Give the aerodromes a colour of their own, and say what each aircraft is

Four things about the animated pictures, and the window kept in step with
them.

The aerodromes were amber, and so is an aeroplane at twelve thousand feet.
Sixteen units of CIELAB apart is not two colours, it is one: an aircraft low
over a field was drawn in the field's own colour and neither could be picked
out from the other.  They are magenta now, fifty-six units from the nearest
altitude colour, which is what the ramp leaves free once red, amber, green,
cyan and violet have gone on height -- and what an aeronautical chart marks
an aerodrome in anyway.  The test states that as the distance rather than as
the colour, so that changing the ramp cannot quietly walk an aircraft back
into the airports.

The height beside an aircraft was the flight level, which is shorter and is
what an aviator reads, but "376" is only a height to somebody who already
knows it is one.  It is feet with the unit on it now, rounded to the
twenty-five feet Mode S reports altitude in: a real reading is a multiple of
that and comes through untouched, while a moment interpolated between two
reports stops claiming to know the height to the foot.

The flag of the country of registration now comes off the address block
where no register answered.  Taking it from the register's answer alone left
the flag off exactly the aircraft that had nothing else beside them either.
Mexico was missing from the address table while we were in there, which a
receiver in the American southwest notices; two registers independently give
XA- registrations for that block.

And what sort of aircraft it is, which is two facts and not one.  What it is
comes off the air: every identification message carries three bits under its
type code saying whether it is light, large, heavy, a rotorcraft, a glider,
a drone or a van on the apron, and that is the only word about what an
aircraft *is* that needs no register.  They were being decoded and thrown
away.  They are inside the identification frame the log already writes down
in full, so every log this program has ever written has them, including the
ones written before anything here knew to look.

Whether it is military comes off no air at all -- a tanker calls itself
heavy exactly as an airliner does -- and is read from the address block
instead.  On one evening here AE07D3 broadcast "heavy" and sat in the United
States military block; the register, asked separately, came back with a
C-17A Globemaster III, tail 90-0534, United States Air Force.

Labels in an animation now behave as the boxes in the window do.  One keeps
its place for as long as that place still works and is moved only when
something takes it, which on a real log is about half as many moves as
deciding afresh every frame; the moves that are left are eased over half a
second of playback; and what the next label is laid out against is where a
moving one is going rather than where it has reached.  A still has no frame
before it and places its labels exactly as it always did.

The fading was only half done.  A label's name faded, because it is drawn in
the aircraft's own colour, but its rows and its flag were fixed colours and
stayed at full brightness -- so the brightest thing on that part of the
picture was the one aeroplane nothing had been heard from.  An indexed
picture cannot blend, so the row grey and all twelve flag colours now have
dimmed copies at each of the four fade steps, and the whole box goes
together.  A crowded frame, which drops back to the short label, drops the
class and the flag with it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016PsWPTweCT6pwxKngvVxcg

packaging/bandsaunter.1

@@ -1,5 +1,5 @@
 .\" Generated by packaging/make-man.py -- do not edit by hand.
-.TH BANDSAUNTER 1 "2026-09-04" "bandsaunter 2026-09-04_09" "User Commands"
+.TH BANDSAUNTER 1 "2026-09-04" "bandsaunter 2026-09-04_10" "User Commands"
 .SH NAME
 bandsaunter \- scan, record and identify radio signals with an RTL-SDR
 .SH SYNOPSIS
@@ -1329,6 +1329,21 @@ stretch one \[em] a route between two airports under their full names runs to
 sixty characters, and breaks at the arrow so that the two ends of the flight
 stay whole.
 .PP
+A box keeps its place for as long as that place still works and is moved only
+when an aircraft or another box genuinely takes it, which is about a third as
+many moves as laying every box out afresh each frame. The moves that are left
+are eased over about half a second rather than jumped, since a box that
+teleports reads as a different box, and the window redraws at thirty frames a
+second for as long as anything is moving and drops back to five when it
+stops. That is affordable because the ground is dimmed once and kept: cutting
+the view out of the fetched map and looking every level up in the palette is
+most of a tenth of a second over two megapixels, and nothing about it changes
+between frames unless the view, the window, the brightness or the map itself
+has. What the next box is laid out against is the place a moving box is
+going to, not the place it has reached, as otherwise its neighbours would
+move as well and move back when it arrived; and a box in motion is drawn over
+the ones standing still, so that it stays readable while it crosses them.
+.PP
 .B d
 cycles how much each box says, for a busy sky;
 .B t
@@ -1566,7 +1581,46 @@ between \[em] a receiver hears aircraft over its own county, and the county's
 airports say where on the map you are looking. They come from the same map
 data the tiles are drawn from, asked once per area and kept for a month.
 .B \-\-no\-airports
-turns that off.
+turns that off. They are drawn magenta, which nothing else on the picture is:
+the old amber sat sixteen units of CIELAB from the altitude ramp's yellow,
+which is to say it was the same colour, and an aeroplane low over a field was
+drawn in the field's own colour. The ramp already spends red, amber, green,
+cyan and violet on height; magenta is what it leaves free, and is what an
+aeronautical chart marks an aerodrome in anyway.
+.SS What is beside each aircraft
+Its height in feet with the unit on it, rounded to the twenty-five feet Mode S
+reports altitude in, so that a moment interpolated between two reports stops
+claiming to know the height to the foot; its speed; what sort of aircraft it
+is; its type and registration; and the two ends of the route, each with the
+flag of the country its airport is in. The country of registration gets a flag
+too, from the register where one answered and otherwise from the address
+block, so it is there for an aircraft no register has heard of.
+.PP
+What sort of aircraft it is comes from two places. Every identification
+message carries three bits under its type code saying what is transmitting
+\[em] light, small, large, high vortex, heavy, high performance, rotorcraft,
+and under another type code glider, airship, parachutist, ultralight, drone,
+spacecraft, or a vehicle on the ground \[em] and that is the only word about
+what an aircraft is that needs no register. Which list the three bits index
+depends on the type code, and zero means the aircraft declined to say, which
+is answered with nothing rather than a guess.
+.PP
+Whether it is military comes off no air at all, as no aircraft broadcasts it
+and a tanker calls itself heavy exactly as an airliner does. It is read from
+the address instead, since states set aside blocks of their national range for
+their armed forces. A state can fly a military aircraft on a civil address
+whenever it likes, so this finds nobody who does not want to be found, and the
+table holds the allocations a receiver in the ordinary world hears rather than
+every one that exists.
+.PP
+A label keeps its place for as long as that place still works and is moved
+only when something takes it, which is about half as many moves as deciding
+afresh every frame; the moves that are left are eased over about half a second
+of playback rather than jumped, and what the next label is laid out against is
+where a moving one is going rather than where it has reached. A still picture
+has no frame before it and places its labels exactly as it always did. The
+whole box fades with its aircraft: an indexed picture cannot blend, so the row
+grey and all twelve flag colours have dimmed copies at each fade step.
 .SH METERS AND SENSORS
 Two things on the ISM bands are worth naming rather than reporting as
 hexadecimal.