2e9cb9af7e2bff55dc4e2f43fb725294e501f8ca
223
Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 Anachronaut
|
7e82b64d47 |
A dock that slides into line, and settles squarely on the port
Two things, and the second is the one that was actually wrong. The lander is slid into place at half a pixel a frame rather than put there. A dock is allowed eight pixels out in either direction, so snapping moved it a whole tile in a single frame - a jump, at the very moment the player was being told they had been careful. The worst gap closes in about half a second, which reads as the two of them settling together. And it settles SQUARELY now. It used to come to rest four pixels out however carefully it was flown, because the lander is drawn from half a screen less half a tile - which is what centres an eight pixel lander on the middle - while the station was drawn from half a screen exactly, so its left edge sat where the lander's centre was. Both come off the same origin now, and a gap of nothing puts one exactly above the other. stationGap is factored out along the way. Three callers wanted it: the one that draws the station, the one that decides whether it can be docked with, and now the one that slides the lander in under it. The sideways ease goes through that wrapped gap rather than the raw positions, because a dock made either side of the moon's seam has a raw difference of most of a moon. ---- And the fixtures moved to frame 400 ---- A dock waits to be told its message has been read, and reading a state file costs a disk read, so a placed run starts a good deal later than a plain one. The acknowledgement was at frame 100 and stopped working the day the state file arrived: the program had not reached the dock yet and the press went by unheard, which shows up as every sprite missing and reads like a drawing bug. Everything after it is sampled well clear of both ends. Two checks, each seen to fail on its own break - the alignment settles at 4,-8 without the shared origin, and the slide reads 0,-8 the whole way without the easing. Which of the two axes each one actually watches is written down beside them, because it is not the one you would guess. |
||
|
Anachronaut
|
1928275f87 |
A state can be placed, which four things were queued behind
Lander reads sixteen bytes from /lander.state if the disk has one and starts from those: position, velocity, where the station is, fuel, and which screen to be in. A disk without the file is the game as it always was, which is every other flight in the suite. It exists because some states cannot be flown to. A successful dock needs the lander alongside the station and matched, and NINETY SIX pad files failed to get there - not for want of trying, but because climbing spends sideways speed, so a lander cannot rise while matched and arrives slower than orbital every time. Reaching it wants two burns and a phase. The orbit check had already been deleted for the same reason, and the strike check was flown on a nineteen frame window, which is the sort of fixture that ends up measuring the boot time rather than the physics. Binary, because that is what a file is on this machine. A tool to build one from readable text is a small job for another day; until then the tests write the bytes with the fields named, which reads plainly enough. ---- The buffer is a whole block, and that is not caution ---- osFileRead lands a file in Data Memory and a file is stored in blocks of 256, so reading sixteen bytes into sixteen bytes of room writes over whatever follows. It did: the first version put the buffer in front of the view tables, and the program read its state, wiped the numbers every gauge draws from, and left immediately - "finished" and back to the prompt, with nothing on the screen to say why. Four checks, each seen to fail on its own break: a state file places the lander (row 192 and twelve cells of gauge, against thirty one with no file), a matched approach docks and is paid once and not once a frame, it then rides the station a tile under it, and the same approach unmatched is a wreck. The flown strike fixture and its narrow window are gone. |
||
|
Anachronaut
|
804dd3040e |
Docking, and a ceiling that is no longer the old screen's edge
The station can be docked with: close enough, and slow enough RELATIVE TO IT, or it is a wreck. Its speed is orbital speed, which is what the marks on the drift bar point at, so the instrument for this was on the screen before there was anything to dock with. A dock pays eighty units of fuel, once and not once a frame, and holds the lander a tile under the station until a thruster lets go - checked before the speeds are put back, or a burn would be wiped on the frame it was made and the lander could never leave. ---- And the ceiling went up, which is what made it work ---- Sixty four pixels was the whole of the sky a forty column screen had over the world's origin. It was never a fact about the world, it was a fact about the view, and the wide one starts twenty four rows higher: a lander stopped at the old line was stopped a long way short of the top of its own picture for no reason it could see. It is 192 pixels now, the top of the wide view. The station went from four rows up to twelve - about two thirds of the way from the ground to the ceiling. At four it sat exactly where anything climbing away from the surface had to pass, and being run down there is not a hazard, it is a toll: ELEVEN of this suite's flights were being run down as collateral, including the ceiling check, which has to climb past it to reach the ceiling at all. Moving both fixed all eleven at once. The height bar divides by sixty four rather than thirty two, because the band it describes is 368 pixels now and half a pixel of bar to a pixel of sky would stand 184 tall and run off the top of the forty column screen it is drawn beside. ---- What is checked, and what is written down instead ---- The wreck is flown. The fixture is narrow - the window measured 496 to 514 frames of climb and it sits at 505 - and that is said in place, along with the instruction to re-measure before believing the code is broken. It was not always narrow: at the old altitude any climb from 135 to 300 frames struck. Narrow is the right way round, because it means the station is hard to blunder into. The successful dock is NOT flown, and ninety six pad files failed to find it. That is not the search's fault: climbing spends sideways speed, so a lander cannot rise while matched. It is measured working instead - tank 100 to 180, message up, and the pair holding together one tile apart for two hundred and forty frames. |
||
|
Anachronaut
|
922511c8a7 |
A retro thruster, at half the strength of the one that lifts
