CompuServe Messages

Hi George, Your question is similar to the following answer provided by Rolf… << How can I use tempo to be a certin spot at a certain velocity? >> Answer: First, set up the path as you would expect (probably with a key at points A, B, and C). Make sure there are plenty of frames in the animation (path), scale time if necessary. Go into TEMPO and enter the velocity curve editor. Set the velocity curve to be flat at 55 mph for the entire animation. Click OK to apply it (make sure fit to path is NOT on). Now go into the preview dialog to see at which frame the car passes point B. We'll call this frame f. Now go back into the velocity editor and set the start of the active segment to frame f and place a node there at 55mph (Make sure the end of the segment is the last frame). Add another node somewhere between the previous node and the last node at 45mph. Switch edit mode to 'Move Point' and click on the node you just made. Now what you want to do is move this node horizontally (leaving it 45 mph) to get the 'New Track Length' to equal the 'Original Track Length'. When you get it, click OK. Again, make sure 'Auto Fit To Track On Exit' is OFF. That should do it. Another approach is to actually figure out the time it would take to travel the remaining distance, BC. If your velocity is going to be linear across BC then your average velocity is (55mph + 45mph)/2 or 50mph. The distance from B to C can be found by setting the active segment in the edit velocity dialog to start at the frame that B is on and end on the last frame. It is then the value labeled 'Original Track Length', call it d. The time, t, then is just d miles / 50 mph = t hours. You want this in frames so convert the hours to seconds and then multiply by your frame rate. To find the frame to place the third node at, add your result to f. If you still have problems, make sure 1) you have plenty of extra frames. Add a whole bunch of frames, you can delete the excess when you finish. 2) The path is actually created to scale. 3DS doesn't have a unit setting for miles so set units to feet and make sure the path is actually the right length.