Failing to sleep...
It seems I go to bed, and the next thing I know I'm thinking about some clothing thing, and then I fail to fall asleep unless I successfully divert my thoughts elsewhere. (The other night I figured out how I wanted a waistcoat/blouse thing to look; at least I now know what I'm doing with that fabric so it isn't a somewhat boring camisole top.)
Last night I was thinking about seams in clothing, and how they would be modeled in a computer. Or rather, I was thinking about modeling clothes in a computer, and then realized clothes had seams, and my brain went 'Wait, how do you deal with that?'. And because I'm too lazy to look this up myself, and since I think that some of you may have more experience in this area, I'm asking LJ. If you happen to know of specific papers or other useful information, please point me to them.
So, the only time I've looked this stuff up before, was back a few years, when I took a graphics class. I was actually looking at how to get things like lace to show up lace-like (with light coming through the gaps) as my end project. In the process of gathering background papers to read, I came across a paper that was modeling a square piece of cloth, and showing how it would drape over a ball. (They were using a square of springs with one or two diagonal springs inside the square.) Since that wasn't my interest at the time, I filtered all other similar papers out of my search.
Since I didn't recall any papers with seams of cloth, I was trying to think of rendered clothing examples. The FF series clothing falls in the pasted on category. (The movie portions are probably fine, but mostly the costumes fall toward the fitted side so it doesn't matter.) Eternal Sonata is similar (Falsetto's tails drape out at a 30-45 degree angle; I'm not entirely sure if I can get that effect even with wire supports). Blue Dragon actually had clothes that draped; Kluke's skirt hem and Zolas tail swayed when they spun around. None of the clothing had any visible seams, not even as decorative features (and the shine on Kluke's dress makes me think of PVC). I expect movies would have better examples, but I haven't watched any recently enough to recall them (and I'm usually watching the movie rather than trying to figure out the costumes).
Technically, for movies they can simply create a piece of cloth molded to the shape they need. There is no need to worry about the limitation that currently in the real world cloth comes in flat sheets. To shape it, seams are used. I don't know what the state of CAD is with regards to fabrics; I'm guessing its a niche and there isn't a whole lot there. Or there isn't a whole lot in the 'here are the flat pieces that'll be cut out' and 'here is what it'll look like when sewn together'. At some point I'll actually look this stuff up for real. In any case, the point is, I can't think of existing examples of usage.
So, a somewhat simplified example, in a similar vein as draping a square piece of cloth over a ball. Suppose there is an upright cylinder, and somewhere on the side someone has taken an ice cream scoop out (so that it's concave) and then smoothed the edges around scoop. There is also a rectangle of fabric; the width is the height of the cylinder, and the length is approximately the circumference of the cylinder. It's a woven fabric, meaning there is no stretch along the straight of grain nor the cross grain (parallel to the length and width of the rectangle), but there is some stretch along the diagonal if put under stress. At the two ends of this rectangle the edges are cut so that they form a smooth concave arc. These ends are then sewn together. This means that at regular intervals the fabric is essentially attached, but between these points the fabric could separate some (if you yank on a longer length stitched seam with loose weave fabric, it'll pucker). This tube of fabric is then placed on the cylinder (or the fabric is sewn after being wrapped around the cylinder if you're being picky about the middle of the tube now being smaller than the top of the cylinder). The upper edge of the tube is attached to the top edge of the cylinder, and the seam is placed over the concave section of the cylinder. And then the fabric hangs there. And how will it hang differently if additional weight is added to the lower edge of the fabric tube.
Anyway, I feel like someone out there ought to have already figured out how to model and render this. If not, I'm going to be disappointed.
Last night I was thinking about seams in clothing, and how they would be modeled in a computer. Or rather, I was thinking about modeling clothes in a computer, and then realized clothes had seams, and my brain went 'Wait, how do you deal with that?'. And because I'm too lazy to look this up myself, and since I think that some of you may have more experience in this area, I'm asking LJ. If you happen to know of specific papers or other useful information, please point me to them.
So, the only time I've looked this stuff up before, was back a few years, when I took a graphics class. I was actually looking at how to get things like lace to show up lace-like (with light coming through the gaps) as my end project. In the process of gathering background papers to read, I came across a paper that was modeling a square piece of cloth, and showing how it would drape over a ball. (They were using a square of springs with one or two diagonal springs inside the square.) Since that wasn't my interest at the time, I filtered all other similar papers out of my search.
Since I didn't recall any papers with seams of cloth, I was trying to think of rendered clothing examples. The FF series clothing falls in the pasted on category. (The movie portions are probably fine, but mostly the costumes fall toward the fitted side so it doesn't matter.) Eternal Sonata is similar (Falsetto's tails drape out at a 30-45 degree angle; I'm not entirely sure if I can get that effect even with wire supports). Blue Dragon actually had clothes that draped; Kluke's skirt hem and Zolas tail swayed when they spun around. None of the clothing had any visible seams, not even as decorative features (and the shine on Kluke's dress makes me think of PVC). I expect movies would have better examples, but I haven't watched any recently enough to recall them (and I'm usually watching the movie rather than trying to figure out the costumes).
Technically, for movies they can simply create a piece of cloth molded to the shape they need. There is no need to worry about the limitation that currently in the real world cloth comes in flat sheets. To shape it, seams are used. I don't know what the state of CAD is with regards to fabrics; I'm guessing its a niche and there isn't a whole lot there. Or there isn't a whole lot in the 'here are the flat pieces that'll be cut out' and 'here is what it'll look like when sewn together'. At some point I'll actually look this stuff up for real. In any case, the point is, I can't think of existing examples of usage.
So, a somewhat simplified example, in a similar vein as draping a square piece of cloth over a ball. Suppose there is an upright cylinder, and somewhere on the side someone has taken an ice cream scoop out (so that it's concave) and then smoothed the edges around scoop. There is also a rectangle of fabric; the width is the height of the cylinder, and the length is approximately the circumference of the cylinder. It's a woven fabric, meaning there is no stretch along the straight of grain nor the cross grain (parallel to the length and width of the rectangle), but there is some stretch along the diagonal if put under stress. At the two ends of this rectangle the edges are cut so that they form a smooth concave arc. These ends are then sewn together. This means that at regular intervals the fabric is essentially attached, but between these points the fabric could separate some (if you yank on a longer length stitched seam with loose weave fabric, it'll pucker). This tube of fabric is then placed on the cylinder (or the fabric is sewn after being wrapped around the cylinder if you're being picky about the middle of the tube now being smaller than the top of the cylinder). The upper edge of the tube is attached to the top edge of the cylinder, and the seam is placed over the concave section of the cylinder. And then the fabric hangs there. And how will it hang differently if additional weight is added to the lower edge of the fabric tube.
Anyway, I feel like someone out there ought to have already figured out how to model and render this. If not, I'm going to be disappointed.