Arresting a rise meant a sideways burn and a wait for the orbit to come back round. That is how a rendezvous really is flown and it is a lot to ask of somebody who has not flown one before, so down now makes the correction directly. HALF THE STRENGTH, deliberately: one sixteenth a tick against two, which is exactly gravity's own step. So it can stop a climb and it can hurry a descent, and it can never turn a landing approach into a crash faster than simply letting go would - the cheap way out of a mistake stays the expensive one. Four against eight on a keyboard, which is the same ratio. It does NOTHING to a lander on the ground, and that guard is load bearing rather than tidy. touchdown has already had its say and returns early once a lander is down, so there is nothing underneath to stop it and no crash to say it happened: measured without the guard, holding it drives the lander clean off the picture and spends a fifth of the tank doing it. ---- And the fixture that hid all of that ---- The first version of the landed check passed just as happily with the guard deleted, and the reason is worth writing down. A lander that has landed WAITS to be told its message has been read, and the keyboard fixture pads with NULs, which are not keys. So the program sat in that loop for ever and the picture was frozen at the moment of touchdown - every thruster held afterwards did nothing, which reads exactly like a working guard. The pad now presses A to get past the wait before the check tests anything, and both the row AND the fuel are read, because an engine that fired and moved nothing would keep the row and one that moved the lander for free would keep the fuel. The altitude bar check upstream leans on that same freeze for its stable end, and its comment said "stays landed" when what it means is "is not running any more". Corrected, because that is the sort of comment that sends the next person looking in the wrong place. |
||
|
Anachronaut
|
800f555ffb |
A station in orbit, going round and not yet dockable
S1 of the station: it exists, it orbits, it wraps, it is drawn. Docking is deliberately not here - the point of stopping at this rung is to fly up and find out whether matching a four pixel a frame target feels good before any rules are written about what happens when you reach it. IT NEEDS NO PHYSICS OF ITS OWN. A body at 64 sixteenths is exactly what a circular orbit is under the rules already here: the pull and the swing cancel at that speed at ANY height, because gravity never falls off and the moon is a cylinder that does not rotate. So the station is a position, a constant, and the same fourteen bit wrap the lander uses. That also means there is no prograde or retrograde to choose - nothing privileges a direction, which is what makes a second station going the other way a thing that can exist later. Four rows above the world's origin: off the top of a forty column screen and comfortably inside a wide one, so it is somewhere to go that the zoom is needed to see. It starts half a moon away and a lap is 256 frames, a little over four seconds, so it has to be found but will not stay lost. Its column is the middle of the screen plus how far round it is from the lander, wrapped to fourteen bits - which measures the long way round whenever it is behind, so anything past the half way point becomes a negative offset instead. Off the edge needs no test at all: a sprite's X is signed and sixteen bits, so a station three hundred pixels to the left is asked for at minus a hundred and forty and the device declines. Blue, and that is not taste. White is counted to find the ceiling warning, cyan to find the landing pads, magenta is the instruments and yellow is the lander. Blue is the one ink no check measures, and picking a measured one has broken a test twice already. toPixelsSigned is factored out of showLander, since the station wants the same sign-extended conversion. Four checks, each seen to fail on its own break. Measured going round at 244 pixels in sixty frames, off the far side of the moon, and back on the other edge. |
||
|
Anachronaut
|
32559ce872 |
The room a zoom buys goes to the sky, not to the moon
Zooming out drew fifty rows DOWN from the world's origin, which put exactly the same sky on the screen as before with twice as much moon under it. Measured: 47 per cent rock zoomed in and 71 per cent zoomed out. A zoom that shows you more of the thing you cannot fly through is not worth a button. The eighty column screen is fifty rows and the flyable band is thirty - the ceiling is eight rows above the origin and the deepest valley is twenty two below it - so the twenty rows a zoom buys have to go somewhere. They go above. The wide view starts twenty four rows over the origin, the ground sits near the bottom, and the whole band is on the screen: 23 per cent rock instead of 71. Which needed three things. The moon is drawn from row minus twenty four rather than from nought, because rows above the origin are sky by definition and because whatever the shell left in them is otherwise still there. The row origin comes out of the view block like every other screen number. And the lander's own Y moves with the view, which meant making toPixels' answer SIGNED at last: it masks to twelve bits, so a lander above the origin came back as a large positive number rather than a small negative one - harmless while such a lander was off the picture either way, and wrong the moment the view moved up to include it. That is the point of the button. A lander at the ceiling is off the top of a forty column screen, which is where the orbit lives and why the altitude bar had to exist; zoomed out it is at row 149 and you can watch the whole orbit. Four checks, and the proportion is deliberately not on its own: measured alone it passes for a moon floating over a void, because pointing the view back at the origin leaves the rows under the terrain simply never drawn, and black counts as sky. Both breaks that matter went straight through it. What catches them is that the ground has to reach the bottom of the screen and the sky has to be empty - the latter only on a shell scrolled a hundred and eighteen lines deep, since that is what it takes to get anything into the rows the wide view moves into. The tap fixture also moved to frame 100. Fifty rows of moon take longer to draw than twenty five, and a six frame tap at frame thirty now lands before the program is reading a controller at all, which reads exactly like a button that has stopped working. |
||
|
Anachronaut
|
437ddf8ebe |
z zooms too, so a keyboard is not shut out of it
B was the only way to swap the view, and the game is meant to be flyable without a controller - the arrows fly it when there is no pad. Somebody without one had no way to zoom at all. Tested ABOVE the pad test rather than beside the arrows, and that is the distinction: which way the lander is flown is a question a controller answers better, so the arrows stand aside for one. How much of the moon is on the screen is not that kind of question, and a player with a pad may still have a keyboard in front of them. No edge to remember here either. The console delivers a key ONCE, which is the whole difference between a key and a held button. The check puts the z forty bytes into the keyboard file, because the console hands over one key a frame: a z two hundred bytes in is a z two hundred frames away, which is past the end of the capture and reads exactly like a key that does nothing. It cost a wrong answer first time. |
||
|
Anachronaut
|
a02d701efe |
Two zoom levels on a button, which the device already had
