mlandis@nmsu.csnet (05/19/88)
I have a few questions concerning anim recording and playback, and thought I might find a few opinions here :-). I created BoingThrows (Fred Fish #134) with Eric Graham's dilbm, pilbm, and movie programs. It is a 50 frame animation that only contains 39 unique pictures. This is possible because dilbm can create a delta file that is reversible. For instance, to do the dribble only required 4 unique pictures: ball at top of dribble, just leaving the hand, almosty to the floor, and hitting the floor. Four delta files were all that I needed to create the downward motion, and then by reversing these delta files the upward motion was created. This means that for movie to show all 13 frames necessary for 2 dribbles (or any number of dribbles for that matter), all I needed was 4 delta files. This fact is what kept the movie file short enough to be run on a 512K machine. Another place I use this feature is when Amiguy misses a free throw (Yes the basketball player on Fred's disks is not a perfect free throw shooter, he misses every 37th shot), I just have the ball bounce off the back of the rim and return to his hands along the same path it was shot. This is what leads me to my questions. I would like to make Amiguy miss randomly, not just every so many shots. This random capability does not exist with dilbm and pilbm. I thought I would be able to do this with The Director, if I could just get my animation in the proper anim format. Well I just got GrabAnim the other day and thought this could solve the anim format problem and it did. However, to get the same animation with random misses, the only way I could think of to do it increased the size of the animation tremendously. With Grabanim I had to create 5 different anim files: DownBounce, UpBounce, Shot, Miss, BallReturn. Then with Director I was able to write a script that randomly showed the Miss anim in place of the BallReturn anim. Well this is quite a waste because UpBounce is just a reverse of DownBounce, and Miss just a reverse of Shot. So finally for my questions: is there a program available that create anim formats compatible with the Director, that allow the deltas to be reversed similar to dilbm and pilbm? (I looked through the anim specs some, and it looks like the XOR capability is what is needed?) If there is such a program, I could not see a way Director could take advantage of reverse playback, it looks as if the anim command always generates the next successive frame, no way to go backwards. Is this correct, is there a trick fro doing this with Director? I would really like to keep the size of the anim so it will still run on a 512K machine, but don't see how unless these type of capabilities exist. (Will the new version of Videoscape allow me to do this, I'm still waiting for my upgrade). If you would like, e-mail responses directly to me, and I'll post a summary to the net. Thanks for any help you can provide. Marvin Landis (mlandis@nmsu.edu) or (mcsmal@nmsuvm1.bitnet)