Mini Challenge - Champaigne/Wine Glass

[Azeiku]

Is there a time limit? Or does it end in a day or two? Are we going to run this like the renderosity mini-challenges?

-Azeiku

[Rani]

There is no time limit.
The idea is to learn diffrent techniques to do the same thing.
It's like the renderosity mini challenges.

[Lord Banshee]

I'll start it off

http://img9.imagevenue.com/loc208/th_7bd_glass_curves.jpg (http://img9.imagevenue.com/img.php?loc=loc208&image=7bd_glass_curves.jpg)

1) Draw curve of 1 section of the glass by using line, circle, fillet, trim, arc, InterpCrv, and many more ways

[/url]

[URL=http://img17.imagevenue.com/img.php?loc=loc285&image=425_glass_finsih.jpg]http://img17.imagevenue.com/loc285/th_425_glass_finsih.jpg (http://img9.imagevenue.com/img.php?loc=loc208&image=7bd_glass_curves.jpg)

2) Revolve command, Select Curves, Enter, Draw axis from center of cup to verically down, enter, "OK" on dialog, Select newly created surfaces, join
3) Right click Prespective title, Rendered Display

[andrewjohn81]

I'm all for the simple ones, but that one is just too easy. Since they actually lay that one out for you in the tutorials that are in the help file or manual I think something else would be in order.
Just my opinion though.

[Rani]

http://img12.echo.cx/img12/5886/17by.gif

The top part was made of a Parabola by focus (MarkFocus=No Half=yes), then I used offset curve on it to create the inner part and used blend curves on the two top edges of the two parabolas to connect them.

The bottom part was made with two polylines and a curve, then I filleted them in order to have smooth edges.

I connected the top and the bottom parts by creating a circle and using it to cut the outer parabola and the polyline, then I blended them together.

I joined all the curves, revolved and voila!


http://img12.echo.cx/img12/1693/20kj.gif

Red - Polylines.
Blue - Fillets/Blends.
Green - Parabolas/Curves.


Thanks to ImageShack for Free Image Hosting (http://www.imageshack.us/)


EDIT: I agree with andrewjohn, this specific mini challenge is too easy IMHO, It's all about curve and revolve (though there are other ways...), there is realy nothing more into it, unlike the beaker mini challenge I linked from renderosity which has a 'trick' part, which is also the cause for the diffrent approaches.

[EighthDecay]

I don't have allot of time to play, but how about I suggest something for someone to try.

do 2 cross sections that are the same curve but one is modified a little, then array these like 4 each, so that you get a flower like shape from the top view.

do a closed loft.

[DarkSaturn]

http://www.darksaturn.com/other/rdh_wine.jpg

Top and bottom are rail revolves. Middle section was defined from two edge curves, then using those edge curves as the rail for a one rail sweep with a semi-circle (forming two halves, which could then be joined). As the fillet command can be slow and error prone, I find it easier to use the curve blend tool to create smooth edges on the initial curve. For the stem edge curves I used circles and the Line: Tangent to Two Curves tool to get a nice flowing shape that maintained a constant gap between the two sides.

[andrewjohn81]

I've got one.

See if someone can successfully get the rail revolve to work. Create an oblong lip to the glass, but keep the base round.

the rail revolve always messes up horribly when I use it. I always have to find another way to do what I want.

[tilite]

ok so here is the rail revolve... kinda just wanted to do it so didnt follow any guidlines... no issues wiht it... its actually an extreemly handy tool. i like it alot.

so yeh no issues worked first time

sry about the slack imagery there just desktop shots and at this hour i couldnt even be bothered taking them into photoshop and cropping... my bad apologise.

so in the red corner we have the profile crv... made of 1 single crv... told ya couldnt be arsed :shrug: ... in the green corner is the rail crv and the blue crv is the axis.

http://img5.imagevenue.com/loc198/th_2aa_ra01.JPG (http://img5.imagevenue.com/img.php?loc=loc198&image=2aa_ra01.JPG) http://img10.imagevenue.com/loc67/th_2a1_ra02.JPG (http://img10.imagevenue.com/img.php?loc=loc67&image=2a1_ra02.JPG)

funny thing is i could be arsed pulling some cntrl points in to make a straighter shaft. but couldnt be arsed editing simple materials..

http://img25.imagevenue.com/loc20/th_f5a_ra03.jpg (http://img25.imagevenue.com/img.php?loc=loc20&image=f5a_ra03.jpg)

hope that helps

edt: sry i forgot ur work doesnt like my host site. so here are the attchments
edt... edt: for some reason they are only partially uploading????