Forty columns and eighty are the same map, the same 8x8 cells and the same engine; only how many of them fit differs. The map is 128 by 128 either way and the moon is exactly 128 columns of it. And the front end scales whatever it is handed by the largest whole number that fits, so 320 by 200 at four times and 640 by 400 at twice fill the same glass. So the two modes ARE two zoom levels and nothing in the video device had to change to get them: forty columns shows under a third of the moon at twice the size, eighty shows nearly two thirds. Out for the orbit, in for the landing, and B says which. What did have to change is every screen coordinate in Lander, because the middle of the screen is 160 on one and 320 on the other. They now live in one block that setView copies over from whichever of two tables matches the mode, so a gauge reads a variable and never has to know which screen it is on. Several coordinates became sixteen bit on the way, since 620 will not go in a byte. follow already read HalfScreen and showLander already writes the world position straight through, so the lander itself needed nothing but its resting column. The moon is redrawn on a swap because it is filled as many rows deep as the mode shows, and a moon drawn 25 deep on a screen showing 50 floats over nothing. The swap is edge triggered. A pad is LEVEL and not an event, so a view that swapped while B was down would swap sixty times a second - which is not a zoom, it is a strobe, and it redraws the whole moon each time. The check for that holds the button for three hundred frames and requires the lander to land where a six frame tap left it; with the edge dropped it ends seventeen pixels adrift, which is the strobe costing it frames. Four checks, each seen to fail on its own break. The README's Lander entry also still described the relief orbit that the previous commit replaced, and now describes the one that is there. |
||
|
Anachronaut
|
85029d3b85 |
An altitude bar, and orbital speed marked on the drift bar
The orbit takes the lander off the top of the screen, and the panel only worked while the ground was in sight. Both other bars are rates: they say how fast, and neither says where. The altitude bar is height above the surface underneath, up the left edge, half a pixel of bar to a pixel of sky - the flyable band is about 256 pixels and the screen is 200 tall, so pixel for pixel would run off the top of the very screen it describes. Above the surface rather than above some fixed line, so it reads NOUGHT the moment the lander is down. The marks say where 64 sixteenths is. Without one that number is folklore: a pilot can feel that somewhere around here the falling stops and has no way to see where. The bar is a pixel a sixteenth from the middle at 160, so the marks sit at 224 and at the two pixels before 96, adjacent rather than overlapping - a bar at orbital speed would otherwise hide the thing it is being measured against. Both in magenta. Red and green are taken and they MEAN something here, how fast and whether it can be landed with, and an altitude is neither. White was the first choice and the ceiling check counts white to find its warning, so it read a warning that was never up - the suite caught that. Cyan was the second and it is the colour of a landing pad, which is checked as whole cells of it. groundLevel is factored out of restOnSurface, which had the same sum. Three checks, each seen to fail on its own break. Two flights, because no one flight holds both ends of the bar well: the climb reads 219 pixels and the descent lands and then stays landed. They fly on their own keyboard file - the shared one holds a key down every forty eight bytes for the held-thruster check, so borrowing it flew the lander from the keyboard and the controller at once and turned the gentle descent into a crash. |
||
|
Anachronaut
|
c514d5328e |
An orbit that comes back round, out of gravity minus the swing
The relief version could never make one. It only ever SUBTRACTED from gravity, so a lander a little too slow sank for ever and one a little too fast rose for ever - nothing in it could turn a fall around, because nothing in it ever pushed up. There was no periapse to have. Gravity minus the swing outwards has a sign change in it, and that is the whole mechanic. Below orbital speed the pull wins and the lander falls; above it the swing wins and the lander climbs; at 64 sixteenths they cancel and it circles. Falling buys sideways speed and climbing spends it, so a fall carries the lander past orbital and turns into a climb, and the climb pays it back and turns into a fall. The trade is the quarter square multiply, because the rate has to be the PRODUCT of the two speeds. Set by the vertical speed alone it drained a climb to nothing, and any minimum to stop that became a trap the climb spent its way into - measured freezing at 23 with a gate of 24 and at 3 with a gate of 4. With the product in it there is no gate: as the sideways speed goes to nothing the trade stops by itself. Half the product rather than a quarter or the high half. The high half alone is nought below a product of 256, which is a dead patch exactly where the turn begins, and a quarter still ran the lander into the roof before it came round - the whole sky is about 145 pixels. Measured, placed at 80 sideways and left alone: apoapse at -1024 with 59 sideways, periapse at -124 with 71, and round again at 165, 241, 299 and 369 ticks with no sign of decay. A period of about 22 seconds. The ceiling also spends one sideways when it wipes a climb. Without that it was a trap with no way out: the pin wipes the climb, so the trade sees neither fall nor climb and never touches the speed that is pushing the lander up. Measured pinned at the top with 117 sideways, unmoving, for the whole of a four minute flight. Tests/makedisks.sh needed the library path, since Lander now includes math.asm, and the app went from 2,924 bytes to 4,651 - mostly the 1,022 byte table - which is what the listing expectations move for. |
||
 AnachronautandClaude Opus 5
|
f5642f52b5 |
A ceiling that pins rather than ends
Climbing made a sixteen bit height count down past nought and round to 65535, so a lander that kept going came back through the bottom and hit the ground FROM ABOVE. Two thousand pixels of climb, which a full tank reaches easily. Pinned instead, and told so in the window. Leaving upward is RECOVERABLE - gravity is always there and a lander with fuel can always come back - so ending the run would punish a state the player can fly out of. What kills you out here is running dry a long way from the ground, which is a death somebody flew into rather than one a boundary handed them. TWO DIFFERENT LINES, and both were got wrong before they were got right. The warning covers being AT the ceiling or above it: compared against the ceiling itself, a pinned lander read as back inside the world the next frame and the warning was written and wiped sixty times a second, so it never appeared at all. The pin covers being STRICTLY above it: including the ceiling dragged the height back every frame and the lander could never descend, which is a lid nobody can leave and worse than the wrap. And only the climb is spent, never the fall. Zeroing the speed outright pinned it there for ever - gravity adds once a tick and a clamp running every frame wiped the pull nine times out of ten. The orbit check is gone, and the reason is in video.sh. Every window where the difference showed turned out to be a few frames wide: hold the thruster and both landers are pinned with their climbs spent, ease off and both land and freeze. A version of it passed against one disk and failed against another, which is a check measuring the boot time rather than the physics. Orbit is verified by measurement and said to be so, rather than left looking tested. cosmosLanderDry wants seventy million cycles now instead of forty: it spends the whole tank at the ceiling before it falls the length of the world. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
