Cache what has been looked up, make it browsable, and say where this lives

Four things asked for in turn, landing together because they run through the
same files.

THE MAPS.  The tiles were already cached and always had been -- a second
evening on the same view was measured at nought network requests -- but the
work done on them was not.  Every window open decoded forty PNGs and resampled
a megapixel and a half into this program's own projection, for an answer that
cannot have changed, because a coastline does not move.  The finished map is
kept beside the tiles now: 0.61 seconds become 0.01, byte for byte identical,
two hundred kilobytes a view.  Both windows and both kinds of still picture get
it, all four reaching the ground through one function.  A map with squares
missing is deliberately not kept, since caching a hole would keep it for a
month and the point of calling a partial map provisional is that it is asked
for again.  And because this adds a disk consumer, the whole cache is now
pruned to four hundred megabytes, least recently *used* first: a tile fetched a
year ago and looked at last night is the receiver's own neighbourhood, and
discarding that to keep last week's holiday is the wrong way round.

THE LOOKUPS.  APRS and FT8 now ask who each station is licensed to.  Every
other mode that hears a callsign already did -- speech transcripts, Morse
idents, the recording browser -- and all five resolve through one file, so a
callsign heard on two bands is asked about once.  The rules for finding the
licensed callsign inside a heard one are now in one place rather than per band,
because getting them wrong is silent: a register asked about W1AW-9 returns
nothing, which looks exactly like a station that is not licensed.  An SSID, a
rover suffix, a guest prefix, a digipeater alias and an unspelled hash all come
off or are refused.

The bug worth recording is that the first cut of this did the lookups and threw
them away.  The book has to be told to save and was not, so every evening would
have asked the register about the same net again -- which is the one thing
caching them was for, and is invisible from inside a single run because the
answers are all in memory while it lasts.  Caught by looking at the file on
disk rather than at the display.  There is a test for each side of it now, and a
register of which modules resolve callsigns at all, which fails when a new one
starts so that somebody has to decide whether it should.

THE REGISTER.  c in saunterbrowse opens everything ever looked up: sixty-odd
callsigns and sixteen hundred aircraft here, every field of each in two columns
because a licence has a dozen and a screen is wider than it is tall.  tab
switches, / searches every field rather than the name -- the question is
usually "who was in Arizona" rather than "which callsign" -- and g opens the
place in a browser.  Only the coordinates go into that link: a map does not
need to be told whose licence it is looking at, and the link is the one part of
this that leaves the machine.  A headless box, which is the normal case for a
receiver, gets the coordinates printed instead.  Callsigns no register could
place are kept rather than dropped, because "asked about, and in no register
reachable from here" is a fact about a station.

THE FRONT OF IT.  A title screen for each program: five rows of blocks cut by
hand, a figlet dependency to draw eleven letters being the largest thing that
would then be in the requirements, coloured blue to red across the width, which
is the ramp every waterfall here already uses because it is what a spectrum
looks like.  The interesting part is where it does not appear -- everything
here can be piped into something else and a banner in the middle of that is
corruption rather than decoration, so anything that is not a terminal gets
nothing, --help is untouched because it is drawn after parsing, --no-splash
turns it off for a run and BANDSAUNTER_NO_SPLASH=1 for good.

And the address.  INSTALL.md said "git clone <the repository>" for a long time:
a placeholder in the first command anybody types, unnoticed because nothing
reads install instructions except somebody installing, who then cannot.  It is
filled in, along with the readme, the metadata, both manuals and the Homepage
field of all three packages.  The tile server's User-Agent pointed at a topic
listing on somebody else's site for want of an address of its own; the usage
policy of that service asks for one naming the application and giving somewhere
to look it up, so an operator with a question about the traffic has somebody to
ask, and now it gives the real one.  Seven tests so the placeholder cannot come
back, verified by putting it back and watching two of them fail.

One thing forced by all this: the keys page in saunterbrowse was exactly as
tall as an eighty-by-twenty-four terminal, so the register entry pushed "q
quit" off the bottom.  A test caught it.  Home and End have merged into the
Page Up line, which were always the same thought.

THE WINDOWS.  They open maximised now, this being a map and the thing anybody
wants more of being map; f goes to true full screen and back, and is written
along the top of the screen because a window with no frame is one somebody has
to know a key to get out of.  Maximised rather than frameless by default,
because the title bar is where the band and the frequency are written.

And a map made bigger now gets a sharper map, which it did not.  The window
only ever re-examined the ground when the view left the box that had been
fetched, so a window opened at its default size and taken to the whole screen
kept the map it started with until an aircraft wandered far enough to move it
-- on a quiet band, a long time to look at a blurred coastline.  Measured
before it was believed: 1100 to 1920 asked for nothing and stretched a
1364-pixel map across 1920, then across 3840.  It now compares map pixels per
degree in hand against what the view wants, and asks when it is being blown up
by more than fifteen per cent.

That comparison has to be per degree rather than pixel against pixel, which a
surviving mutation was what established: the fetched box is a quarter wider
than the view, so a map with exactly as many pixels as the window is wide has
only four fifths of them on the screen.  The two ways of measuring agree
everywhere except a narrow band, and the realistic case sits inside it.  There
is a test pinning that case now.  Asking is safe at any size, because the
request is keyed on the window's dimensions: once answered, nothing more is
asked, which is what stops a window larger than the tile budget can cover from
asking all evening.