[erlik]

This one was created without a single revolution.

Upper part was a paraboloid, offset for the inner surface. The base is a truncated cone. Upper surface of the cone was extracted. The edge of the hole duplicated, reduced in size, moved up a bit and then extruded until it was a bit under the outer paraboloid. then the duplicated edge was projected onto the outer paraboloid, which was then split by the curve. And then I simply blended the extruded-curve-surface with the base and the outer paraboloiod, as well as the outer and the inner paraboloids. Voila. :D

Oh, yes, I filleted the edge of the base.

Eighthdecay, if you mean what I mean, you can also get that by sweeping curves and then blending/matching/merging the resulting surfaces. I'll try.

[Lord Banshee]

DarkSaturn,
what renderer did you use, thanks?

[DarkSaturn]

DarkSaturn,
what renderer did you use, thanks?

Rendered with Flamingo, it has its limitations but does a pretty good job of glass.

[andrewjohn81]

that's not quite what the rail revolve is for, but I tried it and now I seem to be eating my words.
I am all of the sudden having no problems with it.
I often have to rebuild indented buttons from ProE. The problem is they usually end up being not quite round, so I can't just revolve a profile from it or anything like that. When I try rail revolve on those I usually end up getting a horrible mess around the origin point of the profile curve. That shouldn't happen, and I don't know why it was happening, but I can't seem to duplicate the problem now so I guess it's ok.

[elagman]

Dark Saturn how did you get the top and bottom shapes with a rail revolve. Does the curvy side profile of your glass revolve around your top lip circular curve? I thought you have to have a straight axis to revolve around. Im confused :sad: The only thing I rember the rail revolve being used for is like a star shape that has a circluar arc revolving around it like in the manual. I have never used it for things like this. I feel amazingly stupid right now. Maybe its the beer im drinking. Don't drink and model lol!

[DarkSaturn]

Dark Saturn how did you get the top and bottom shapes with a rail revolve. Does the curvy side profile of your glass revolve around your top lip circular curve? I thought you have to have a straight axis to revolve around. Im confused :sad: The only thing I rember the rail revolve being used for is like a star shape that has a circluar arc revolving around it like in the manual. I have never used it for things like this. I feel amazingly stupid right now. Maybe its the beer im drinking. Don't drink and model lol!

Sorry, mis-typed there, just a regular revolve around a vertical axis.

[elagman]

Sorry, mis-typed there, just a regular revolve around a vertical axis.

Still confused. If you revolved around a vertical axis how did you get the bends in the neck?

[DarkSaturn]

Still confused. If you revolved around a vertical axis how did you get the bends in the neck?

Ah, only the very top (wine cavity?), and the base are revolved around an axis. The middle tubes are built by sweeping along a curve, you can see my base curves on the very left hand version of the glass. Basically I created two sets of curves, and the swept a semi-circle along each of them to make up the two sides of the stem pieces.

http://www.darksaturn.com/other/015.jpg Here are all the pieces seperated.

[elagman]

Ok got it now. This is how I would have done it also. For a minute there I thought I was crazy. Thanks for your patience.

[kiwi8]

I dont drink wine but I do shots!
made in same way as others using revolve
rendered in c4d

[erlik]

EighthDecay, is this what you meant by "flower shape"?

http://www.niribanimeso.org/gallery/glass.jpg

[EighthDecay]

yep that is more interesting to look at, how did you go about it?

thanks man. :D

[tilite]

i havnt really used rail revolve till i did for andrew earlier in this thread... but it looks to me like it was just 1 rail revolve and 2 blends??? am i close???

[erlik]

Nope. :D

Created the profile curve, mirrored it so I got, basically, a cross section of the whole glass. Then drew a circle with the diameter from the bottom end of one curve to the other.

Then drew a deformable circle with 16 points from one top end to the other. Turned the points on the deformable circle and selected every other point and scaled down in 2D.

Used the profile curves as rails and the circles as the starting and ending cross sections. Did a 2-rail sweep.

then offset one of the profile curves, cut it approximately where the bottom of the bowl should be. Mirrored it, did a tangency average match without joining, deleted the mirrored curve. Then did the position match (no averaging or joining) between the top of the inside curve and the outer profile curve. Did rail revolve of the inside curve on the top, deformable, circle.