d896c9d433 |
Multiplying, on a machine with no multiplier
a * b = qs[a + b] - qs[|a - b|] where qs[n] is n squared over four because (a+b)^2/4 minus (a-b)^2/4 is exactly a*b, and the halves the flooring throws away cancel between the two terms. A multiply is two lookups and a subtract. AND THE TABLE IS BUILT BY ADDING, which is the part that makes it fit a machine with no multiplier at all. A table of squares would need squaring to fill; this one does not, because qs[n] = qs[n-1] + n/2, and n/2 goes 0, 1, 1, 2, 2, 3 - a number that steps up on every even n. So the whole thing is a running total and a toggle, and nothing harder than an add appears anywhere in building the thing that does the multiplying. 511 entries of two bytes, because a byte plus a byte reaches 510. That is 1,022 bytes of Data Memory, and it is the price: a kilobyte traded for an operation the hardware has not got. The operands go in memory rather than in registers. B cannot be stored and a product does not fit in one byte anyway, so two in and two out would spend more instructions shuffling than the multiply costs. Checked against nought, the commutation both ways round, a square, and 255 times 255 - which is 0xFE01 and the largest product two bytes hold. The square is the case the identity leans on hardest: the difference term is nought and the whole answer comes out of one entry. Wanted for Lunar Porter's orbit, where the trade between height and speed has to be proportional to vx times vy and could not be. Useful well beyond it: this is the routine every fixed point sum on this machine has been doing without. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
a069ee7a00 |
Orbit, and two bars that answer instead of reporting
Going sideways lifts the moon off you. Not because gravity weakened - because at speed the surface falls away underneath as fast as the lander falls towards it, which is what an orbit is. A GRADIENT OUT OF INTEGER ARITHMETIC. Gravity is one sixteenth of a pixel a tick and there is nothing between that and nothing, so it cannot be scaled down. Instead four times the sideways speed goes into a byte every tick and the tick's gravity is skipped whenever that byte carries: the fraction cancelled is the speed over 64, smoothly, with no multiply and no divide. At four pixels a frame it carries every time. That is the linear approximation; the honest one is the square, and wants a table. It did nothing at all for its first two versions. Once because the relief was a 256th a tick, so orbit wanted a speed no lander would reach; and once because A IS THE HIGH HALF of the shift register, so multiplying by four left the answer in A while the code read B, which is nought. The same trap as the scroll register and the pixel conversion before it. And a bar for the vertical speed beside the one for drift, both GREEN WHILE A LANDING WOULD SURVIVE AND RED WHILE IT WOULD NOT. That turns two numbers into one question - can I put down - and answers it at a glance. WHAT THIS COST: the flown delivery check. A recording is a list of buttons and not a flight, so replaying it under different gravity flies somewhere else; the delivery became a crash two columns short. The fixture is still there and is still a faithful record of what somebody did, and is no longer a record of what happens. That is the standing cost of a flown fixture, and it is worse than the transcript tests dropped earlier: those broke when an output moved, and this breaks whenever a NUMBER moves. Making the delivery reachable without flying - a way to start already carrying, or at a chosen base - is what would fix it properly. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
4b1c3d8e3f |
A missing file is an error, not a core dump
Naming a pad file that is not there printed the error and then said the machine had STARTED. MACHINE_OK is nought and the code returned nought, so the front end ran a machine whose clock had never been set up and divided by it: a typo in a path came out as a floating point exception and a core dump. The trap is two functions in one file with opposite conventions - machineStart returns MACHINE_OK for worked, machineRestart thirty lines up returns 1 for worked - and this copied the nearer one. Both of the returns I added last week had it. Checked now for all three files the replay suite is about, because the same mistake fits all of them, and re-broken to be sure: the check comes back exit 136, which is a signal 8, which is the crash. Found by somebody typing a path that was not there, which is the fourth thing this week that no test would have reached. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
60e0196fe2 |
A delivery, flown by hand and kept
Cyan base to red base: twenty five seconds of steering, recorded with --record-pad and replayed as a test. THE FIRST FIXTURE HERE THAT WAS PLAYED RATHER THAN WRITTEN. It is the only check that a cargo ever reaches anywhere. Several attempts at authoring a flight like it by hand got within two columns and no closer, which is a piloting exercise rather than a test - and the whole reason the recorder exists. What is checked is the FIRST LETTER of what the base answers. Delivered, Loaded, Nowhere and Not are 30, 22, 37 and 37 pixels of white in that cell, so a D is a delivery and nothing else is. Counting the whole message would pass on any message of the same length, and comparing the picture would fail the next time anything about a font changed. It took three flights to get here and two of them were lost to bugs in the recorder: one that recorded the wrong pad, and one that recorded a pad sampled on a different clock from the one the machine read. Both were found by somebody watching a replay and saying it was not what they flew, which nothing in this suite could have said. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
de1857f5f7 |
Record every pad, not the one that happened to be first
The first recording ever made with this came back 1,766 frames of nothing. It recorded pad NOUGHT and the controller was somewhere else - which pad one lands on is an accident of the host, the same accident that made Lunar Porter read all four in the first place - and a flight flown for the purpose was lost to it. So every pad is or-ed into the byte. A demo is a record of what somebody DID, and on a machine one person is playing the number it arrived on is not part of that. It plays back on pad nought, where --pad puts the first file given, and any program that reads more than one pad reads them or-ed anyway for exactly the same reason. --record-pad takes one file now rather than filling pads in turn, because there is nothing left for the second one to mean. The check for it plays a recording on pad ONE with nought holding nothing and requires the bytes back. That is the case that was missing: the round trip was tested and passed, on pad nought, which is the only pad it could not have gone wrong on. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
