I have a puzzling question for all the Material Room gurus like BagginsBill and others.

I had read last week on one of the CG forums on the web about something called (I think)  Incidental Invisibilty.  That may not be the actual term, but it was 100F+ in the room when I was reading, so my memory fails from hardware melting. :laugh:

What I mean is this: As the edge of area (like the cylinder of a light-sabre)  approaches the center, the texture of the ambient mateial becomes more visible.  The article went on to talk how it only works on cylinders and such, but NOT flat swords because of something dealing with 'Angle of incidence" due to the curvature of the mesh.

I would guess that mean as the Viewer (Eye or camera) is at a 90 degree angle to the mesh with this shader node on it, it appears completely solid, but the more it curves away from you, the more transparent it becomes until at the "edge on" of the mesh, it's invisible.

My question is this: Is this possible in the poser material room?

I have no immediate use for this, but the thought of blaster bolts and light-sabres with more "Realistic" (oh do shut up! :laugh: ) appearance would be a real boon to start with. If something exists, someone will use it!

Yes. The Edge_Blend node does this. You can use it to control any effect, not just transparency.

Sounds like an application of the Fresnel effect (I would give you the link to the RDNA thread on same but that's history now).  I have a render going just now or else I'd dig up a material that has this implemented and give you a screenshot, as Isaoshi says I believe it features Edge_blend node to control reflectivity based in the angle of the surface in relation to the camera (swiped from Bagginsbill's example).

Really?  Wow, that is SO cool!  I'll have to play around in the material room some more tonight!  So many hours in it, LOLOLOLOL:laugh:

(edit) oops, the Edge_Blend node was also controlling diffuse colour in this image, not just transparency.

If you were trying to fake something like a lightsaber you might try the same thing but with the Ambient_Color and value channels.

Of course there is Transparency_Edge and Transparency_Falloff - hehehe.

Are we talking about a glowing cylinder? The idea being that when you look "through" the middle of it, the glowing bits are more dense, whereas when you look near the edge, you're looking through less glowing bits? 

If that's the case, Edge_Blend'ing doesn't work so great - point the cylinder/sword at your camera - it's all edge then  At such an angle, you'd be looking through 10 times as much glowing stuff so it should be MORE dense, not less.

What you really need for this is a volumetric shader, like my new cloud-puff shader.

The interior is great, but how about the ends?  Does backfacing geometry or the end caps of the cylinder work against you here?  If so it wouldn't take me 5 seconds to give you a cap-less cylinder OBJ.

I wasn't worried about the caps because of course you can make it capless, or tapered, or whatever.

The real issue is as the sword points towards the camera, it disappears. That's not how it should work. it should do the opposite - becoming more opaque because at that angle you're looking through more of it.

Look here:

http://www.renderosity.com/mod/forumpro/showthread.php?message_id=3072203&ebot_calc_page#message_3072203

Back in 2007 I helped Molina00 design a light saber. The trick is to use a series of concentric cylinders, each with a different transparency. This is, in effect, simulating a volumetric shader, because we're sampling the volume at many points in the interior. It works great.

That's pretty smart, looks great also.

Here's the link to it if you wanna see how it works.

http://www.sharecg.com/v/14198/poser/Energy-Sword-v.1

That's pretty clever.  That's sort of like faking a cane of light with multiple cone props, like I saw a few years ago.  I've d/led it and will take a look at it.

I'm interested in the effect in IsaoShi's first image. I would like to be able to simulate the glow around a candle flame or street lamp. I don't want to have to use a multi-layer prop as in bagginsbill's suggestion for a light sabre, and as I only want to use this on a sphere, I don't think the same problems of camera angle apply. The only problems in IsaoShi's image are the grey appearance around the edge of the sphere, I would need it much lighter, I would also need the edge to fade to 100% transparent.

I'm a total dunce in the material room. Could someone post a screen shot of the set up, or instructions of how to do this?

Street lamp, candle flame and such was what I was thinking might have uses for this effect. I haven't had a chance to play in Poser since posting.  I'm in the middle of moving today.

lesbentley: I'm at work now, so I can't post any setup shot, but I'm sure others will point you in one or other suitable direction. 

As bb said, if you only want to adjust transparency you could use the Transparency_Edge and Transparency_Falloff channels on the PoserSurface. Increase the Transparency_Edge value to soften the edge, and play with the fall-off value to get the transition you want between zero and full transparency.

My test sphere was only grey around the edges because I inadvertently used the Edge_Blend node to reduce the diffuse colour, as well as to increase the transparency. My shader was already set up like this, and I forgot to unplug it before rendering, and I was too tired to do it again.

That looks really great, Raven. Elegant in its simplicity, too.

Is this one of the times it is ok to use Reflection_Lite_Mult?

Here's the same scene with it unticked. I can't see a difference, but I believe that setting is to do more with reflections rather than anything else. I could be wrong though! :)

That setting only affects what is plugged into ReflectIon_Color. In this case it doesn't do anything bad or good.

Quote - lesbentley, is this the sort of thing you were after?

Yes, that's exactly the sort of thing I was looking for. Thanks raven.

Damn, Rave, that kicks ass!  W00t for you!

If Bagginsbill likes it, that IS high praise indeed!  He never likes anything!  <<  >>

:laugh: LOLOLOLOLOLOLOL

Be careful, he will charge you premium rates for his next freebies.