CompuServe Thread

#Animating a glacier

13 messages in this thread
#152021From: Ian ChristieFeb 9, 1995 4:37 PM
I have a job to animate a glacier retreating over a landscape. If anyone has any tips or thoughts on the subject I'd love to hear them. Ian.
#152051From: Kyle J. McKisicFeb 9, 1995 7:51 PM
Hi Ian, can you be more specific as to how it should move, or what parts of the scene have to change when it moves? etc… -Kyle
#152076From: Ian ChristieFeb 9, 1995 10:21 PM
Kyle, We're talking end of the last ice age. The ice is receding back to the north To be honest I'm not sure that the ice itself actually moves or it just melts back like a sort of receding hairline. I'll have to consult the geologist on that one. I guess I'd hoped that someone on ASOFT had tackled a similar situation. My first thought was to create morph objects. But it has occured to me to try BonesPro to manipulate a mesh. Ian.
#152206From: Kyle J. McKisicFeb 10, 1995 10:48 AM
Ian, I just did something that I think is similar to the effect that you're trying to get. I had to make a car form out of the street – where the street starts to bulge as it looks like something is pushing itself up. the amorphous from then slowly constrains itself to the shape of the car. what I did was use the SEEZ_I.IXP routine (avail in the ipas lib) to create a 8 bit zbuffer image of the car – so the high points are white, and the low points are black. then, I used the image as a displacement map on a grid, that I applied SKIN to. voila! perfect match to the car geometry. I also took the image into Photoshop and created some blurred copies to use as intermediate morph targets before I arrive at the refined shape. It worked out really well. I could send you (or upload) a flic of it if you're interesed. -Kyle
#152222From: Yost GroupFeb 10, 1995 12:01 PM
Very very creative use of SEEZ, Displace and Skin, Kyle. I'd love to see the flic, if it's not too large to upload to the DL's. – G
#152232From: Kyle J. McKisicFeb 10, 1995 12:36 PM
Gary, I'm finalizing it right now, I do a procedural wipe with opacity/bump maps to get rid of the street and reveal the car underneath. I'll upload it soon -Kyle
#152332From: Ian ChristieFeb 10, 1995 6:13 PM
Kyle- sounds very interesting- I'd love to see it.
#152488From: Larry MintonFeb 11, 1995 9:19 PM
It would be a receding hairline look, with a lots of chunks left behind half-buried in the ground. These chunks would melt and form ponds. Also, there is a lot of garbage pushed to the front of the glacier – large boulders, gravel, etc. As the glacier stops advancing, this material is dumped and forms morains. Technically speaking, the glacier doesn't move back or even stop moving, it just melts faster than it moves forward. LAM (grew up near Morain, Ohio, where the last big glacier ended)
#152638From: Ian ChristieFeb 12, 1995 5:46 PM
re: glacier animation. Thanks, I'm beginning to gat a handle on this. Iaqn.
#152088From: John K. JordanFeb 9, 1995 11:36 PM
>>glacier retreating… First, I would ask how does a glacier retreat? Does it retreat by slowly melting just at the leading edge, or more likely, by overall melting, sublimating, and settling over a wide area? Given a fairly hilly terrain (i.e., just been scarred by a glacier!), I would try modeling a single (fairly organic) sloped glacier mass protruding into the valleys from beneath the terrain mesh. (Use Displace and perhaps fractalize or a good bump map?) To make it move, my first thought would be to make a copy or two for morph targets, then manually distort the morph targets with a little vertex editing near the front (retreating) edges of the ice mass. Perhaps gradually lowering the sloped glacier mass while morphing would give the appearance of a retreating glacier. But then again, maybe not. <g> JKJ
#152333From: Ian ChristieFeb 10, 1995 6:16 PM
Re: glacier animating. Thanks for your input. Yes, I think I've got to consult the geologist about the nature of this sort of glacier movement. I don't think that is like the frozen rivers that flow from mountains.
#152346From: Kyle J. McKisicFeb 10, 1995 7:17 PM
Ian, I'm putting some finishing touches on it this weekend, I'll put it up on monday. -Kyle
#154167From: Bjorn j. WestergardFeb 18, 1995 10:19 PM
I've animated the tide rising with a glass block being pushed through the valley… sounds the same. My frien d Jim Stipes of Univ. of Washington State did an award winning movie on earth formations/glaciers etc.