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Costanel
02-25-2007, 02:23 PM
Hi there,

I've modelled quite a lot of things(as well organic, as architectial), but I've had one problem lately.
Although I know how to create curves rails and roads, I always find it hard to make the distances equal, without dramatic polygon counts or some distortion.

For example: I tried to make a curved pipe(subpatched) and create a chair out of it. Problem is, it's very hard to edit while making te pipes equal in size.

What would be the best/easiest way to create it, and be able the modify it?

hrgiger
02-25-2007, 02:40 PM
Best way to create, you might want to try spline patching. It's the easiest way to control how much geometry is created and gives you precise results.

Modifying it, use modelers modify tools. I have found the move tool using falloff is quite useful. I used it recently to create an overpass making it gradually deline with some ease out. Used the bend tool (which isn't always the most intuitive to curve it to the right.

ercaxus
02-25-2007, 11:35 PM
You can try hairblade plugin. It acts a little weird sometimes but it can be useful for pipes and stuff.

It gives you control over the rotation and subdivision level of individual control points. You can create custom profiles and morph between them (same point count for both shapes).

I haven't been able to mirror a hairblade curve succesfully though. After the mirror the curve's point order(which means the curve itself) changes. I am almost sure (too lazy to check now) you can even send it to layout without freezing it.

Give it a try and good luck :D

THREEL
02-26-2007, 06:47 AM
Hi there,

I've modelled quite a lot of things(as well organic, as architectial), but I've had one problem lately.
Although I know how to create curves rails and roads, I always find it hard to make the distances equal, without dramatic polygon counts or some distortion.

For example: I tried to make a curved pipe(subpatched) and create a chair out of it. Problem is, it's very hard to edit while making te pipes equal in size.

What would be the best/easiest way to create it, and be able the modify it?

Hi Costanel,

When it comes to rails and roads, I would suggest making equal sections, like the kind you'll find in model railroading and childrens' electric race tracks. Then you can lay your sections end-to-end to come up with a design. You should be able to merge the sections together from there. Maybe you could research both the RR and road design, because I'm sure they have certain specifications of widths and lengths, especially when it comes to curved sections.

Take a look at the screengrab that I've included, and let me know if this is what your talking about. For these legs, I made a long 6 sided disc, you can go this low when your going to subpatch. Then, I made 6 sections toward the top with the bandsaw pro command. From there, I hi-lighted those top 6 sections and bent them 90 degrees with the bend command. One thing you have to remember with the bend command is to bend your selection in the right window. Once your in the right window, if you find your polygons bending from the wrong end, just "flip" the view. For example: if your bending in the top view, and it's bending from the wrong end, just change the view to bottom. Just make sure the bend is in the intended direction, because sometimes it's easy to get off the intended bend path.

Once I got 1 leg looking the way I wanted it to, I used the clone command to clone the object in a circular array. 3 clones at a 90 degree haeding with a center of X: 0, Y: 0, Z: 0

Hope this helps.

tHREEL, but you can call me AL.

THREEL
02-26-2007, 06:50 AM
Sorry, I forgot to attach the screengrab.

Here it is.

Tiger
02-26-2007, 09:47 AM
Morph!

Costanel
02-26-2007, 02:14 PM
Well, I'm trying Rope Editor Plus and Hairblade now.
I really like how these programs work, because they are easy to edit afterwards. Just drag points and the poly's follow.

I found out that Rope Editor Plus can make pipes as well, just create a rope with 1 strand, and remove the twitching. When I removed the first and last poly and ran Thickener, I had perfect pipes.

But is there any way to make a long road, inc. trottoir, without to much effort?
Hairblade could work, but it's a bit unwieldy for this.

omeone
02-26-2007, 04:17 PM
What's the project Constanel?
Do you have CAD 2D plans at least? even better 3D CAD models...

otherwise this is going to be ... awkward.

If this is for a real-world project, I can help you. I've done many in the past and have worked as a road and rail alignment engineer.

It all depends on the level of accuracy you need. One thing that will take some of the pain away is LWCAD - do you have it?

Costanel
02-27-2007, 02:53 PM
Yep, I've been combining LWCAD 2.1-splines with the LW-curves for a while now.

I found out that with using the LWCad splines, converting it to Lw-curves and using Hairblade on it works very well. This creates roads that are editable after they've been placed.
Profiler works very well too, but doesn't give the freedom of poly-count and shape HairBlade gives.

It took some getting used to, but combining these really is handy.
The model isn't perfect. But nevertheless made the attached model in < 5 min. It features only 432 poly's, and with HairBlade I could easily make the straight track only 1 extrusion and the curves 5+.
(the straight curves have been moved afterwards, this explains the bad lining).

I'm planning on doing some Cad-work, but haven't got any assignments atm.
The problem wasn't the modeling itself, but the polycounts which generally become a bother. But this method really makes it easy to keep this low.

Thanks for the tips!

Sande
02-27-2007, 03:13 PM
Profiler works very well too, but doesn't give the freedom of poly-count and shape HairBlade gives.


Have you tweaked rail curve/shape curve maximum freezing error when using LWCAD's profiler? I use profiler for low poly work from time to time and these give pretty nice control over polycount. :)

omeone
02-27-2007, 03:19 PM
It would be better to put a few divisions on straight track, it helps the renderer. 5+ division for most curves will be fine, once sub-patched - although be wary you maintain dimensions after the patches are turned on. For example maintaining rail guage through curves with patches will require extra polys.

Ordinary CAD might not bring you any advantages - only Alignment CAD (MX) will give you Dutch and European transitions, but I doubt you'll need this level of accuracy. (know anyone in TU Delft?)

If you are planning on any low-angle shots, super-elevation will be vital, on both road and rail.