The braille, while this was open.  The banners were blocks in capitals; they
are braille in mixed case, two dots wide and four tall to a character, which is
eight times the detail and is what makes room for two heights of letter at
once -- a five-row block font has no second height to spend, so the name came
out shouted.  Two attempts failed first: thin one-dot strokes came out as
confetti, because braille dots render as dots and a one-dot stroke reads as a
dotted line rather than a line.  What worked was cutting the font small, at cap
height seven where there is only one way to draw each letter, and doubling it.
Coloured deep blue through cyan to a cool white, which is deliberately not the
waterfall ramp the rest of the program draws in: that one has to run to red
because it stands in for a spectrum, and a title screen stands in for nothing.

One hundred and four new tests.  Full suite 2892 passed.  Built as
2026-09-24_01.

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

packaging/saunterbrowse.1

@@ -1,5 +1,5 @@
 .\" Generated by packaging/make-browse-man.py -- do not edit by hand.
-.TH SAUNTERBROWSE 1 "2026-09-04" "bandsaunter 2026-09-04_08" "User Commands"
+.TH SAUNTERBROWSE 1 "2026-09-24" "bandsaunter 2026-09-24_01" "User Commands"
 .SH NAME
 saunterbrowse \- read and listen to what a bandsaunter scan collected
 .SH SYNOPSIS
@@ -107,6 +107,12 @@ on it again. The frequency is written into your saved settings, the same list
 maintains, and takes effect on the next scan \[em] a scan already running read
 its settings when it started.
 .TP
+.B c
+Open the register: every callsign and every aircraft this installation has
+ever looked up, read back out of the two caches. See
+.B THE REGISTER
+below.
+.TP
 .B "? h"
 The list of keys, and which audio player was found.
 .TP
@@ -244,6 +250,61 @@ is written into the map: holding it and not saying so would be worse than
 either showing it or not asking for it.
 .B \-\-no\-lookup
 asks for none of it.
+.SH THE REGISTER
+.B c
+opens it.  Everything this installation has ever found out about a callsign or
+an aircraft, read back out of the two caches the lookups write: the scanner's
+identification, the Morse idents, APRS, FT8 and this browser all resolve
+callsigns into one file, and the aircraft side keeps its own.  Between them
+they are a record of who and what has been heard from this aerial, and until
+now the only way to read either was to open the JSON.
+.PP
+The list shows the callsign or registration, who or what it is, where, when it
+was looked up, and whether there is anywhere to point a map at.  Under it,
+everything known about whichever one is highlighted, in two columns \[em] a
+licence has a dozen fields and a screen is wider than it is tall.
+.TP
+.B "\[ua] \[da]"
+Move.  Page Up and Page Down go a screen at a time, Home and End to the ends.
+.TP
+.B tab
+Switch between callsigns and aircraft.
+.TP
+.B /
+Search.  Every field rather than the name, because the interesting question is
+usually not "which callsign" but "who was in Arizona" or "what Bombardiers
+have gone over", and both of those live in the detail.  Every word has to
+match, so a search can be narrowed.
+.TP
+.B g
+Open where this one is, in whatever browser the desktop uses.  Only the
+coordinates go into the link: a map does not need to be told whose licence it
+is looking at in order to show a place, and the link is the one part of this
+that leaves the machine.  Where nothing is known about the position it says so
+rather than guessing, and on a machine with no browser \[em] which is the
+normal case for a receiver \[em] it prints the coordinates instead.
+.TP
+.B r
+Read the caches again, for somebody who has just finished a scan in another
+window.
+.TP
+.B "c esc"
+Back to the recordings.
+.B q
+still quits.
+.PP
+Callsigns that no register could place are kept rather than dropped.  "Asked
+about, and in no register reachable from here" is a fact about a station, and a
+list that quietly dropped them would make an evening of unlisted foreign
+stations look like an evening when nothing was looked up.  An aircraft is put
+on the map at the airport its flight started from, labelled as such: this is a
+register of airframes rather than a position report, and the origin is the
+nearest true thing.
+.PP
+The addresses are licence records, public by law and already printed by
+.BR bandsaunter (1)
+in its own reports; this shows them the same way rather than more
+prominently.
 .SH THE MAP
 A licence says where its holder is, so a list of callsigns is also a map. The
 scanner writes one as it runs and
@@ -398,6 +459,30 @@ during the scan, and the
 .I _transcription.txt
 beside the recording is what a later re\-run wrote. The file wins, being the
 more recent of the two.
+.SH THE TITLE SCREEN
+Drawn on startup in braille, two dots wide and four tall to a character, which
+is eight times the detail a block gives and is what makes room for capitals and
+lowercase at the same height \[em] a five-row block font has no second height
+to spend, so the name comes out shouted. Coloured in a gradient from deep blue
+through cyan to a cool white across the width \[em] deliberately not the
+waterfall ramp the rest of the program draws in, which carries on through green
+and yellow to red because it stands in for a spectrum and has to mean
+something. Under it, who conceived the program and what wrote it.
+.PP
+The font is twelve letters cut by hand at cap height seven and then doubled,
+because a stroke two dots thick reads as a line where one dot thick reads as a
+dotted line.
+.PP
+It never appears where it would be in the way. Everything here can be piped
+into something else, and a banner in the middle of that is corruption rather
+than decoration, so anything that is not a terminal gets nothing at all. It is
+drawn after the arguments are parsed, so
+.B \-\-help
+and a bad argument say their piece without one over the top.
+.B \-\-no\-splash
+turns it off on a terminal too, and
+.B BANDSAUNTER_NO_SPLASH=1
+turns it off for good.
 .SH FILES
 .TP
 .I ~/bandsaunter/
@@ -481,6 +566,8 @@ or
 .UR https://www.gnu.org/licenses/
 .UE .
 There is no warranty, to the extent permitted by law.
+.SH HOMEPAGE
+.I https://frostwarning.com/git/dustcouncil/bandsaunter
 .SH BUGS
 The list is read when the browser opens.  Press
 .B r