a163c670d0 |
A demo recorder: --record-pad writes what --pad reads
One byte a frame, in exactly the format the player takes, so a recording needs no conversion and there is no second format to keep in step. That symmetry is the feature, and it makes the strongest form of the claim testable: a recording is made OF a playback, and the bytes coming out have to be the bytes that went in. It exists because some inputs cannot sensibly be written by hand. Flying a lander from one base to another is a few hundred frames of steering that has to arrive somewhere eight cells wide, and several attempts at authoring one got within two columns and no closer. That is a piloting exercise rather than a test. Playing it once and keeping what happened is the answer. A BYTE FOR EVERY FRAME, written inside the loop that advances the recordings rather than after it, so a machine that jumped several frames at once still writes one for each. A recording is a timeline: one that skipped the frames nobody looked at would play back faster than it was flown. What is recorded is what the DEVICE WOULD REPORT, not the live state - a recording of a playback that wrote the live state would be a file of noughts. And it is flushed as it goes, because a recording is usually stopped by whoever is playing rather than by the program ending, and a demo lost to a buffer is a demo flown twice. Tests/replay.sh is where this and whatever follows it are checked. Twelve scripts now. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
caf5e1f99d |
A base speaks in the window, not into the world
Two bugs with one cause. The console draws into the map, so a message printed while flying was a message the lander then flew over - and printing scrolls, so every one of them moved the whole world up a row. The window is at a screen position and forty cells wide, and neither is true of it. So the window is two rows now: the gauge, and whatever there is to say. The letters are ordinary tiles, because the character generator starts at the space and glyph n is character n less thirty two. The rest of the row is blanked after every message, or a short one would leave the tail of a long one behind it. Opening the throttle wipes the line, because a message that outlived the moment would be read as describing this one. The crash still goes to the console, deliberately: it is the last thing the program says and it should survive the program. A or Start continues from a message as readily as a key does. Somebody flying on a controller should not have to reach for the keyboard to say they have read something. AND TWO TESTS WENT WITH IT, which is the interesting part. cosmosLanderSoft and cosmosLanderPadOne asserted on lines in a transcript, and the lines moved off the console - so both went on passing while checking nothing at all. A test that asserts a side effect rather than the thing itself is always one refactor from being decorative. What they were for is now checked in the picture, where the message actually is. The lander check moved earlier too. The window grew to two rows, so by 1.5 million cycles the lander had climbed behind the status bar - the window doing exactly what it should, and leaving the check counting six pixels of a forty pixel lander. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
bfb515e23b |
Cargo: bases with names, and a landing that is not an ending
Four bases, told apart by the scheme their pad is drawn in, so "the cyan one" is a thing a person can say and a thing the machine already knows. Yellow is missing on purpose: it is the lander, and a base the same colour as the thing landing on it would be a poor joke. Land empty at a base and it loads cargo for the base ACROSS THE MOON, two along - so the pairs are cyan with red and green with blue, and the wrapping surface is a route rather than scenery. Land carrying at the right one and it takes the cargo and pays eighty units of fuel. Land at the wrong one and nothing happens, which is why the destination will want to be on the screen. A LANDING NO LONGER ENDS THE RUN. The lander rests where it is, exactly on the surface with both speeds zeroed, until the throttle opens again - which is the only way to stop being landed. Gravity does not pull on something already sitting down, and a base does not hand out cargo sixty times a second to a lander parked on it. The pad array holds the base's number plus one rather than a flag. Nought still means no pad, so it is still one lookup, and a flag would have to be followed by "and which of the four" - the same walk done twice for an answer already in hand. Pads are eight columns rather than four. Four was 32 pixels in a moon 1024 round, which is a target somebody flying by feel misses over and over. WHAT IS NOT COVERED, and why: the delivery and wrong-base paths need a lander flown from one base to another, and hand-authoring a recorded pad input that hits an eight column pad across a 128 column moon is a piloting exercise rather than a correctness one. Several attempts got within two columns. Loading, crashing, landing off a pad and running dry are all covered; delivery is built and flown by hand. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
7257ad369c |
Landing pads, carved rather than looked for
A random walk does not leave flat ground and a lander wants some. Four pads are cut into the moon after it is generated, each four columns levelled to whatever height its first column happened to have - so they sit in the landscape rather than on a shelf above it. The moon decides where they are; this only decides that they are flat. Searching for flat spots was the alternative and it can fail, which means a fallback that carves anyway - the carving, plus a search nobody needed. They are marked by an ATTRIBUTE and not a tile of their own, which costs no art at all: a nibble is added to every index in a tile, so one solid block is grey moon or a cyan pad depending on the byte beside it. Which columns are pads is an array, because asking has to be one lookup. Four comparisons per column per row is 12,800 of them for one screen, and the landing verdict asks the same question again. THE LANDER STARTS ABOVE ONE, because that is where a porter's day begins. Starting in the middle of nowhere meant a straight descent landed in the middle of nowhere, which is a fine thing to be able to do and a poor thing to have to. That change cost the crash test its teeth, and the way it did is worth keeping. It held nothing at all and let the lander fall - and a short drop onto the high ground of the base you started above is survivable, which is correct, and left the test saying nothing. It holds Right now: lateral speed has no limit and nothing slows it, so a slide always ends badly however the rest is tuned. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
6073086584 |
The system takes a leftover window down
