Topic awaiting preservation: Multi-Pass #6: Stupid Vase

Time to test a few things.
I know should be working on that other thing, but I was struck by an idea recently.
So, here we go.

Nothing fancy. Just a vase with no real environment except for one shadow pass to suggest a surface. (I know you folks can add a surface for the vase to sit on with no problem, so there you go.)

Ah, but there is a trick in these passes: seperate flipped normal renders.
I was watching Making of Shrek 2 and they showed a quick little demo of what they called a translucency shader. The cool thing about their shader is that it's grey scale across a wide spectrum across more of the mesh than necessary thus making it extremely tweakable.
The question: how to hobble together my own translucency shader with the same tweakness but only with the tools that I have with out getting too fancy?
Answer: one pass of z-depth, flip the normals and another z-depth.
Take them both into PS and line them up.
Set top one to Difference.
Ad-Layer > Levels > Auto Levels
Tada.
One tweakable translucency pass based on mesh thickness.
After that, it's just a matter of using it with the other light-based renders and things.
You know, ChOps and blending modes and junk.

Of course, not with out problems. What simple tool hack doesn't have problems?
For one, it's not that good for "overlapping" mesh parts.
There are a few other minor things, but nothing you folks can't figure out and hack around.

Wait...
One of the other problems is that more than one pass for the other things has to be made if you are doing something extremely transparent.
So you can do back-face specular and back-face this-n-that.

Doh! Overlapping mesh parts!
Um... this is a problem considering the vase.
I'll have to figure something out and redo a buttload of renders.

:sigh:
If you want to get a headstart on messing around until I can fix the overlap problem, feel free.

Multi-Pass #6

Mostly PNG files. Between 120k-190k or so.
With transparency, so watch out for that.

edit:
Figured out the back-facing overlap problem. Ugly hack.
Not sure when I'll get some new renders up just yet.

(Edited by warjournal on 05-18-2004 02:28)

Constantly amazed Warj. I'd like to watch over your shoulder one day. =)

If I ever get around to running a Ventrilo server again, you might kinda get that chance. You might a glimpse into my methods and thinking beyond what I babble about in these parts.

Minor Update

My approach is good, but flawed because of the overlapping mesh parts. I knew overlapping was a problem, but I just didn't realize that I was perpetrating it. Technical thinking and wisdom don't always go hand-n-hand. I freely admit it. Heh.

I've got the various parts for the shader built.
1. A true object z-depth surface shader. Not based on true viewing angle as it is kind of baked in. That is, you can change viewing angle and the shader doesn't follow unless you tell it to. So, you can actually have object z-depth based on angles other than viewing. Pretty neat trick.
2. Opacity based on #1. Toss shader #1 into opacity, tweak, and you can "slice" the object.
3. Opacity based on camera/lighting combo rig. With this, you can render out the hidden parts of the mesh due to overlapping. If one part of a mesh is hidden behind another part of the mesh, this will render just the hidden parts.
4. Radial opacity kinda. Bah.

For the vase, I'm going to have to use all of that, plus a few more tricks, to do four very specific renders. Then it's off to PS to slap them together for a final translucency map. I would ilke to just do some sloppy renders and then kind of free-style it, but my technical side is over-riding my creative side. I'll be sure to include some quick, non-technical renders for you folks that prefer to free-style it.

Ugh!
I don't know how or why this happens to me. I'll take the simpliest of ideas and end up in the most bizarre places. I might have to start taking more complete notes so the world will know my true genius after I'm gone. Bwahahaha!
As Daffy Duck said, "It's mine! Mine! Mine! It's all mine!"