Reversed the direction of the normals and joined with the outer surface. Capped the outer surface, extracted and the deleted the upper cap, and then filleted the base edge.

Writing this took almost as much time as the actual process.

In the meantime, I wasn't satisfied with the shape blending, so I took the bottom circle and copied it where I wanted the blend to start, a bit above the stem, scaled down in 2D untill it was about the same diameter as the distance between the profile curves, and then did the 2rail sweep.

Repeated the proces of offseting and cutting the curve for the inside surface together with the matching, duplicated the circle above the stem, moved up a bit, scaled it up in 2D untill it approximately matched the distance between the inside curves at that location. Added a point at the end of one inside curve.

Selected both inside curves as rails and did a 2rail sweep with the deformable circle, circle and point as cross-section curves. Now the blending between the round and "flower" shape is smoother.

Smooth mesh for export is about 8000 polygons. I'll post a pic as soon as I upload it. BTW, writing this part took more time than adjusting the shape blend in Rhino.

[erlik]

First, the shaded modelin Rhino. I hope you can see that the blend starts above the stem, and that there's no ribbing at the bottom of the bowl.

http://www.niribanimeso.org/gallery/glass_shade.jpg

And then the curves I used to create the glass, as well as a render in Bryce. I forgot that I filleted the bottoms of the curves because it's easier than filleting the edge of the base. Red are the outer curves and yellow the inside ones.

http://www.niribanimeso.org/gallery/glass_curves.jpg

[wild-brendan]

As silly as modeling a glass is, i'll do it anyway to support the Rhino forum.

Well, here it is: a rail revolve and a twist

http://img235.echo.cx/img235/4067/18km.jpg

Then it went in the oven (Flow along curve):

http://img235.echo.cx/img235/8159/28zw.jpg

My poor glass got over cooked :( Ahh well, neva said i was any good a glass blowing...
Make the next challenge a little more 'interesting'.

[Azeiku]

Last night I was playing with my eval version (I also don't have the internet at home) and was trying to place fluid in my glass. I had some strange double surface artifacts. I would post it here but I didn't grab any screens. I could reproduce in in a hurry I'm sure. This is what I did.

1. Use a polyline to draw the outline of a wine glass so I can revolve around the center axis.
2. Then draw a line from the center axis to the inside edge of the glass to look like a fluid (wine, water, whatever)
3. I copied in place the original curve from the actual glass. Split it and deleted the outer portion I didn't need.
4. Revolved the glass, changed the material to clear glass.
5. Revolved the fluid, changed the material to redish looking glass/fluid (didnt change the index of refraction IOR)
6. Rendered in flamingo.

When I was done rendering it gave me weird spots where the fluid met the glass. Looks like artifacts from two surfaces touching each other. Sometimes it was red sometimes it wasn't as red.

So my question is, is this normal and if so, what do most people use to make it look like there is actually fluid in the glass? Do you offset the fluid curve before revolving so the two solids overlap? Do you offset the fluid curve before revolving so the two solids have a small air gap between them?

What do YOU do?

Thanks,
Azeiku

[elagman]

So my question is, is this normal and if so, what do most people use to make it look like there is actually fluid in the glass? Do you offset the fluid curve before revolving so the two solids overlap? Do you offset the fluid curve before revolving so the two solids have a small air gap between them?

What do YOU do?

Thanks,
Azeiku

From my experience this is normal. Two clear surfaces that touch will mess up in most rendering apps. I usually offset a curve from my inner glass surface just a bit like .005" or something. Revolve and then cap that surface. Remember liquid usually has a slight radius where it meets the glass. Fill a glass and look closely at the top of the liquid where it meets with the glass, and you will see what I mean. Hope this helps.

[tilite]

i have a proposal for a new challenge... it doesnt have to be this particular concept but the creativity factor can be explored a whole lot more..

so i recently have grown an obsession with the sopranos... almost finnshed downloading the first series:thumbsup:

so possibly we could model something within that concept... i dont know... something very narrow minded like a gun or a cigar... poker table.. something organic like a chick (proper breast essential) on a strippers pole... somethign liek that. so you mix the creative juices and come up with a cool idea, model it, and as long as it is liked back to the sopranos... its all good:D

i dont know if everyone like the sopranos it one of those thing you love or hate.. so maybe a topic related to the mob!
we havent run this thread into the ground yet but people are extreemly capible
so thoughts... suggestions for a new challenge thread???

