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Serling
10-06-2012, 08:19 PM
I'm currently modeling a Jack-O-Lantern for a project but am running into trouble: every time I try to "carve" (Boolean) holes into the subpatched mesh, things get real ugly (N-gon issues arise).

Even when I freeze the mesh before a Boolean, I still get odd missing and overhanging polys where certain edges are created. It's driving me crazy.

Does anyone know of a good tutorial for cutting complex shapes into Sub-patched meshes?

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nickdigital
10-06-2012, 08:32 PM
How dense is your frozen mesh? Also try tripling it before doing a boolean.

Serling
10-06-2012, 08:41 PM
How dense is your frozen mesh? Also try tripling it before doing a boolean.

Not to dense (level 2 Sub-D). I was trying to keep the poly count low. Will try the triple trick. That sounds promising.

Serling
10-06-2012, 08:52 PM
Sub-patched and frozen at level 4 then tripled. This is the result I keep getting. Is there any program out there that does booleans well?

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Kryslin
10-06-2012, 08:58 PM
Hmm, I would use solid drill to stencil the design into the unsubd'd cage, inset it slightly, and bridge it, then subD it.

If you have LWCAD, you could slice the design into the cage using the Line and Curve Booleans...

I just went through something similar, trying to cut cockpit glass into a subD aircraft hull.

Sensei
10-06-2012, 08:59 PM
Is there any program out there that does booleans well?

No... ;)

Nobody uses boolean while organic modeling..

nickdigital
10-06-2012, 10:23 PM
Yeah I normally do what kryslin does if a normal boolean doesn't work.

bobakabob
10-07-2012, 01:56 AM
This Trueart plugin looks like it would help http://www.trueart.eu/?URIType=Directory&URI=Products/Plug-Ins/EasySplit
Otherwise subdivide the object with Metaform to give yourself more polys to play with, delete polys for eyes and mouth, pull vertices into place and use Thickener. Booleans tend to be too unpredictable.

Serling
10-07-2012, 02:00 AM
I gave up on trying to cut any holes into the mesh and, instead, stenciled (drilled) some background polys onto the mesh, selected all the polys inside the stencils, then used the extender + scale + move tools to create this result.

I still have to do some surfacing, but this will work given the amount of time it will be on the screen (about 1 second.)

Update with some surfacing and lighting...

Lewis
10-07-2012, 02:11 AM
Yeah Booleans are filthiest operations with Polygonal modeling. Go to NURBS package, drill it, add fillet on edges and bring back polys for rendering :).

Or spend half day doing fixes for Subds mesh after boolen :D..

Serling
10-07-2012, 02:40 AM
And here is the last bit of surfacing and lighting on it.

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Lewis
10-07-2012, 02:59 AM
Hmm, to much light/glow inside for my taste. It should have candle light inside so this is way too bright. But texture on pumpkin is quite good :).

Serling
10-07-2012, 03:03 AM
Hmm, to much light/glow inside for my taste. It should have candle light inside so this is way too bright. But texture on pumpkin is quite good :).

That's why I was trying to cut the polys out instead of just extruding them inward: I wanted the kind of lighting falloff you'd get with a candle (light source inside it). But I couldn't cut out the polys on a subd surface and get it to look like this, so I took this instead.

If the boss approves it, it will be on screen no more than one second anyway (to be used as a keyable transition over video.)

And thank you for the good word on the surfacing. :)

ShadowMystic
10-07-2012, 03:56 AM
That's why I was trying to cut the polys out instead of just extruding them inward: I wanted the kind of lighting falloff you'd get with a candle (light source inside it). But I couldn't cut out the polys on a subd surface and get it to look like this, so I took this instead.

If the boss approves it, it will be on screen no more than one second anyway (to be used as a keyable transition over video.)

And thank you for the good word on the surfacing. :)

I disagree on the surfacing comment... The bump is far is too pronounced, and the internals of a pumpkin are a translucent, fibrous, tissue that give a jack-o-lantern their signature eerie glow. Also I'd cool the light into a bluish 'moonlight' hue for contrast.

XswampyX
10-07-2012, 05:01 AM
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I have to agree. :i_agree: Try the sigma2 node for a start. Here's a quick test. Notice how the stalk looks a different colour, even though it has the same surface. That's down to lighting.

probiner
10-07-2012, 06:29 AM
+1 for Nurbs if you want to use the boolean mindset and the mesh won't be deformed.

You can model that with subds for sure, you just have to do the final volume and not separate volumes and then try to join them. But in order to hold the correct roundness of the shape and abrupt clean cuts/insertions, you will notice the mesh density rise as the model complexity rises too and will mess with the interpolation on the border vertices.

