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Schwyhart
04-05-2017, 09:14 AM
I'm trying to model a keyhole, as shown in the image below.
I did a boolean operation on a cylinder and a mesh in the shape of the keyhole. It ended up very messy and it doesn't subdivide very well with either Subpatch or Catmull-Clark...even after I cleaned it up a bit.

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hypersuperduper
04-05-2017, 09:23 AM
Booleans and subdivision surfaces is a match made in hell. You will rarely get something that subdivides well after a Boolean operation, the amount you need to clean it up makes is easier to just model it directly.

Reco
04-05-2017, 10:42 AM
Make the shape of the hole and bevel it sidewise. Delete the key hole shape.
Make a circle and bevel it to the side. Make connections between the two.

Take a look at this video. It is 3DS Max, but you can use the same technique in Lightwave
https://www.youtube.com/watch?v=iEpGJTSZjS8


Simple illustration.
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Reco

prometheus
04-05-2017, 11:25 AM
if your goal is to do model excercise, then you got something to practice at, if your goal is to just render it out, simply mefaform divide it enough and run booleans instead ..set a proper shading smoothing angle and render away.

Schwyhart
04-05-2017, 12:52 PM
I continued with the booleaned version.
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squarewulf
04-05-2017, 01:06 PM
I continued with the booleaned version.
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That looks about how I'd build it. I'd say you've nailed it.

Edit: you could merge some of those tri's into quads to keep it cleaner and more lightweight.

Schwyhart
04-05-2017, 02:32 PM
Is this normal behavior for LW?
**Look at the wireframe vs the Subd mesh.
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kopperdrake
04-05-2017, 02:40 PM
Unless you've overlaid two screenshots together, I'd say you've got a sub-D version with the normals pointing inwards so we can't see the faces, just the wires, and you've got a polygonal version with faces pointing outwards. To make matters harder it might even be that the points are welded. If you hit the tab key, what does that look like?

Oedo 808
04-05-2017, 03:20 PM
How many Subpatch Divisions have you got it set at in the General Options?

prometheus
04-06-2017, 02:53 AM
I suspect that when you do hard surface items like this, which may require facet/bevel corner and proper shading smoothing set, it would be wiser to not use subdivision surface mode..., if you do use it, I would say you need to make sure that all edges around the drilled part is even, otherwise you will get uggly smoothing shading, even if it is in subdivision mode.

another tip, you may want to look up 3rd powers boolean tools, though I would suspect modoīs metafusion would be ideal for stuff like this, if you are keen to look that way.

hrgiger
04-06-2017, 09:08 AM
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For a flat shape like this as in the front face of a keylock where everything is flat around the keyhole, the only thing that matters is having a loop around the hole and a loop around the edge of the lock device itself. Everything in between can be connected anyway you want, its not going to matter on a flat surface. Boolean way to go is fine and sometimes the mess you have to clean up isn't too bad but I find it easier for this particular shape to start with the hole shape itself and work outwards much like the way Reco suggested. The other important thing is to not have to end up having to add edges to the outside shape and have to destroy the evenly spaced edges and the resulting roundness.

rustythe1
04-06-2017, 10:47 AM
if you want to create subdivision Booleans, get matamesh from 3rd powers, its amazing for that sort of thing, you can Boolean several subdivision objects and control sharpness of the join, and also add weld seams

Schwyhart
04-06-2017, 02:36 PM
Is this normal behavior for LW?
**Look at the wireframe vs the Subd mesh.
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I switched to CC and everything appeared correctly. I looked at the stats and nothing looked out of place.
I did notice on another mesh I'm working on, that I have a bunch of 1 sided (2 point) polys. I could only select it in polygon mode, not edge mode. I deleted them and all is good, but I wonder how that happened in the first place.

Schwyhart
04-06-2017, 02:41 PM
if you want to create subdivision Booleans, get matamesh from 3rd powers, its amazing for that sort of thing, you can Boolean several subdivision objects and control sharpness of the join, and also add weld seams

I'm holding off on most plugins until Next releases. I'm also tight on money and have a baby on the way...so my only option is to use native LW and a few free scripts.
Also, I am still getting acclimated to LW and don't want to install a bunch of random scripts. It's hard to know what is needed or not at this point in my learning.

djwaterman
04-06-2017, 04:18 PM
You don't need the paid plugins, a number of free one are all you need, LW modeler can do it all you just have to get your skills up with subdivision modeling, and you already got close. Keep your money for the time being.

shrox
04-06-2017, 06:59 PM
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For a flat shape like this as in the front face of a keylock where everything is flat around the keyhole, the only thing that matters is having a loop around the hole and a loop around the edge of the lock device itself. Everything in between can be connected anyway you want, its not going to matter on a flat surface. Boolean way to go is fine and sometimes the mess you have to clean up isn't too bad but I find it easier for this particular shape to start with the hole shape itself and work outwards much like the way Reco suggested. The other important thing is to not have to end up having to add edges to the outside shape and have to destroy the evenly spaced edges and the resulting roundness.

