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WeirdoStudio
10-13-2004, 07:24 AM
I'm making a character and i want to add things such as straps to hold his gear on, etc etc.. Is there away to do this easy? Is there away to add say a strap around his chest then with the use of a plugin or something be able to tighten that strap up so atleast it is close to his skin without manually moving every single point?

Crocodilian
10-13-2004, 11:26 AM
See SplineGod's tutorial:
http://www.3dtrainingonline.com/support/creating_armour.mov

very helpful. Although he's creating conforming armor for a torso, the basic technique applies to what you're doing.

The brief crib: select and copy the points from the base object , from which you want to create your attached object, paste them in a new layer, and then extrude or otherwise construct from said points.

An alternative, little used but powerful, technique is to define an lscript that builds your buckle or strap and then attach it a "powergon" script.

WeirdoStudio
10-13-2004, 11:32 AM
Hey thanks for the reply.. Your a little ahead of me when it comes to Lscripting, but i will give this method a shot.. Thanks

Fongool
10-13-2004, 07:46 PM
I've done this sort of thing quite a bit in recent weeks! What I end up doing is copying the geometry where I want the strap, pasteing it into a new layer, freezing and subdividing it (sometimes more than once if I need to) then I select the string of points that most closely define the path of the strap. Then I copy these points into a new layer, with the subdivided geometry in the BG layer, and I use MovePointOnBG to tune the line of polys (I have that plug mapped to "x" so I can quickly selcet a point, move it, drop the tool, select a new point by flipping between X and spacebar).

Then I select the points in order and create an open spline. Then I either use that spline for a rail extrude, or I run CurveToPlate on it to create the strap. If I use CurveToPlate, I'll have to manually select each pair of points and rotate them to get the face of the strap aligned correctly (curveToPlate has no way of knowing what you intended, it just creates a ribbon of quads to the width you specify, using the spline as it's centerline). It's a bit of work, but not too awful. Then I run Thickener2 or SuperShift to thicken it up. Here's some examples of things that I've done this way: Belt, thong straps, glove and boot seams, the thingy that the boot laces are attached to and the zipper. :D

Crocodilian
10-13-2004, 09:56 PM
Hey Fongool,

those are great thumbnails. You breezed through the steps a little quick-- would you explain in more detail?

MovePointonBG is at:
http://www.ribsngibs.com/pages/CG/plugins/plugins.html

but I couldn't find "CurvetoPlate" on Flay. . .where do you get it?

SplineGod
10-13-2004, 11:04 PM
I have a video tutorial on my site (the baseball one) that shows how to cut detail into an object, create splines from that and use those splines to add further details like the stitching and holes for the stitching. :)

Fongool
10-14-2004, 03:30 AM
Wow, how annoying that curve to plate doesn't show up on Flay! here's the link: http://www.studiohiro.com/

It's a pretty simple plugin, if you can't figure it out, just babelfish the online docs, it's really easy. Basically you just need an empty layer with a spline (or multiple splines) in the BG layer. You can tell it how wide you want the ribbon(s) to be and whether to make it flat or rise up in the center like a tent. It's great for making Anime character hair.

In the meantime, check out Larry's (SplineGod's) tutes, they're bound to be more useful than the desperate, clumsy noob techniques I cobbled together out of my tiny pool of knowlege. :)



Really my cheezy approach to seams and straps is no more complicated than what I said, it only seems glossed over because it's so simple. :) Trust me, it's WAY more complicated to explain than it is to do...

Here's the steps:

1. select the polygons you want the strap or seam to run across. Make sure to grab a little extra.

2. copy them

3. select an empty layer and paste the geometry

4. if it's sub-D's, freeze it. If the resulting geometry isn't dense enough (you kind of have to develop a sense of how much is enough) hit subdivide. You want a reasonably dense chunk of geometry here for two reasons, first, it'll give you more choices of points to select from to make your spline, and second, MovePointOnBG works better if your background geometry is more dense.

