View Full Version : :rips hair out: Why does LW suck with glass?!

August 2nd, 2002, 04:00 PM
OKay, I took the half of an outline of a bottle from Illustrator and brought it into LW where I lathed it in to the full object. Fine and dandy, cleaned up the points and whatnot... I lathed another outline to make the inside of the bottle and then added it to the outside of the bottle (I tried subtracting it but it wouldn't work). Well, now it looks like, even though it's not set as being double sided, all the polys are doublesided. When I copy the whole thing to make an "air layer" (which is the most ridiculous thing, stupid Newtek), and flip the polys, and render it, it has the most horrendous errors on it. When I don't flip them it still has errors.

It's driving me nuts. Help would be appreciated.

August 3rd, 2002, 09:43 AM
I think before bashing NewTek and their product, LightWave, you should realize that the reason why your glass sucks is because you're doing something wrong. It is my understanding that glass is created with only two surfaces. The first being the glass surface, and the second being the air surface. When you "added" another lathed section to the already present glass surface, you created an inward and outward pointing glass surface. This is wrong! You only need the outward facing glass surface and the inward facing air surface. Also, instead of adding the surface through a boolean operation, maybe you should try cutting the object and pasting it in the same layer. When you render, if you notice some errors, take it back into modeler and merge points.

August 3rd, 2002, 10:29 AM
The boolean is probably an extra step you don't need.

You should be able to lathe the interior and exterior of the bottle at the same time.

Darrell Lawrence
August 3rd, 2002, 05:17 PM
Not to mention, after lathing, you need to merge points (just in case) and definatly unify the polygons.

August 3rd, 2002, 05:57 PM
...sooo... Lightwave is utter crap at glass is it?


still think so?

tools or the workman - you decide...

August 3rd, 2002, 09:50 PM
Okay, I know quite well, Fabio, that when working properly that glass can look very nice in lightwave. Glass, however, is not something that I do often, hell, modeling is not something that I do often, so it's quite hard for me to troubleshoot things. Plus, the requirement of air polygons seems quite redundant and since everything has to be just right for them to work, it becomes a pain in the ass.

That said, logicially, it seems to me, that to make a bottle hollow, the shape used for the outside must be hollowed out, which is what I tried to do with the second shape. I'm thinking that maybe I should draw the outline of a hollow bottle instead of booleaning the bottle hollow.

Regardless, unless I'm reading the display wrong, after I lathe my initial outline, it looks like it's registering the polygons as double sided (I'm assuming that because the, I don't know the technical term, line that goes through the middle of the polygon when selected is showing up on both the inside of the poly and the outside.) This, I understand is a no no for glass, correct? YOu want glass facing out and air facing in and double sided makes it wrong.

I'll keep working on it.

August 3rd, 2002, 10:42 PM
Try these tutorials:

lathing a wine glass (http://lightwave.ancientfuture.net/html/tutorial01.htm)
Shiny refractive glass (http://www.geocities.com/CollegePark/9315/lw/tip4.htm)
What is the index of refraction (http://www.3dluvr.com/content/artz/refrac.php)
enahncing transparent stuff with gthick2 (http://www.happy-digital.com/freebies/tip_gthick.htm)

unfortunaterly most of the other glass tutorials are down at the moment but those should help you out

no double sided polygons not in the surface editor and especially not using the make double sided function in modeller

August 3rd, 2002, 11:37 PM
Beautiful examples, Fabio. Obviously, it's the workman. That's not to say that you're a bad artist, Kakaze, simply that you should not jump to conclusions so quickly. Anyway, I'm sure those tutorials will help you out. If not, you may try looking for one of the Inside LightWave books at your library. I'm sure there is a glass tutorial in the 5.6 version, but I am not sure about 6 and up. Let us know how your results come out.

August 4th, 2002, 02:14 AM
I figured it out without the tutorials.

Apparently, there were a bunch of extra polygons on it, directly on of the ones I wanted and facing the other way...at least, that's what it looked like. Anywho, the Unify Polygons tool did the job and the glass is working fine now.

If those tutorials have good info on surfacing, however, I could use them. One of them looks familiar though just from the title, so I'm wondering if they aren't ones I've seen already. I'll find out. Any that teach you how to put liquid inside? Thank you, btw, Fabio.

When I get frustrated I yell and scream and jumparound...don't mind me. I usually work things out eventually. Don't take much mind of me.

Darrell Lawrence
August 6th, 2002, 01:27 PM
...and I'm gonna guess you needed to UNIFY those extra polygons? :)

August 6th, 2002, 06:04 PM
Yes. As I said, the Unify polygons option did the job.

Something I don't remember having to use before :furrows brow:

I don't know why I even try modeling things...and this wasn't even anything complicated.

Darrell Lawrence
June 5th, 2008, 09:39 PM
*bump for the tips and moving to the Help Zone*

June 6th, 2008, 12:22 PM
Criminy...this is old.

I haven't even touched Lightwave since around the time I had finished this project :\

Darrell Lawrence
June 6th, 2008, 01:22 PM
So you did finish it? Where's the pics?

June 6th, 2008, 07:39 PM
Yeah, I did finish it. I found an awesome glass surfacing tutorial and I used that to surface the bottle I made and it had information on how to create a really nice background in it that I used too.

It's been so long since I looked at it...I didn't realise how dark it came out. I should've added a light in the in front of the bottle too.

Darrell Lawrence
June 6th, 2008, 07:50 PM
That's pretty good :)

Let's see ya model more :D

June 6th, 2008, 09:24 PM
I'm lucky I was able to do that. Thank gods for the lathe tool. I've never been able to wrap my head around proper modelling.

Darrell Lawrence
June 6th, 2008, 09:31 PM

June 7th, 2008, 04:15 AM
I practice every day .. :)

Darrell Lawrence
June 7th, 2008, 04:16 AM
...and you're getting damn good :)

June 7th, 2008, 04:22 AM
High praise warrior thanks ..

June 7th, 2008, 11:58 AM
I would love to but there is absolutely zero motivation, sad to say. I used to love doing art but now I just can't get myself to even care. :(

Darrell Lawrence
June 7th, 2008, 04:07 PM
...but... we need some bottles with liquids and glasses to drink from for the Gladiators around here :D

June 7th, 2008, 09:07 PM
Well, I'm sure there's a Wal-Mart somewhere around you can get them from :p