Three ways of using Refine with animation, tried on the same dancing
character (LOD 4, about 6 % of the original triangles). Each worked; which one works best depends on
the character and the animation.
Tick the clips you want the LOD to hold up in, then Generate LODs. Refinement picks its
frames from what this step measured.
Select the level to optimise in the LOD table.
Note the maximum errors in the timeline legend, so you can compare. In this example, after
Generate LODs: 2.50 / 7.10 (surface / silhouette). Zoomed out, the legend shows the
maximum of the whole timeline.
Lock the vertical scale (the lock button above the timeline), so the curves keep the same scale while you
compare steps.
A. Automatic: the worst frames
Frame source: Auto (top-K worst frames), K 16, Surface budget 70 %, then
Refine with animation. Result: 1.68 / 4.08.
Changing K or the budget changes the result, and not always in the obvious direction — see
Examples & measurements. Refining takes seconds, so trying two or three values is
practical.
B. Evenly spread frames
Frame source: Uniform across clip, K 16. On this character: 1.79 / 5.00 —
a clear improvement over no refinement, but less than A. On a second character with a flatter error curve,
this option came out ahead (see A new character from scratch).
C. Peak by peak, with marked ranges
A more hands-on approach that puts you in charge of which poses count:
Set Frame source to From marked ranges.
In the timeline, find the highest peak and Ctrl+Shift+click it — a 3-frame range
is created around the local maximum.
Refine with animation. The marked peak comes down; another frame becomes the highest.
Mark that one too and refine again. Repeat a few times, noting the legend values. The small arrows under
the curves point at each curve's highest frame, which makes the next peak easy to find.
Step
Range added (frames)
Surface
Silhouette
after Generate
—
2.50
7.10
1
983–985
2.14
4.57
2
897–899
2.16
4.11
3
455–457
1.91
3.63
4
450–452
1.92
3.57
5
459–461
1.77
3.68
6
669–671
1.81
3.49
The first range did most of the work.
The values do not fall at every step: fixing one peak can let another frame get worse. Keep an eye on
the numbers and stop at a step you like.
After step 4 the highest silhouette frame was already inside a marked range, so marking it again would not
help. Steps 5 and 6 marked the highest surface peak instead (the green arrow).
The Ranges list shows the error inside each range, which helps to see which peaks
responded.
Side by side
Approach (same character, LOD 4)
Surface
Silhouette
No refinement
2.50
7.10
A. Auto, K 16
1.68
4.08
B. Uniform, K 16
1.79
5.00
C. Six marked ranges
1.81
3.49
On this character all three helped. A gave the lowest surface error, C the lowest silhouette error, at the
cost of a few minutes of work. Another character may rank them differently.