Lunar Porter put a fuel gauge up and never took it away, so the shell came back with FUEL across the top and the cursor underneath. Clearing did not help: a window is a layer at a SCREEN position that does not scroll, which is exactly what makes one left behind unpleasant - it sits over whatever comes next and cannot be scrolled off, cleared away or typed past. Taken away rather than given back, like the sprite table and for the same reason: nothing the shell draws is a window, so there is nothing to restore. And a program that FAULTED while one was up could not have taken it down itself, which is why this belongs to the system rather than to whichever programs remember. The check for it needed writing twice, and the first version was the familiar kind of wrong. It counted the gauge BAR's colour - and the bar disappears on its own whatever happens, because it is drawn with a tile the screen save puts back, so the check passed with the teardown deleted. What actually survives is the LABEL, in font tiles the shell needs anyway. So the screen is cleared afterwards and read cell by cell. With the window down a cleared row is "> " and a cursor; with it up the same row is F, U, E, L. Cells one and three being empty is the whole difference, and it is 29 and 22 pixels of it rather than a threshold somebody has to believe. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
2274be4b68 |
Lunar Porter, rung three and a half: fuel
Every thruster costs a unit every tick it fires, so holding two at once costs two - the honest price, and it makes a drift you corrected expensive in a way a drift you avoided is not. AN EMPTY TANK IS NOT AN ENDING. There is no message and nothing stops: a lander with no fuel is still flying, it just cannot do anything about where. What happens next is gravity, and gravity is patient. The test for it holds the thruster from the first frame to the last and crashes anyway, which is what says the fuel is real - a lander that could hold Up for ever would land every time, and the economy this is the first half of would have nothing to buy. The gauge is in the window, which is what the window was built for two commits ago: a bar at a SCREEN position, so the moon turning underneath does not carry it off. Thirty five cells after a label, redrawn whole every frame because seventy bytes out of one port is cheaper than working out which of them changed. A byte of fuel, and a byte is enough. Over eight it is a bar of up to thirty one cells - a shift, because there is no divide - and at a unit a thruster a tick it is about forty seconds of holding the engine open. Sixteen bits would be more arithmetic for a number nobody reads to the unit. Cargo and the bases are the other half. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
17c8da111f |
A window: a layer that does not scroll
The map moves and this does not, which the map alone cannot express. The scroll registers move ALL of it, so a score printed into the map slides away, and one printed into whichever rows the view happens to be showing jumps a pixel at a time as the fine offset changes. Port 0x3D is how many rows tall and 0x3E is which row it starts at. Nought tall is no window, so a cleared screen has none and every program written before this means what it meant. A start row is a register because a status bar along the bottom is as common as one along the top. IT HAS ITS OWN MEMORY, and that is the argument for it. The cheaper design draws the top rows of the MAP without the scroll applied - no new memory, one register - and makes those rows part of the playfield's ring, so a game that scrolls vertically has to route its world around its own scoreboard for ever. The point of a status bar is that it is not somewhere in the level. Lunar Porter does not scroll vertically today and will the moment an orbit is a thing you can reach. 0xC000 in the screen bank, which the map does not reach: it ends at 0xBFFF. Same cells, same tiles, same pages, same schemes. Being in the screen bank makes it per screen, so flipping the buffer flips the status bar with it - what a double buffered game wants, and surprising the other way round. Drawn over everything, sprites included. A sprite that could cover the fuel gauge would be a bug in every game that had both. Tile modes only. In bitmap mode the picture is using that memory, so a bitmap program pins things to the screen with sprites, which are in screen coordinates for the same reason. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
e3eccd17a8 |
Settle the view before saying how the landing went
The console draws into the map and the map is what is being scrolled, so a message printed while the view was three pixels into a cell came out three pixels off the top, with as much of its first row missing as the cell above it had lost. The flying is over by then, so the fractional part of the view has no more work to do. Putting it back is what makes the whole message visible. This is not the general problem. A status bar that has to stay readable WHILE the map moves is a different thing entirely, and nothing here solves it. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
a074a831f0 |
The shell scrolls, and the moon was drawn where nobody was looking
Lunar Porter never put the row origin back. The map is a ring 128 rows tall that the screen shows 25 of, and the shell leaves that origin wherever its last command finished - so a moon drawn into rows nought to 24 while the screen is reading from row forty is a moon nobody can see. It came out as terrain missing, or half there, depending on how far down the prompt had got. Running Pad first was enough; so was holding Return. Nothing here is tidiness. It is the difference between the rows a program WRITES and the rows the screen READS, and only one of those is under the program's control. Grid has always known this; Lander did not. The check for it needed writing twice. Forty returns caught nothing, because the shell runs an eighty column screen which is FIFTY rows tall - forty returns fill it and never scroll it, so the origin was still nought and the test passed against a build with the fix taken out. The screenful that matters is the one the shell is using, not the one the program is about to ask for. At eighty it is 28,608 pixels of moon with the fix and none at all without it. break.sh is what said so. The first version of this check looked exactly like a passing test. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
f7be843ed9 |
Lunar Porter takes any controller, not the first one
A controller does not always arrive on pad nought. The front end hands out the numbers the host gave it, so a game that reads only the first one works on the machine it was written on and silently does nothing on the next - which is the shape of "the pad is detected, Pad shows it, and the game ignores it". Four reads and three ORs. One person flies this and which socket they plugged into is not a thing they should have to know. Presence is any of the four bits rather than the low one, for the same reason. The manifest's pad column takes several fixtures now, comma separated, and they fill the pads in turn. So cosmosLanderPadOne holds nothing on pad nought and flies the whole landing on pad one - a test that fails on the version of this program that shipped an hour ago. Also confirmed while looking: raylib 6 does refresh which gamepads are ready every frame in PollInputEvents, so a hot-plugged pad should be seen. Whatever is stopping that is above us and worth a separate look. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
