wizard@sosaria.UUCP (Chris Brand) (09/20/89)
What is the easiest way to produce a proper looking free fall with keyframe animation in Sculpt Animate 4D (or 3D)? When I use global animation, I can set up a spline and let the points distribute themselves on the path using the speed slider so that it looks like a free fall. However, this fails when I'm using keyframe animation, and I have to do it, since the ball that falls down is supposed to contract and hop up again, this time to a point lower than the starting point (naturally). I don't think that can be done in global animation, can it? -- ---------------------------------------- Chris Brand - wizard@sosaria.ccs.imp.com "Justice is the possession and doing of what one is entitled to" - Platon ----------------------------------------
stan@teroach.UUCP (Stan Fisher) (09/25/89)
In article <0160.AA0160@sosaria> wizard@sosaria.ccs.imp.com writes: > >What is the easiest way to produce a proper looking free fall with keyframe >animation in Sculpt Animate 4D (or 3D)? >---------------------------------------- >Chris Brand - wizard@sosaria.ccs.imp.com >"Justice is the possession and doing >of what one is entitled to" - Platon >---------------------------------------- If the falling object is be the 'key framed' object you're gonna have to save many key frames with the position set appropriately in each, even then the motion will 'step' in speed as each key frame is reached. If you can use a combination of key frame and 'global' methods to achieve your effect and use the global for the falling objects path, the fall can accelerate smoothly. What I've done is to select 'add circle' and specify 4 times as many divisions as you want for path positions. Then select only 3/4 of the circle, leaving the verticies from 9:00 to 12:00 deselected. Erase the selected verticies. Now you have a 90 degree arc containing the number of verticies that you want positions for. Now do 'expand/contract' and turn off the height direction (probably Up/Down) and click contract several times. This will leave you with a vertical line made up of verticies that have separations ranging from very close together at the top to far apart (relatively) at the bottom. Make that a Path and select the direction. If you want 'bounce' then do the same as above, but make a half-circle and only twice as many divisions in the circle as you want path positions for. Delete only vertices from just after 3:00 to just before 9:00, and then do the contract. Stan Fisher - stan@teroach.phx.mcd.mot.com - asuvax!mcdphx!teroach!stan Motorola Microcomputer Division, Tempe, Arizona - Voice (602) 438-3228 Call our User Group BBS "M.E.C.C.A." running Atredes 1.1 @ (602) 893-0804
mlandis@nmsu.edu (Marvin Landis) (09/26/89)
In article <0160.AA0160@sosaria> Chris Brand (wizard@sosaria.UUCP) asks: > What is the easiest way to produce a proper looking free fall with > keyframe animation in Sculpt Animate 4D (or 3D)? You will need to use several keyframes for the ball to drop, and then again for the ball to rise. In the simple diagram below, I am assuming there is the same number of frames between each keyframe: o Position of the ball in keyframe 1 o Position in keyframe 5 (Maybe a little overlap with position in 1) o Position in keyframe 9 o Position in keyframe 13 o Position as it hits the ground in keyframe 17 --------------- As the diagram shows, just position the ball closer to its previous position when the ball is moving slowly at the top of its bounce, and farther from its previous position when its moving faster. Of course with keyframes you can squash and stretch the ball in appropriate positions to achieve the effect you desire. You might even be able to use the spline idea to help determine where the best positions are for the ball in each keyframe, just create the spline and use it as a "template" to manually position the ball in each key frame instead of letting SA do it automatically. As for the problem you are having with "Not enough memory" errors, if I recall correctly that is what happens if you are running Morerows on your system disk. If that is the case, get rid of morerows and see what happens Marvin Landis mlandis@nmsu.edu
mlandis@nmsu.edu (Marvin Landis) (09/26/89)
After my last posting on this subject, I realized I made a small mistake in my diagram if you want to do squash and stretch. Then Stan Fisher pointed out that "steps" would occur in the animation using my method, so I thought I would post a second message and clear a few things up. (And anyway I wasn't listed on the latest Bandwidth Waster's Hall of Fame and I felt really left out :-) First, I should have stressed the use of squash and stretch more in my original posting. Yes, there would be steps in the speed of the ball using the keyframes as I described, however if the ball is stretched in each keyframe as it falls, I feel the illusion created is good enough you cannot detect this "stepping". I admit it is still not an exact imitation of a falling ball, but its easy and I have done a bouncing ball animation using this method its practically impossible to see the stepping in speed. So here's the new diagram, with one new keyframe necessary for squash and stretch: o Keyframe 1 o Keyframe 5 (still no stretch) o Keyframe 9 (stretch the ball a small amount) o Keyframe 13 (stretched some more) O Keyframe 17 (stretched to its maximum) This is the frame I forgot. o Keyframe 18 (squashed as it hits the groud) ---------- Try it, I think you'll find that since the ball changes shape each frame, this helps cover the stepping speeds problem. After all its easy, and its all an illusion anyway :-) Marvin Landis mlandis@nmsu.edu
pawn@wpi.wpi.edu (Kevin Goroway) (09/27/89)
In article <330@opus.NMSU.EDU> mlandis@opus.UUCP (Marvin Landis) writes: >In article <0160.AA0160@sosaria> Chris Brand (wizard@sosaria.UUCP) asks: > >> What is the easiest way to produce a proper looking free fall with >> keyframe animation in Sculpt Animate 4D (or 3D)? > >You will need to use several keyframes for the ball to drop, and then again >for the ball to rise. In the simple diagram below, I am assuming there is >the same number of frames between each keyframe: [nice little picture deleted] I find that if I add a circle, and then cut it in half (leaving only the top half) I end up with a nice path for a bouncing ball... You can duplicate it and shrink it as you like. (this can be used to make the ball appear as if it is losing energy) This would be the global approach, but there is nothing stopping you from adding a few key frames where you need them, to change the shape of the ball while it is moving. >Marvin Landis >mlandis@nmsu.edu -- +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+= | Worcester Polytechnic Institute | "It happens sometimes, people just | | Pawn@wpi.wpi.edu Pawn@wpi.bitnet | explode, natural causes."-Repo Man | +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=
DAVID_LYNN_BRUMFIELD@cup.portal.com (09/28/89)
Use a Spline with 2 knots at the extream ends. Adjust the knot Speed at the
top end of the spline so the vertices are closer to the top than the bottom.
Remember the approximate distance you move the slider to the left or right.
Now adjust the Slope to give the Spline a more gentle curve. Go to the Lower
knot and adjust the Knot speed slider in the opposite direction and the same
length from the center as you did the top knot. This will give you evenly spac
verticies from one knot to the other. If you don't change the speed on both,
the spacing will only change to the half way between the knots. The next part
is harder. That is to get the Squashing effect. I like to use the Cycle object
method as seen in the "chip" (henry?) animation on the data disks. Make a
different version of your ball in steps of squashedness. Name them as the Manu
tells you, with numbers, to get the proper degree squished ball at the particu
frame you need it. This may seem like a very complex way to do this animation,
but it is much easier to adjust the single squished balls one at a time seprat
than to try to adjust the Key frames and get into the horrible cycle of having
fix your next frame because you just "fixed" the one before it! Read the text
file that came with Henry. It will help you understand how to do this type
of animation. Another good thing about doing it this way, is the Spline can
also be a path at the same time and by moving the knots only you can determine
where the ball comes from and where it lands very simply!! Sculpt 4D is THE
most powerfull animation program I use.
David B.