If LW had a retopo utility you could slap new polygons on the shape and work around those holes. As for now such task is not fun at all and the tweaks are time consuming.

Anyway, a quick example of what you could do. Notice each sharp corner needs 3 edges and there's an attempt to line up things with the existing topology.
http://i153.photobucket.com/albums/s202/animatics/Lightwave/pumpkin.png

red: Border vertices will require some tweak, since the new mesh will put them out of shape through SubD interpolation.
orange: Inset of the hole, required to minimize any artifact in the edge zone.
green: The hole's edge.

The opening will be the negative shape of this (Edge Loop and Cross Hatch almost in the bootom of the page): http://lightwiki.net/wiki/Fundamentals_of_Subpatch_Modeling_Part_Two
A practical example of this mindset by JeffrySG: http://www.pixelandpoly.com/video012.html (oops, seems like Jeffry took it offline).


Cheers

Serling
10-07-2012, 06:31 AM
OK, I cut the bump in half (from -50 to -25%), added a blue fill light to simulate moonlight and changed the color on my key light (right) to orange, to simulate the look of a porch light. Here is that render...

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I still like the more pronounced bump of the last render, but the blue fill does certainly add some drama to the shot. :)

BeeVee
10-08-2012, 04:07 AM
Have a look at Richard Culver's excellent series of guides to subpatch modeling on LightWiki (http://lightwiki.net/wiki/All_about_Subpatch_Modeling) too.

B

Serling
10-09-2012, 02:02 AM
Remodeled "Jack" for the practice, this time setting Sub-D level to 2 (keeping the poly count manageable) then tripling the mesh before drilling into it. This is looking more like what I saw when I envisioned this. :)

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Not done with the surfacing, but the lighting is more the way I wanted it.

BeeVee
10-09-2012, 03:19 AM
Is Jack going to deform? If not, then there is no need to keep him in subpatches. You can freeze.

B

Serling
10-09-2012, 03:43 AM
Is Jack going to deform? If not, then there is no need to keep him in subpatches. You can freeze.

B

Yeah, sorry...forget to add that I froze him before tripling. Froze at level 2 Sub-D.

jwiede
10-09-2012, 04:58 AM
Remodeled "Jack" for the practice, this time setting Sub-D level to 2 (keeping the poly count manageable) then tripling the mesh before drilling into it. This is looking more like what I saw when I envisioned this. :)

108436

Not done with the surfacing, but the lighting is more the way I wanted it.
Bump still seems a bit too pronounced, and the bump texture seems a bit "off" for that of a pumpkin which is bugging me a bit (doesn't look like that of long-strand fibrous material inside with very thin "skin" over, nor for the cuts into the stringy, fibrous "meat"), but shaping up quite nicely in any case.

Serling
10-09-2012, 11:39 AM
Bump still seems a bit too pronounced, and the bump texture seems a bit "off" for that of a pumpkin which is bugging me a bit (doesn't look like that of long-strand fibrous material inside with very thin "skin" over, nor for the cuts into the stringy, fibrous "meat"), but shaping up quite nicely in any case.

I'm using the procedural texture "crumple" for the bump in the node editor. I tried a number of combinations trying to produce a "stranded" effect - orienting the texture along an axis - (especially in the stem), and nothing seemed to be working. I even tried the Simple Skin node and gave up on that after an hour.

Here is the latest with some tweaks to the lighting and texturing on the stem. Thanks for the feedback, guys.

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ShadowMystic
10-09-2012, 11:06 PM
I am about to go William Vaughn on your butt. "References, references, references!"

You're missing your texture mark because you aren't looking at real life. A pumpkin's skin is relatively smooth with a slight bumpiness. Increase the scale of your texture while slightly lowering the texture value, layer value, and bump percentage. i usually play with all three of these to get a bump that's believable. Also, consider adding a weak turbulence layer for roughness.

post the file if you'd like. I could tinker with it.

Serling
10-09-2012, 11:21 PM
You're missing your texture mark because you aren't looking at real life.

"Ceci n'est pas une pipe." :D

Serling
10-10-2012, 09:07 PM
Here's the latest mesh if anyone want to take a shot at texturing it.

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Version 4 has the Sub-D mesh, version 5 is the frozen and tripled version.

hrgiger
10-11-2012, 08:05 AM
As far as using booleans go, I would have avoided the whole mess and modeled the openings from the start instead of trying to add them later.

UnCommonGrafx
10-11-2012, 08:22 AM
As far as using booleans go, I would have avoided the whole mess and modeled the openings from the start instead of trying to add them later.

And then used thickener.

probiner
10-11-2012, 08:39 AM
Multishift! :p
But yeah, that's a better approach.