I concur.

prometheus
04-08-2017, 03:02 AM
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For a flat shape like this as in the front face of a keylock where everything is flat around the keyhole, the only thing that matters is having a loop around the hole and a loop around the edge of the lock device itself. Everything in between can be connected anyway you want, its not going to matter on a flat surface. Boolean way to go is fine and sometimes the mess you have to clean up isn't too bad but I find it easier for this particular shape to start with the hole shape itself and work outwards much like the way Reco suggested. The other important thing is to not have to end up having to add edges to the outside shape and have to destroy the evenly spaced edges and the resulting roundness.


not..sure, but some keyhole parts may have slightly curved surface where the hole is made, and in such case it would be more challenging and what you say above about how things are connected wouldnīt be valid ..for such case that is, otherwise it is correct.

gerry_g
04-08-2017, 05:44 AM
by having a loop around the edge you effectively offset the tension on the angled edge to the next loop out which is a big help with lessening the problems of pinch and stretch lines in a sub D mesh, the loop also gives you standard quad arrangement that works better for any bevel you may want to add on the outermost edge of the loop. What trigger is suggesting is standard good work practice and though some programs do incredible booleans these days (Lightwave excepted) it still the best way to go IMHO

hrgiger
04-08-2017, 10:48 AM
not..sure, but some keyhole parts may have slightly curved surface where the hole is made, and in such case it would be more challenging and what you say above about how things are connected wouldnīt be valid ..for such case that is, otherwise it is correct.

That is true, cutting a hole in a curved surface is more challenging especially if the hole has any sharp angles which would require more edges running into a single area which could alter the overall contour of the subdivision. In these cases, usually more geometry is required to minimize distortion. I would mention it might be a case for edge weighting with cc subdivision but in LW I wouldn't recommend using them. These days, there are far easier ways to do these things, either with mesh fusion or dynamesh.

Reco
04-08-2017, 01:11 PM
not..sure, but some keyhole parts may have slightly curved surface where the hole is made, and in such case it would be more challenging and what you say above about how things are connected wouldnīt be valid ..for such case that is, otherwise it is correct.

I was of the impression that Schwyhart model this keyhole as some kind of subdivision modeling training. In that case, it is
wise to leave the curved surface out, until you get the experience needed.

But if you check the link I posted, you can see how Arrimus 3D solved the curved surface problem. 20:30 It is still
simple. It is only a slot, and it’s done using boolean, and added the surrounding edged afterwards.

A keyhole shape as seen on the image plus a partial curved surface is a very difficult task.

There are tons of modelling tutorials on YouTube, but I'm using books on my hand when I'm updating my 3D skills. I have almost all Lightwave books available, and quite a few regarding 3D in general. This book is absolute my favorite when it comes to 3D modeling, And I will highly recommend it, even if you prefer YouTube or other video training source.
https://www.amazon.com/Digital-Modeling-William-Vaughan/dp/0321700899/ref=sr_1_1?s=books&ie=UTF8&qid=1491677858&sr=1-1&keywords=3d+modelling

Reco

Schwyhart
04-08-2017, 10:33 PM
It is kind of a modeling exercise. I had thought about modeling the hole itself, then adding a cylinder with the right amount of sides. Then connecting the two.
I got it eventually using the boolean method.
I have 3D Coat, but haven't used it much. I might try to do the same model in it just to learn some basics.
I also looked at MOI since it uses nurbs and could most likely handle this model fairly easily, so I downloaded the trial. Didn't get too far with it though because I ran into a few roadblocks. Doesn't seem like it's worth as much as it costs.

Either way, I did get it. When I have more time to do 3D, I'll get back to it. I've been busy working on TEDx stuff.

Surrealist.
04-08-2017, 10:48 PM
I only use Boolean when I need the odd angles to intersect that are impossible to do manually. Curved surfaces are a good example. And then I only consider the Boolean as a way to establish intersecting points. I then clean up and retopologize by hand to get the subD flow I want. This is why these plugins are so valuable as time savers. Doing it by hand is tedious. But for flat surfaces I will use other primitives to create the shapes or (parts of it and connect) on a flat plane as hrgiger suggests. I find this the fastest method.