df50c2f0f8 |
The pad was working; the game was told there was not one
0x64 counted only the RECORDED pads. So a controller plugged into Voyager reported its buttons perfectly, and every game asking whether there was a controller was told no - which is exactly what Lunar Porter asked, once, at startup, before falling back to the console for the rest of the run. The cause is worth naming: a front end calls padSet every frame for every pad, so "held nothing" is the commonest thing it says and cannot also mean "there is no pad here". Connected is said separately now. Pad nought is always there behind a window, because the keyboard is behind it - which is the useful answer rather than the literal one. And Pad.asm, which is what should have existed before any of that guessing began. It prints a line whenever a pad changes, and tells apart the three states that look identical from inside a game that will not respond: one nobody noticed, one mapped to nothing, and a mapping that is wrong. WHY A PROGRAM AND NOT A PRINT IN THE FRONT END: because the question is what the MACHINE can see. A front end reporting what it thinks it is sending answers a different question, and the gap between those two is the whole of this bug. It also found that osPrintNumber takes A as the HIGH half - the same way round as the shift register and every other pair here, and not what a byte in A wants. Every value came out 256 times too big. Gravity is one frame in ten rather than six. The ratio between thrust and gravity is the feel; how often the tick comes round is how fast that feel arrives, and one in six was still touchy. Same lander, more time to think. And the verdict waits for a key. It printed and left immediately, taking the screen with it - so the one thing worth seeing, the lander sitting on the ground it had just reached, was gone before it could be looked at. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
8eb4e4d67e |
Lunar Porter, rung two: it lands, or it does not
The terrain is an array in Data Memory rather than something read back out of the map, and that is the whole reason this is cheap: the ground under the lander is one index into 128 bytes, where asking the screen would be a transfer through the controller every frame. The column is the world position over eight, masked to the moon's 128. The surface is that column's row times eight - three turns left of the shift register, since a row is at most 24 and 192 fits in the low half. The feet are the lander's top plus its eight pixels. WHAT DECIDES IS THE SPEED AT THE MOMENT IT ARRIVES. Both of them, and both have to be gentle: three quarters of a pixel a frame downwards and half of one sideways. Sideways is the tighter on purpose, because a landing that was soft downwards and sliding is a lander on its side - which is the interesting half of the difficulty, and the half the drift bar was blind about until it existed. Two fixtures say it works, and they differ only in what was held: one holds nothing and falls the whole way, the other pulses the thruster six frames in sixteen and survives. Same terrain, same seed, same keys. Also: the gamepad did nothing, and the reason is that the four direction buttons are the D-PAD. A lot of controllers made this century have one nobody uses - the thumb goes on the stick, which reports as an axis rather than a button - so a pad that was plugged in and working correctly did nothing at all. The stick counts as held past halfway now. Untested here, because there is no controller in this environment and the suite runs headless; Voyager also says at startup which controllers it can see, so a pad that still does nothing can be told apart from one nothing noticed. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
db0c26e13f |
A bar for the drift, and a lighter touch sideways
A moon has no air, so a sideways drift never stops by itself and stopping one means cancelling the velocity EXACTLY. That is not hard to do; it is hard to do blind, which is what it was - a number nothing on the screen said anything about. So sprite one is a bar whose width is the drift. It runs right from the middle of the screen for a rightward one and left for a leftward one, so which way is as plain as how fast, and stopped is the one state with nothing drawn at all. The whole of it is a target width written once a frame; the device stretches one tile into it and the program draws nothing. Sideways thrust is one a tick rather than two. At two, the smallest correction available was twice the size it needed to be and overshooting was the normal outcome. WHICH ZERO MEANS NOTHING TURNED OUT TO MATTER. A target width of nought is the NATURAL width, not an empty sprite - so a bar with no drift in it came out eight pixels wide, sitting at the middle of the screen, saying "stopped" in the same shape it says "drifting slightly". What draws nothing is a SIZE of nought, which is the other zero in the other byte. Both meanings are deliberate and documented and it still caught me out inside a week of writing them down. The check for it earned its place by failing on that before it was found, which is the best evidence a check can offer. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
b1dde7908c |
Lunar Porter flies on a controller
A held thruster burns every tick it is held for, which is the whole reason the pad exists: the console can only say a key went down, so a thruster driven by it could be pumped and never leaned on. The burn happens on the same tick gravity does, and for the same reason - a sixteenth of a pixel is the smallest step this arithmetic takes, and applied sixty times a second it is an enormous acceleration. On the tick, thrust and gravity are two numbers whose RATIO is the whole feel of the thing. Position still moves every frame; only the acceleration is stepped, and nothing can see that. Two against gravity's one, so climbing and falling are the same speed. Three was the first try and it left the moon after about a second of holding. If there is a pad the console's arrows are ignored, because under a window the same keypress reaches both - the pad as a level, the console as a byte - and a thruster that fired twice for one press would be a mystery to anybody tuning it. q still quits, since a pad has no letter for it. With no pad the arrows still burn once a press, which is the most that can be done down a wire. And break.sh now rebuilds the disk images as well as the binaries. Half the things worth breaking here are SplitBit assembly rather than C, and those live on the fixture disks - so an edit to a .asm file changed nothing the suite could see, and the tool reported that nothing caught the break. That is the exact lie it was written to prevent, turning up in a new place. With the disks rebuilt it catches this one: the lander falls between the two captures instead of climbing. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
fed1453e6e |
Controllers: four pads that say what is held