[erlik]

From my experience this is normal. Two clear surfaces that touch will mess up in most rendering apps. I usually offset a curve from my inner glass surface just a bit like .005" or something. Revolve and then cap that surface.

Not a bad suggestion at all, but I'd also recommend to look at the surface direction. the "liquid" has to have normals looking out, towards the glass. I've been doing that and I haven't noticed problems either in Bryce or in Cinema.

[Azeiku]

I dont' think I've ever watched the Sopranos so I don't know much about it. It's cool if people want to do that. I just might not participate in it. Which is find I have plenty of other things to do. ;-)

Azeiku

[andrewjohn81]

I also don't care for the sopranos idea.

Reguarding the double surface problem with the liquid:

The top of the liquid should be obvious. Someone already mentioned the meniscus (the little curve where the liquid touches the glass). Also take note that water would have a different one than alcohol.
Create that, whichever method you wish. Then split the glass object using the water's surface. Join the bottom half to the water surface, that is what you want to apply your liquid shader to. The rest will be the glass.

The reason you want to do it this way is due to how refraction works. This is in most raytrace programs. c4d uses Final Render, so I know that one should be correct, Mental Ray also works that way, but I know there are a couple where you actually need an offset to get it to work properly.
If you are casting photons through objects to get volume effects then you will have to have solid objects for that to work properly. So you would have to offset the glass a very small amount to get that to work.
If you are going to offset the glass, it is best to do it in polys. If you do it in nurbs then the polygons may not line up and intersect eachother because they may have different tessellation.

Hope that helps a bit.

[Azeiku]

Ah, so let me see if I understand this. So the actual surface of the glass where the water or wine would be touching the glass is removed and replaced with just the liquid surface. Thus eliminating the double surface and only having one surface there? Is that what you mean? Cool! It makes sense and I don't know why I didn't think about that. It's computers not reality. ;-) I'll try that when I get home tonight. Sounds like fun... and tricky! ;-)

Thanks!
Azeiku

[Rani]

Last night I was playing with my eval version (I also don't have the internet at home) and was trying to place fluid in my glass. I had some strange double surface artifacts. I would post it here but I didn't grab any screens. I could reproduce in in a hurry I'm sure. This is what I did.

1. Use a polyline to draw the outline of a wine glass so I can revolve around the center axis.
2. Then draw a line from the center axis to the inside edge of the glass to look like a fluid (wine, water, whatever)
3. I copied in place the original curve from the actual glass. Split it and deleted the outer portion I didn't need.
4. Revolved the glass, changed the material to clear glass.
5. Revolved the fluid, changed the material to redish looking glass/fluid (didnt change the index of refraction IOR)
6. Rendered in flamingo.

When I was done rendering it gave me weird spots where the fluid met the glass. Looks like artifacts from two surfaces touching each other. Sometimes it was red sometimes it wasn't as red.

So my question is, is this normal and if so, what do most people use to make it look like there is actually fluid in the glass? Do you offset the fluid curve before revolving so the two solids overlap? Do you offset the fluid curve before revolving so the two solids have a small air gap between them?

What do YOU do?

Thanks,
Azeiku

Can't help you much about rendering, but as far as modelling fluid in the glass I can advise you to use boolean diffrence and it will fit perfectly to the glass.

[elagman]

Here is my go. Simple revolves, and split surfaces for the frosted area along the neck. Wine is offset .005" Rendered in Rhino with Maxwell Alpha plugin.

[wild-brendan]

elagman: Model...meh...its ok. Render, now that is nice. What's Maxwell Alpha plugin and where can I get it?

[elagman]

elagman: Model...meh...its ok. Render, now that is nice. What's Maxwell Alpha plugin and where can I get it?

Yeah the model is totally lame. To tell you the truth I was testing maxwell more than coming up with a cool wine glass. :blush: Busted.....

You can go to www.maxwellrender.com (http://www.maxwellrender.com) to check it out.

They also have a good forum with a rhino group down at the bottom http://www.maxwellrender.com/forum/

[Azeiku]

Yeah the model is totally lame. To tell you the truth I was testing maxwell more than coming up with a cool wine glass. :blush: Busted.....

You can go to www.maxwellrender.com (http://www.maxwellrender.com) to check it out.

They also have a good forum with a rhino group down at the bottom http://www.maxwellrender.com/forum/

I agree! That render is sweet! That's almost VRay quality. ;-) heh

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