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View Full Version : Hard to describe - Shade light bars on elevator shafts



IgnusFast
04-05-2011, 01:10 PM
I have a circular central shaft, say 400 ft tall, and about 60 ft wide.
Through that shaft pass 6 equidistant elevator cylinders, each about 10 ft wide (well, and a bunch of unrelated pipes and cables).

Each elevator shaft has a horizontal slot stenciled into it, which wraps approximately 1/3 of the way around it (the blue glows).

I'm trying to add a node setup that will shade these bars, but I can't seem to get it right. And I realize a picture of the nodes I've attempted would help - I'll post one once I get home.

The first node I tried starts the same as the second. Oh, and "Item" in this case is the hub object.

I take the vector from the Item Pivot node, and feed that into the X and Z coordinates of a Make Vector along with the Y coordinate from the Spot item. This should give me the X and Z from the center of the hub, but the Y from the impact point on my surface, if I understand even this much properly.

In the first method, I fed that resultant vector into an Incidence Angle, then feed that into the Luminosity Channel of the actual surface.

In the second, I fed that vector into a Distance node, and compare it to the Spot position. That in turn feeds a Gradient, which does distance-based shading.

The only problem is that this doesn't seem to work. For some reason, every even shaft is shaded properly, the odd ones aren't.

So I tried using a separate surface for each elevator, and it STILL doesn't work.

I'm not sure if I'm doing something wrong (likely), or if Lightwave is doing something strange (less likely)?

I'll post a simplified object when I get home.

Thanks to anyone with advice!

EDIT: It might have helped if I'd posted the effect I was going for in the first place. *Facepalm* I want the center of the bar to be really bright, which fades to almost black near the side edges.

IgnusFast
04-05-2011, 10:29 PM
Now I'm wondering if it's possible that either the Info node or Spot node don't respect the orientation of the parent object? I think some of them are off because the object is rotated in world space.

Still trying to nail it down, though...

IgnusFast
04-05-2011, 10:36 PM
Crap, never mind. Didn't pan out. Got rid of all the rotation and the damned thing is STILL canted. Not getting it. :(

jameswillmott
04-05-2011, 10:36 PM
Now I'm wondering if it's possible that either the Info node or Spot node don't respect the orientation of the parent object? I think some of them are off because the object is rotated in world space.

Still trying to nail it down, though...

The Transform node converts from object to world space and back, maybe that will help?

IgnusFast
04-06-2011, 05:02 PM
Sigh. I got it to where I want it to start... Attached is the packaged scene and stuff.

So I loaded the *full* scene with all the other objects. So between that and some rotation, there's no difference between the scenes. And guess what? It doesn't work.

I left a bunch of junk in the nodes from things I'd tried, but basically it's just the Spot node feeding an Incidence Angle node. And I really thought I had it this time.

I hate to just do it with a stinking image, but I think I'm about down to that.

Next post will be the images in the full scene. These are the images as I want them to look in the cut down scene, and the scene itself.

IgnusFast
04-06-2011, 05:03 PM
And here are the pics of the same object, and same basic scene. Just more objects outside the station.

jameswillmott
04-06-2011, 05:20 PM
I want the center of the bar to be really bright, which fades to almost black near the side edges.

Can you apply a weight map, or even a UV map, to the bars, so you can drive a gradient off the weight/UV value perhaps?

IgnusFast
04-06-2011, 05:46 PM
I probably can do something texture or map based; I'm just disappointed that I have to. I wanted to do it via nodes, using some of the math functions. And I just can't get it to work!! Frustrating.

IgnusFast
04-06-2011, 07:29 PM
Sigh. Went with UVs and a gradient image. At least it looks like I'd hoped.

I'll probably still play with it, but I'm still mystified as to why the mathematical approach doesn't work.

Tobian
04-06-2011, 11:02 PM
A weight map would probably work faster, and you can fine-tune it using a gradient too.

Intriguing scene, what's it for, I love the retro look and the bold colours of it!

IgnusFast
04-06-2011, 11:05 PM
I'm not even going to PRETEND it's as cool as Pluto Station; I just like making space ships. :)

This is actually a much older space station than the one I'd been spending the most time on. I just figured I should go back and give it some love.

I like the "World Of The Future" look, with lots of curves and glowy bits.

As far as weight maps... Since I've never used one, I'll have to do some research on that. Unless you know of a good tutorial.

IgnusFast
04-06-2011, 11:06 PM
BTW, my gallery is not that refined - it's just a collection of most of the crap I've done. But it resides, such as it is, here:

http://gallery.me.com/ignusfast#gallery

Tobian
04-07-2011, 12:31 PM
Here's a quick and dirty weight map tutorial. The 'weight blur' tool is really handy here, because it will let you easily blend weight maps so they are soft in gradient.

there's a bit inside my station which looks a little like that, just without the bold red/pink colour, and yes I do like the supercool 'world of tomorrow' look, and some f that will be making it's way into my interiors too, especially the rec-deck! :)

IgnusFast
04-07-2011, 08:38 PM
Possibly even more garish - playing around now. :)