hi letterworks (and everyone else),

I’m tied up all the time, reviewing magz, keeping my website uptodate, learning Poser, doing stills, doing animation, doing tutorials and doing Rendo as well. No sweat, it’s just; what to do first.

I render the animation out overnight, there is still lots of room for improvement but it gives you some idea. Project 011 Scene 02 (these moves, this gown, 18 sec from 286 in total) Take (=version) 12. At first I had to get the lighting right (IDL didn’t work out, I invented softboxes etc), then make the moves, then conforming clothes didn’t work out, then dynamics showed all issues nanette is running into as well.

I found out that conquering Cloth Room is: take another perspective. While Pose Room – conforming clothes included – is anything Virtual, Cloth Room is everything Reality. 

Pose Room is everything about morph-dial and bone-driven mesh deformation without any link to reality. You can have a rope standing up and have Vicky walk right onto it to the top. You can conform figures A to B, which means that they share the same morph and bone drivers, and that the B-ones are master. So people conform clothes to Vicky, pose Vicky, and take a shot. But they also could had clothes conform to Vicky conform to a skeleton, and pose the skeleton. Or, conform the skeleton to Vicky conform to clothes, and pose the clothes.  It’s in the naming too. If a table has its legs named as a horse you can make it gallup just from your pose library. If the horse, or the table, has the legs named as Vicky you can make them wear jeanz, and walk in them. If you really take care, you can have the table wear jeanz and gallup at the same time, point and click.

I’m referring to this as people demand cloth room to recognize conforming clothes for further processing. Poser only recognizes bone-driven meshes and calls them figures. Non-bone-driven meshes are props. We regognize figures as clothes, beings, vehicles, buildings, gnarly trees, whatever. Poser doen’t. Skeleton conformed to Vicky conformed to Jeanz. Is Vicky clothes? How can Poser know?

Cloth Room is Reality. It has gravity and air. 

Take a piece of cloth, pump up the density (increase mass), zero the air-resistance to eliminate the air-effects, drop it from some height and look up your first class highschool mechanics formulas, and the Earth gravitational constant. They apply (with a quirk. Tell me which).  Check whether your animation speed is 30 fps, and you can predict when the thing hits the floor. Density is kg per m2. Office paper is 0,080, is on the package (80 grams it’s called, per m2 that is. A0 flipover/poster size is 1 m2). I’m a 6 feet guy , I guess my pants take about 1 m2 of cloth, when I put them on a kitchen scale it reads say 250 grams, so the Poser setting would be 0,250. Just measure up your own clothes, and you know.  

Air resistance is similar.  It’s the force generated by an air flow of 1 m/s through (or at) a 1 m2 cloth surface. You can measure it. Take a cylinder (Poser primitive), make it long enough, put it horizontal als a flag pole, and attach a piece of cloth. Just collide to the pole, and one row of vertices in the constraints group. Now you’ve got a flag. Drape it, after some frames it will hang down properly. Now you can apply wind force, from the menu, make it from aside. The wind will blow it aside, gravity will pull it down and the angle that results from the simulation tells you the relationship. Vary resistence and density and the angle will exactly vary as expected. 

Now redo the first experiment, take the cloth up but now you give it meaningful density and air resistance values. Like the default ones, which are for table cloth. Drop it, and note that it takes a bit longer to hit the floor. If you drop it from larger heights, and note the intermediate results, you can observe that it reaches a constant velocity going down. The cloth moves through the air, the resistance generates a force upward. Gravity pulls it down, and increses the velocity. Therefore, the air resistance force will increase, until it equals gravity. Then the forces are in equilibrium, and the thing will not accelerate any more. Just another way of deriving the air resistance value.

Under water, some cloth absorbs water and becomes heavy. Increase density a lot. All cloth will resist water far more than air. Increase ‘air’ resistance a manyfold. Apply the ‘wind’force generators at will. Now you’re into fluid mechanics, and able to dress up your mermaids.

Are cloth parameters weird and at magic scales? No, they’re right from the physics book, in standard physics units. Something with force per m2 in most cases. 

How many frames does one need to settle a piece? Like life, it depends on density and air resistance. Large density and low resistance will speed things up, as thing will come down faster. And vice versa.  

More on this tomorrow, the animation is still rendering and I’ll have to walk the dogs.

By the way, this was not about theory, This was about me discovering Cloth Room. It’s not Virtual, it’s Reality. For me this implies that when I get weird results, it’s either in the simulation algorithm, or in the interpretation of reality. I do need a proper understanding of reallife cloth, to bring Cloth Room to life.

In Pose Room, I am boss. In Cloth Room, reality is.  For some, Pose Room and Cloth Room are both about clothes, and one is an advanced case of another. For Poser, Poser Room is about figures, and just for me: some figures are clothes. For Poser, Cloth Room is about cloth simulation, and just for me: some cloth are clothes. I know about clothes, Poser doen’t at all.

For me, Dynamic Clothes relate to Conforming Clothes as a formula 1 car relates to a bike. Both have two pedals, gear switching in the steering wheel, sporty clothes are handy and for both a helmet is required. Both have their use, and Ferrari (read: SM) is not going to build a “ F1-car for bikers”, and a handy “F1 dashboard wizard” will never happen, I guess. I would appreciate it, but we have to learn to live without, I’m afraid. Sorry.

Till then, we’ll have to experiment, to find out, to share. This was my attempt, for today. 

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Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though