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etyrihje
06-07-2006, 03:51 PM
I have been using LW part time for three years, but I have mainly done buildings and architecture, using the basic shapes and my favorite tool the bolean tool...

I have barely scrathced the surface of subpatch modelling, I built a toon character, but subpatch modelling is so far from the other apporach, and keeps messing with my brain...

I want to build a large oil tanker (ship), and I can imagine how to get the main shape of the hull, but how do I make square holes in the hull, using bolean produces weird results...

What I am asking here I guess is to be pointed to a good crash-course in subpatch modeling... I have the "inside lightwave" books #7 & #8, any other sources that any of you would recommend?

Any hints and tips appreciated!

Thanks

Silkrooster
06-07-2006, 05:03 PM
I am no expert with sub patches but here is my theory, all subpatch models are created with 4 point polygons so, you should be able to use the knife tool and create 4 lines where 2 will intersect with the other 2 lines, then select the center poly on both sides and use the bridge tool, instant hole.
Silk

Penforhire
06-07-2006, 05:14 PM
"Inside LW 8" has enough info to get you rolling if you work through the tutorials (e.g. the cell phone exercise but imagine the buttons going down instead of up). I'm a FNG too at LW but I'd suggest deleting the polygons where you want holes and using Extender to make walls going inside the ship. Knife or Bandsaw can be used to sharpen up the edges near corners (adding narrow polygons very near the edge).

Another alternative would be to Smooth Shift a polygon(s) where you want a hole and move the new shifted polygon(s) down. Seems like the trick is getting the polygons in just the right places for your holes. Tools like bandsaw followed by band glue seem to do that trick (moving ploygon edges without distortion) well.

hrgiger
06-07-2006, 05:21 PM
Hi etyrihje. Is the hull rounded? Because if so, it may be near impossible to cut square holes due to the nature of subpatch. Well, it is possible, but it's not easy especially if you're not an experienced modeler who has a good understanding of the way that Lightwave sudivides the mesh. You can use booleans but it requires some clean up afterwards to make all polygons contain either three or four points. Anything else can't be subpatched.

Your best option might be to freeze the model and then use booleans. This will allow you to cut whatever shape you wish into the model.

In LW9, you will have the option of using Catmull Clark subdivsion which will not only allow more then three or four points per polygon, but it will also allow you to use edge sharpening which will give you more options in obtaining the shapes you're after.

Good luck. If you want more individual help, send me a private message with any questions you might have. I might be able to provide some help with your model file.

oDDity
06-07-2006, 05:33 PM
THe basic principal to know is that a square polys will become a circle in subpatch mode, so what you need to do is add some cuts very close to the hole. The closer the cuts, the more square the shape will remain when you subpatch it. For this you'd need two cuts around every side to keep it square, The best tool to use for that is bandsaw pro, press n for the dialoge box and you can adjust how close and how many cuts you want to make.

oDDity
06-07-2006, 05:49 PM
BTW, a good way for this particular problem would be this. IT keeps all quads and doesn't add much extra geometry.

etyrihje
06-07-2006, 06:40 PM
Thank you all for very useful inputs!
I will dive into the tutorials in "Inside LW 8", and he other hints and tips will be put on my mind as well, thanks!

hrgiger
06-07-2006, 07:29 PM
oDDity is right about making a square hole with a subpatch object. The only problem is, he assuming that the geometry you are creating the "hole" in is flat. This is why above I asked if the hull object you were trying to create is rounded. If it is, cutting with bandsaw will play h$ll with your overall form. It can be done, but it will require some serious tweaking.

Penforhire
06-07-2006, 09:49 PM
If your surface is not flat you can still use the Drill (stencil option) tool to maintain the base curvature but overlay new geometry easily along an axis. I thank Gerald Abraham's Digital Car Studio vid from Kurv for teaching me this one. You end up killing the polys and reconstructing to the new points you stenciled. That's how he adds stuff like headlights to smooth curving patched-spline panels.

oDDity
06-08-2006, 01:41 AM
The above example I gave still holds for cutting into a curved surface. Once you have the hole just select the inner loop of points, extend them and ctrl+v to line them with with the x or v axis, and you have a flat square attatched to a curved one in a second.

