Movie format could save space

The movies are using the snapshot format, which includes all of the ring info. In the ring info, the rotation and shift deltas and the HLS color are not used at all during movie playback. These attributes constitute 40 bytes out of 120, or one third of the total size of the ring structure. The actual savings could be nearly a third, since most of the space in a movie is taken up by rings (hundreds of rings per frame).

The savings would require adding a second serialization method, e.g. MiniSerialize, which would be used by the SnapMovie object. The method could be optimized by placing the deltas and the HLS color at the start of the ring structure, because then it would still be possible to do a single write directly from the ring, instead of copying to an intermediate structure first.

A problem with this approach is that it would longer be possible to export a complete (non-mini) snapshot from a movie, since some of the information would be missing. The HLS color could be restored from RGB, but not the deltas. On the other hand the deltas aren't useful in snapshots so maybe it wouldn't matter.

NOTE that WinZip reduces Steve1.whm by 61%, and Steve2.whm by 73%.

Space-saving benchmarks:

60 seconds, 25 FPS, default speed, window maximized but not full-screen, wait for full ring count before starting to record, sizes in MB, ring counts are rough averages

patch           rings   old     new     less
kaleid          1000    172.5   108.8   37%
pinwheel        500     98.0    62.5    36%
lotus light     300     71.4    46.5    35%
cross           150     34.6    26.3    24%

useful nugget of ring conversion code:

nr.RotDelta = rp.RotDelta;
nr.ShiftDelta = rp.ShiftDelta;
nr.Hue = rp.Hue;
nr.Lightness = rp.Lightness;
nr.Saturation = rp.Saturation;
nr.Rot = rp.Rot;
nr.Steps = rp.Steps;
nr.Scale = rp.Scale;
nr.Shift = rp.Shift;
nr.StarRatio = rp.StarRatio;
nr.Sides = rp.Sides;
nr.Delete = rp.Delete;
nr.Reverse = rp.Reverse;
nr.Color = rp.Color;
nr.Pinwheel = rp.Pinwheel;
nr.LineWidth = rp.LineWidth;
nr.DrawMode = rp.DrawMode;
nr.Spacing = rp.Spacing;