE5/combustion, it cannot be used in the same way as a true RLA file for DOF (eg to prevent a blurred background spilling over foreground objects)

so... what is the problem with RLA on a mac?

PC newsgroups and PC users posting to mac newsgroups (eg dan ablan in comp.graphics.apps.lightwave) indicate that RLA exports depth buffers intact on PCs - but newtek people seem to attribute the problem to the applications importing the RLA files, or dismiss the z-buffer part of the RLA file as a 'wacky' addition to the 'core' RLA file ("hacked-on buffers")

z information is STANDARD in an RLA file - the 'wacky' buffer additions are contained in RPF files, which are discreet files with proprietary discreet buffer information embedded in them... if lightwave is supposed to be able to export z information, surely lightwave users can expect working RLA files?

if RLA export in an AE5/combustion readable format isn't possible, is there a way to embed a grayscale 8-bit z-buffer image into an RGB image in order to fool combustion into thinking the file is a legitimate RLA file plus depth buffer?

HELP!!!!

thanks - the SMFH foundation (the "save my hair" foundation)

By adam (24.76.122.7) on Sunday, June 03, 2001 - 04:27 pm:

thanks for keeping this issue alive...I've tried many times and don't seem to get any response from Newtek on this. Sure would love to export zdepth to ae5...sigh


Adam

ps...page still up at http://www.artifexstudios.com/zdepth

By Burner (216.37.4.71) on Wednesday, June 06, 2001 - 09:14 am:

Here are a few work arounds I've found:

You can get a regular Softimage or EI style depth map out of Lightwave. In the Scene>Image Process panel add a "buffer export" and choose "depth" as your output option.

This file won't work with AE's built in 3D channel tools because LW can't render out to the proper .eiz or .zpic format. You might be able to use a utility like file typer to change the creator type to .eiz and see if that works. (I haven't tried it.)

I generally use Puffins Compositte Wizard Super Rack Focus for DOF work, and a LW depth file will work great for that.

Note that depth files are non-anti-aliased. You'll have to render out at twice the size you want to use and scale down in your compositing program if you want clean edges. (You have to do this if you're using EI as well.)

For object tagging you can try rendering out a diffuse (not diffuse shading) pass.

Again just add a buffer export and choose "diffuse" as the option. Once you've done that you need to set discreet diffuse values for all the objects you want to tag. This probably means saving a separate version of the scene for that purpose.

So if you've got a cube, a sphere, and a cone you might set the diffuse values at 10%, 50% and 100%.

When you render the pass you'll get a cube thats nearly black, a sphere thats gray, and a cone tha's white. you can use difference matting to affect just the objects in those luminance ranges. It's a terrible hack, but it might help.

You could also do the same thing with LW's "special" buffers in the surface editor...but I'm not up on that yet.

A few other things to be aware of:

The file requestor doesn't allow you to choose a directory and type in a name. It only allows you to select a file and insert that as a path! Unfortunately the field doesn't track well with spaces or other mac like naming convtions. So unless you've got your mac set up to work like a pc (directory wise) type this info in yourself.

When I save a scene with buffer export plug ins in it and re-open it later I get a "Plug in image saver failed" when I try to render. To fix this I have to re-scan my plug-ins directory and/or nuke my Layout preferences.

I really hope Newtek is giving this area the attention it desrves. It's disappointing to see Newtek advertise the buzz word features and in reality have such poor support for the baseline features that a lot of users need to use every day.

As I become more familiar with LW I'm trying to move some of my paid projects from EI or Maya, but I can't do that when problems like this exist. They just cost me too much time.

By Burner (216.37.4.71) on Wednesday, June 06, 2001 - 01:47 pm:

Just a few additional notes:

It appears any value oriented buffers, like shading values, will be saved as a grayscale image, even if you pick a 32 bit format to save to.

Also I'm not sure if the "diffuse" or "diffuse shading" are working right or not. It appears there isn't a way to do a diffuse shadding pass without integrated shadows.

I can run an RGB pass to get my colors.

I can run a diffuse shading pass to get my tonal values BUT...

The diffuse shading pass integrates shadows into the pass. That makes the idea of having a shadow pass pretty useless.

There needs to be a way to pull a diffuse value pass without shadows, a color pass, and a shadow pass that can be integrated separately. So far I'm not finding this to be possible. (There is a geometry pass, but that doesn't seem to have the proper shading values when I compare it to a full up render.)

Is it possible in LW to globally tell the renderer to render without shadows? So far the only way I can find to do this is to turn off that value in each individual light.

It would also be nice if the shadow pass would export the full shadow buffer for an object rather than just the cast shadow.

When I'm comping shadows I sometimes need to choke or spread the shadow pass. When I've got a true shadow mask it's easy to do. With cast shadows you always have to deal with the problem of occlusion. When part of the casting object coves the shadow and you do any kind of size or focus manipulation on the shadow pass you have to deal with the uneven area created by the object occluding the shadaw. If you export the whole buffer you can deal with the overlap easily in the composite.

Take a look at how EI generates shadow masks. I don't know if something like this could happen in LW's special buffers or not, but it's an ideal way to get shadows for compositing.

By Nigel Hendrickson (24.168.21.68) on Thursday, June 07, 2001 - 08:04 am:

I'm also facing the task of doing several multipass renders out of Lightwave, which doesn't look setup to do this at all. Things that I took for granted in EI like flipping on/off various flags for diffuse, specular, reflections, shadows etc. at render time, appear to be a MAJOR pain in Lightwave. If these attributes can't be turned off/on globally for each rendering pass, must they be toggled for each texture and each light on each pass? And how does LW deal with an object passing behind and then in front of another object in the same shot? How does the shape of the foreground object get knocked out of the alpha channel of the background object?

I have lots of other questions, but this is just a start. I'm sure there are some LW veterans out there who have dealt with this before. Please tell me I'm missing something important. Useable RLA output would be a start, but I think it's important to at least have the more traditional techniques also readily available.

- Nigel

By Burner (216.37.4.71) on Friday, June 08, 2001 - 10:38 am:

Well here's what I've been able to divine from what LW render buffer export offers:

http://www.bennettinnovations.com/users/cweyers/r_pass/

I think the goal of the render buffer export is a good one. Theoretically you would be able to save images for all of your passes without having to create new scenes tailored to getting that specific pass.

However the implementation is off a bit IMO. You need the ability to render with and without shadows WITHOUT having to switch shadows off for all of your lights.

You need to be able to get a shading pass that doesn't have integrated shadows.

You need to be able to get a true shadow mask.

If those things could be changed it would be wonderful.

It would also be nice if there were a better interface for the plug. Adding the plug over and over again is a pain, and your directory path get's cut off by the small window size.

There's a plug for the PC that straightens this out, but there isn't a Mac version

By Stephen Enggass (206.26.225.33) on Thursday, June 14, 2001 - 08:36 am:

When using the 'buffer export' process, where do you find these files after rendering? I tried it last night for Depth but couldn't find the output Depth File? Where do you specify the output path?
Could someone briefly outline the process?
Thanks
Steve E

By Burner (65.7.229.79) on Thursday, June 14, 2001 - 05:09 pm:

When you add the plug-in there's a feild at the bottom of the screen to type in a path. Just type the path in, with colons in between each directory level.

There's a button there to let you choose a path, but it only let's you select a file and it will insert that directory path. You can use this to at least find out how the syntax works.

Also make sure you choose the right image type from the pop up.