IMPERIAL
06-08-2006, 02:21 AM
or you can always start modeling from the holes. make the holes and then extend and weld or do whatever you do.

steamthunk
06-08-2006, 10:19 PM
Why wouldn't sub-patch weighting work?

oDDity
06-09-2006, 01:52 AM
Maybe it would, but I feel better using real modeling solutions. It makes the model portable, and it makes adjusment and additional geometry easier to add if needed. I don't know who can be bothered fiddling around with a paint tool.

SplineGod
06-10-2006, 04:25 AM
I have been using LW part time for three years, but I have mainly done buildings and architecture, using the basic shapes and my favorite tool the bolean tool...

I have barely scrathced the surface of subpatch modelling, I built a toon character, but subpatch modelling is so far from the other apporach, and keeps messing with my brain...

I want to build a large oil tanker (ship), and I can imagine how to get the main shape of the hull, but how do I make square holes in the hull, using bolean produces weird results...

What I am asking here I guess is to be pointed to a good crash-course in subpatch modeling... I have the "inside lightwave" books #7 & #8, any other sources that any of you would recommend?

Any hints and tips appreciated!

Thanks

Usually I only leave models in subpatch mode that will be deformed during animation in some way. You dont always have to stay in subpatch model while modeling. Some details can be done after youve modeled to a point with subpatches and then frozen back to polys.

I have some free tutorials on my site. Some show how to model with a variety of tools including subpatches. :)

hrgiger
06-10-2006, 01:07 PM
Subpatch weighting won't work because it will destory the curved surface you are trying to cut into. BTW, subpatch weighting is useless in most any other situation as well.

There is more reasons NOT to freeze a mesh other then whether or not it's going to be deformed. If you freeze the mesh, you lose the ability to change the resolution of that mesh in layout for rendering purposes.

pixelranger
06-10-2006, 03:05 PM
general advice: Stay as far away from the boolean tool as possible! It produces heaps of unmanagable geometry (tris and n-gons) and it certainly won't aid you in becoming a better modeler. Try using bevels, extrudes, "loop-tools", and the other tools at hand that let you keep control over the topology/geometry flow. The boolean operations absolutely have their place, but should be a last resort, when all else fails or if you're running out of time.
Best of luck!

SplineGod
06-10-2006, 03:44 PM
Lots of people use booleans and lots of people do hard surface modeling without even using subpatches. Some use splines to get a shape as well. The trick is to be careful and use a little bit of planning when using booleans or any other modeling techniques for that matter :)

hrgiger
06-10-2006, 07:03 PM
Booleans and subpatches don't have to be exclusive from one another. You can boolean an object that is to be subpatched, it just requires a little thought when creating your boolean cutting object.
Here's an old thread where I posted a mini-tut on cutting an object that you want to use with subpatches. It starts with post #20:

http://www.newtek.com/forums/showthread.php?t=11372&page=2&highlight=mosquito

I think if you have the option of keeping your mesh subpatched (and there is almost no case where you can't), you should. It leaves you with the most flexibility.

oDDity
06-10-2006, 11:48 PM
THe ony two reasons I can think of for working without subpatch, is if you're doing output that specifically requires polygonal meshes, such as a game engines, or it's a big, complex model and you want to keep it as light as possible, in that case use polygons if you can get away with it, and it certainly pays to know how to achieve good results using polygons and smoothing, becasue it is a different and sometimes trickier process than relying on subpatches, I've done a lot of modeling for games so I''m well aware of that.

SplineGod
06-11-2006, 01:07 AM
And you can be sure that objects like the Galactica arent subpatched. :)