5. Now, on your frozen and possibly subdivided chunk of geometry, select a single line of points that will define the centerline of your strap or seam. If there aren't points *exactly* where you really want them, just select ones nearby, you'll be fixing it all up exactly the way you want in in a couple of steps from now.

6. copy the selected points and paste them into a new layer.

7. Make your dense chunk of geometry the background layer.

8. Switch on wireframe mode in the perspective window and use MovePointOnBG to slide the points around until you get the *exact* path you want for the strap.

(At this stage I also tend to delete many of the points to keep the resulting strap from getting too "wiggly". if it conforms too tightly, sometimes the resulting strap ends up too uneven and looks lumpy. Basically you want just barely enough geometry to follow the contours reasonably well. Again, with experience, you develop a sense of this.)

MovePOintOnBG can be really clunky to work with unless you set up a hotkey for it. Basically the process is: select a point, switch on MovePointOnBG, move the point, deselect the tool and the point, select another point and do it again. By assigning the plugin to my x key, I can quickly do this series of actions with two fingers by alternating between hitting x to activate the plugin and hitting the spacebar to drop the tool and deselect the point so I can move on to the next point. it's relatively painless if you do it that way, though it would be MUCH nicer if the tool worked like drag. But anyway...

9. Once you've massaged your line of points to perfection, select them in order and on the create tab select make curve > open curve (dunno what the shortcut is, I haven't memorized that one yet...)

10. Now, select an empty layer and put the layer with your spline in the background. At this point, I decide which will work better for what I'm trying to achieve, if I want a seam I'll create a small polygon (usually a hexagon or octogon) and I'll just rail extrude it. That's how I did the seams on the gloves and boots. If you chose to rail extrude, then you're done! Just sub-D that puppy and it should be pretty smooth! (you'll have to triple or delete the end polys unless you used a quad as your base extrude polygon)

11. If you wanted something flat, like a thong strap or a belt, rail extrude might still work for you, or you could try Curve To Plate. Again, with the spline in the background layer, start up the plugin and you'll get an interface where you can choose what surface gets applied to the resulting ribbon and how wide it will be and whether you want it flat or have an extra row of points down the center which can have a height amount added to it so it pokes up along it's centerline. Then just say OK and viola, a ribbon of single-sided quads is born.

12. Unless your spline is oriented straight up and down or side to side, the ribbon probably won't follow the contours very well. It's centerline will, but likely the ribbon itself will be half buried in your geometry. For example, the zipper I did worked flawlessly and no tuning was required. But the thong straps needed a lot of adjusting to get the ribbon to face out perpendicular from the body as it curled around the sides.

basically the way I adjust this is to select two points at a time and align the perspective view until I can get a clean rotation (generally looking straight down the centerline of the ribbon and putting the cursor directly between the two points) to rotate that one segment into correct orientation. Then I just move along to each pair of points and rotate them into aligment with the same technique.

Essentially what I'm saying is: if the ribbon doesn't follow the contours the way you want, you will have to manually adjust the points until it does. I use rotation on pairs of points so that the width of ribbon doesn't become inconsistant and make me have to kill myself.


13. Once you've done this, you can either just make the surface two-sided (that's what I did on the thong) and be done, or you can use Super Shift, Smooth Shift or Thickener2 to give the strap depth.


My technique gets pretty clumsy at this point because sometimes you have to move or scale the strap in order to get it to stick out from the surface the way you want. Like, with the zipper it wasn't an issue, I could just make the thing as thick as I needed until enough of it was sticking out from the shirt. But if you wanted to use this approach to say, put trim on a skirt, it could be tougher to get it the way you want without it poking through the inside of the skirt.

So I'd definitely research more intelligent methods of doing this before resorting to my tomfoolery. It's worked okay for me, but I can't promise it won't just make you look like an idiot. definitely don't do it while anyone is watching... :)



Oh, and to make the zipper, the only thing I did differently was to subdivide the ribbon once before Super Shifting it. Then I selected alternating polys on the face of the ribbon and super shifted them again to get the raised parts.

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