I have been pulling what hair I have out over this one for the past couple of years. Doing a little issue house keeping and was wondering if the best and brightest here might be able to help me out.
I would like to do a ken burns type effect on panning over an image where you specify two or more points on the image, and the camera smoothly moves from one point to another in an smooth curve, not a straight line from point to point.
I had created a system that would create a curve using splines in a 100 X 100 box and then the app would scan the line and use that as a reference to the percentage difference in XY to position the center of the view. But it only works for moves of 100 frames or less and I need it to be parametric for any feasible distance from point 1 to point 2.
OpenInventor and VRML98 (as applied in cosmo worlds the ill-fated vrml editor) used a system where you would have key frames; a specified set of floats that would be within a range (0.0 to 100.0) representing the percentage of transit of each key frame in the animation.
Let us say 3 points, [a:0.0, b:45.0, c:100.0]
You would then apply translations, rotations or whatever to each of these points. We will just apply a point in 2D space to each of these locations.
[a:[0.0,point(120,240)], b:[45.0,point(600,440)], c:[100.0,point(1200,500)]]
Then you could assign a curve calculation (tangent type) to the animation and the system would spit out a set of frames based upon a total time for the transit and the frame rate for the time.
transitTime = 30 -- seconds
frameRate = 15 -- fps
tangent = #hermite -- hermite or linear
The next challenge is to add acceleration and deceleration into the mix, but that is another problem entirely.
My big problem is in applying the curve calculations. Not being big on the whole trig-calc thing puts me at a distinct disadvantage. (Kids listen: math does add up in the long run).
Any thoughts?
Thanks, Nat
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