to interact with double-buffering.
Use preload_pdyn() to precompute trees for each worldbundle.

Add new per-particle field, "ismember", to show escapees.

(Some "kira" commands use kira_set(), which already does this.
Just set "changed" for those which don't.)
Impose a max trail gap (delta time).  Break up trails at time-gaps
exceeding this threshold.

the kira-computed smoothed cluster center.

New "kira hrdiag" command allows turning it on/off, setting plot ranges.
"kira int x" is a synonym for "kira int x=x", the common case.
New "sqrtmass" attribute.  "mass" is again in linear, not log units.
Disable kira display if we don't get a valid input file.
XXX Bogusly import getfloats() from partibrains.c; should go in a separate
utility .c/.h file.

of picked stars.

dynamical->solar mass unit conversion.
If it knows, then "kira massscale" only allows user
to override if user-supplied value ends with "!",
e.g. "kira mscale 600!".

able to track collections rather than single particles (not yet though).
Trails are relative to tracked-point position, so can be non-inertial.

Compute fake aggregate temp/luminosity for CM nodes.
Oops, marks need their own sel[] array!
Allow adjusting H-R diagram alpha values too.

Pay attention to emph/see settings.
Get selection working properly.

Only use SEL_DEST-initialized pick etc. info.

Add set-selection features, including interaction tracing.

Hack for gcc 3.0's stdio (#ifdef NEWSTDIO).

rather than a string.

Star type is number-encoded, sigh:
	0 = unknown
	1 = ms	Main Sequence
	2 = cd	Compact Dwarf??
	3 = gs	??
	4 = bh	Black Hole
	5 = sg	Supergiant?
	6 = hb	Horizontal Branch

Now, the only #ifdef KIRA/WARP needed in partibrains.c are
the data-command initialization routines.  All others,
including control-command parsing and specialized drawing,
is now via a function table.

Add framework for incrementally reading paragraphs of input:
kira_open(), kira_read_more().
Add scraps for maintaining trails, but not enough to work yet.

(either before or after "kira" reader).

Oops, now kira_draw needs to ensure we really have something to draw!

OK, toss those extra 'break's.

Add "kira tree" support -- tree arcs, with crosswise tick-marks
at center-of-mass points.  Tickmarks lie in screen plane, with
length of <tickscale> times true separation.

Re-extract whenever kira_set changes something.
Add particle tracking.
Compute ring sizes correctly, and draw rounder rings.

Add ring markers for non-isolated stars.  Not finished yet, but seems usable.
No GUI yet, but new commands:
   kiractl nodes  {on|off|roots}
   kiractl rings  {on|off|roots}
   kiractl ringsize {sep|semi}   (ring size from curr. separation or semimajor axis)
   kiractl scale  <scalefactor>
   kiractl span   <minpixels> <maxpixels>   (allowed range of ring radii)

Change encoding of nclump: n for leaves, -n for center-of-mass nodes,
   so colormap can make them distinguishable.

Bug: after kiractl command, must change timestep before it takes effect.
Bug: ring markers aren't colored yet for some reason.