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david_scotland
12-30-2009, 11:42 AM
I've been learning LightWave 9.6 for about six months and really enjoy modelling with it. I want to model a train and have a detailed blueprint for a train bogie with lots of components. To start me off, I've been following a tutorial where someone is using LightWave 8.5 to model a small spaceship. I reckon that the techniques used in the video will help me to model a train bogie. But the tutorial does not use sub-d surfaces at all. Does 8.5 not have any sub-d modes or is it better to model non-organic things without sub-d?

Here is an image of the bogie:

geothefaust
12-30-2009, 11:50 AM
LW8.5 does have SubDs, just hit your TAB key and it will be activated. You can edit the current objects SubD level by hitting your "O" key, and adjusting it there.

As for whether or not to even model it with SubDs....

That is entirely up to you. But, I what I would do is use a mixture of SubDs and straight polys. Each piece will be better to make or look better with a particular type. So play it by ear on a piece by piece basis. Also, keep in mind that you can model portions in SubDs and then freeze it to get normal polys by hitting "CTRL+D", again, play it by ear on a ratio of what seems to work/look best.

melmoth2
12-30-2009, 02:34 PM
I've been learning LightWave 9.6 for about six months and really enjoy modelling with it. I want to model a train and have a detailed blueprint for a train bogie with lots of components. To start me off, I've been following a tutorial where someone is using LightWave 8.5 to model a small spaceship. I reckon that the techniques used in the video will help me to model a train bogie. But the tutorial does not use sub-d surfaces at all. Does 8.5 not have any sub-d modes or is it better to model non-organic things without sub-d?

Here is an image of the bogie:

Looking at the schematic, I'm not sure you need Sub-Ds - you could probably model most of it using standard polys with rounding at the corners and edges. That way you would keep your poly count lower.

SplineGod
12-30-2009, 05:26 PM
I agree about using both where it makes sense to. I sometimes will also model some parts using splines as well depending on the part.

JeffrySG
12-30-2009, 06:35 PM
You might want to have a look at some of my subd/subpatch videos too if you're just getting started with them. Link in my sig. :)

david_scotland
12-31-2009, 02:31 AM
You might want to have a look at some of my subd/subpatch videos too if you're just getting started with them. Link in my sig. :)

Already watch all your videos and learned a lot from them, thanks.

david_scotland
12-31-2009, 02:32 AM
LW8.5 does have SubDs, just hit your TAB key and it will be activated. You can edit the current objects SubD level by hitting your "O" key, and adjusting it there.

As for whether or not to even model it with SubDs....

That is entirely up to you. But, I what I would do is use a mixture of SubDs and straight polys. Each piece will be better to make or look better with a particular type. So play it by ear on a piece by piece basis. Also, keep in mind that you can model portions in SubDs and then freeze it to get normal polys by hitting "CTRL+D", again, play it by ear on a ratio of what seems to work/look best.

Thanks. It's good to get a helpful steer in the right direction.

david_scotland
12-31-2009, 02:34 AM
Looking at the schematic, I'm not sure you need Sub-Ds - you could probably model most of it using standard polys with rounding at the corners and edges. That way you would keep your poly count lower.

Thanks, I'll have a go and hopefully I my enthusiasm will last forever.

Surrealist.
12-31-2009, 04:48 AM
For much of it, I think subd's make a lot of sense.

The problem with poly modeling when you have a lot of rounded and complicated surfaces, you wind up using a lot of segments to get rounded edges like on a disc object for instance. Then the more complicated angles beg for problems with non planar polys that you have to triple to render correctly. Then you have the complication of smoothing. The more complex the model the more time you'll spend with smoothing angles and other fixes.

SubD's remove these practical issues. I would model in SubD until I found a part that was was a no brainer to do as a poly object.

david_scotland
12-31-2009, 04:52 AM
I agree about using both where it makes sense to. I sometimes will also model some parts using splines as well depending on the part.

I like using splines, but I get a problem when I try to add points to a spline. Here are some images that show before and after adding a point to a spline. I get a new spline coming out of the end of the original spline. I can't figure out the reason for this.

david_scotland
12-31-2009, 08:19 AM
For much of it, I think subd's make a lot of sense.

The problem with poly modeling when you have a lot of rounded and complicated surfaces, you wind up using a lot of segments to get rounded edges like on a disc object for instance. Then the more complicated angles beg for problems with non planar polys that you have to triple to render correctly. Then you have the complication of smoothing. The more complex the model the more time you'll spend with smoothing angles and other fixes.

SubD's remove these practical issues. I would model in SubD until I found a part that was was a no brainer to do as a poly object.

Thanks for this.

Surrealist.
12-31-2009, 11:33 AM
No Problem.

Spline Modeling in LW is a polygon method of modeling. You can convert them to spline patches for one, or extrude them and so on.

I am not sure what is happening when you add a point, but it does look like it is starting a new spline from the last spline.

I think some tutorials on spline patching would be good idea if you want to use them. Try to google that.

hrgiger
01-01-2010, 08:41 AM
I like using splines, but I get a problem when I try to add points to a spline. Here are some images that show before and after adding a point to a spline. I get a new spline coming out of the end of the original spline. I can't figure out the reason for this.

Switch over to point mode and make sure you don't have any points selected before trying to add new points to a spline. It won't work properly if you do.

david_scotland
01-01-2010, 09:05 AM
Switch over to point mode and make sure you don't have any points selected before trying to add new points to a spline. It won't work properly if you do.

I tried that and still get the same problem. I have LWCAD installed so I can use LWCAD curves instead.

hrgiger
01-01-2010, 09:43 AM
Actually, I don't think you can. If you're using a recent version of LWCAD, it uses true NURBS curves which won't work with spline patching. I've seen the error you're getting before, I just remember why that is happening. Try killing your spline (k), reselect all the points in order and make your spline again (ctrl-p I think). Now try adding a point to it and see if that works. Make sure when you select all your points that you count them as you do and make sure its the same number that shows in the selection number. If you have more, you may have a duplicate point which you can then merge.

david_scotland
01-01-2010, 11:09 AM
Actually, I don't think you can. If you're using a recent version of LWCAD, it uses true NURBS curves which won't work with spline patching. I've seen the error you're getting before, I just remember why that is happening. Try killing your spline (k), reselect all the points in order and make your spline again (ctrl-p I think). Now try adding a point to it and see if that works. Make sure when you select all your points that you count them as you do and make sure its the same number that shows in the selection number. If you have more, you may have a duplicate point which you can then merge.

I'll try that the next time it happens. It's stopped doing it for now.

In LWCAD 3.0, you can draw several curves and convert them to LW curves and then patch them. I've tried it and it works.

hrgiger
01-01-2010, 11:31 AM
Yes, I suppose you could convert them. It seems like a lot of work in the end if you have a lot of patching to do but hey if it works for you. But it's rare that I get that error in building patches.

SplineGod
01-01-2010, 02:50 PM
I like using splines, but I get a problem when I try to add points to a spline. Here are some images that show before and after adding a point to a spline. I get a new spline coming out of the end of the original spline. I can't figure out the reason for this.

Make sure theres no points selected along the spline when you start to add points.
Also make sure that what you think is a single spline
already isnt a double spline. Sometimes the error doesnt
show up until you go to add points.
Make sure when you select one spline to add points to that the selection indicator shows that only one spline is selected.
Sometimes Ill build spline cages off template polys like circles of various sizes or off existing geometry.

Another option for microbevels etc is to use Dponts edge bevel shader included in his free DPKit.