The console says WHICH KEY WENT DOWN, which is the right shape for typing and the wrong one for playing. A game wants to know what is being held, this frame, possibly several things at once, and a stream of presses cannot say that: a key that is down and staying down sends nothing at all. Lunar Porter's thrust is a burn per press for exactly that reason. So a pad is its own device on ports 0x60 to 0x6F, reporting a LEVEL. One read gives every button at once, holding is the natural thing to express, two directions together cost nothing, and reading does not consume it - a game may ask twice in a frame and be told the same thing both times. Four of them, because a party is four. They cost a port each and nothing at all when unused. The directions are the low nibble so "which way" is an AND with 0x0F; the buttons are the high nibble for the same reason. 0x64 says which are really there, so a game can ask for a controller rather than sitting silent while somebody presses things at it. They never interrupt: a game polls once a frame because that is when it draws. KEY-UP ON THE CONSOLE WAS THE OTHER WAY TO DO THIS AND WAS REJECTED. A terminal hands over characters and can never report a key coming up however it is asked, so it would have been a thing that worked behind a window and silently did not down a wire. A separate device can honestly say it is not there. Voyager drives pad nought from the keyboard as well as from any real controller, OR-ed rather than chosen between, so a game written for a pad is playable on a machine with none and unplugging one mid-game does not leave somebody holding nothing. And a recorded path, which is what makes any of it testable: --pad names a file of one byte a frame, and the manifest has an eighth column for it. A BYTE A FRAME AND NOT A BYTE A READ - a level asked twice in one frame has to answer the same both times, and a file that advanced per read would depend on how the program happened to be written. Voyager's own tests run headless with nobody holding anything, so without this the device would be exercised only by somebody playing: the state the console's line editing was in when it broke twice in two days. 0x50 is the timer, not free. The block this went in was chosen after looking rather than before. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
88ecb208f4 |
The coarse scroll register was being sent the wrong register
CALL eighth OUTA 0x36 RET puts A back the way it found it, so the column origin was written the high byte of the position that had been passed in, and the answer the subroutine had worked out went nowhere. The fine register was computed inline with OUTQ and was correct, which is exactly what it looked like from the outside: smooth scrolling within a cell that never advanced one. Q is the only register that crosses a RET. Every other answer in this program already came back in it; this one had been written as if A would do, and A very nearly does, which is what makes it worth a comment rather than a fix. Gravity was Jupiter's. A sixteenth of a pixel per frame per frame is the smallest step this arithmetic can take and it crossed the screen in a second, so it is applied one frame in six instead - which divides the pull by six and costs a byte and a compare. The alternative was a finer unit for velocity than for position, and that means a shift every time one is added to the other, twice a frame, for ever. And the check that catches all this now looks 1.5 million cycles in rather than twelve. The first number came from assuming a program that saves a whole screen takes a long time to start; it does not, and by twelve million the lander had flown seven hundred frames and left the picture. A capture near the beginning is worth more than a tuned one - there is less between it and the start that can move. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
d6c81fa32c |
Lunar Porter, rung one: it flies
A lander over a moon that wraps. Landing, crashing, fuel, cargo and bases are not here - this rung exists to answer whether it FEELS right, because everything after it is bookkeeping and none of it is worth building on a lander that is no fun to fly. The moon comes for free. The map's column origin is a ring in hardware, so 128 cells is 1024 pixels of surface with no edge and no seam to cross. Position and velocity are sixteen bit in SIXTEENTHS OF A PIXEL, and the unit is the design: gravity is a small number added to a velocity and a velocity is a number added to a position, with no multiply or divide anywhere. 1024 pixels is 16,384 sixteenths, which is 2^14 - so going all the way round is an AND with 0x3FFF rather than a comparison, and it is never wrong at the seam. The lander never moves sideways. The world scrolls under it and it sits at the middle of the screen, which is a byte a frame instead of two and is also what makes the wrap invisible: there is no moment where it jumps. One key is one burn. The console says which key went down and there is no such thing as a key coming up, so a thruster cannot be held - a press adds to the velocity once. That is a property of the machine rather than a choice this program made, and it reads as pumping the engine. Four bugs found by running it, all worth keeping written down: B CANNOT BE A LOOP COUNTER here. Every comparison is an INIB, so the count was overwritten by whichever bound was last tested and the loop reset itself for ever. Counters that outlive arithmetic live in memory. A subroutine answers in Q, and the AND after it read A. The moon came out flat because it was testing the height against 1 instead of the random number. Row minus height, not height minus row: they are equal at the surface, equal does not borrow, and the surface row has to be ground. And the shift register has A as its HIGH half. Written the other way, the view scrolled by 256 cells for every one it should have. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
5222c85100 |
More fills the screen it is on, not the screen it was written for
Twenty two lines was right when there was one screen size. It still is on the forty column screen and wastes three fifths of the eighty column one, so More asks the rows register instead - which is readable for exactly this sort of reason. Rows minus three is twenty two on a twenty five row screen, so nothing changed underneath anyone already reading files this way. It fills a bigger screen and leaves a smaller one alone. A bitmap screen has no rows and says so with a nought, which through an eight bit subtraction would be 253 lines. Anything under five falls back. The existing test stopped testing paging the moment this worked: 32 lines fits in a 47 line page, so the file never paged and the recording lost the prompt entirely. The fixture is 60 lines now - the INPUT needed moving, not just the output, which is the failure this project keeps meeting. And cosmosMoreNarrow, which runs Mode first and pages the same file on the forty column screen. Two recordings of one file at 47 lines and at 22: a More that went back to a constant would make them the same length. Both were verified with break.sh, and the first attempt was a bad break rather than a bad test - it replaced one of two reads of the rows port and the other still fetched the real value. Which is a fair argument against reading a port twice, so it is read once and kept now. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
fba1b553d2 |
Depth: a ball behind the near pillars and in front of the far ones
The demo for what V5 added. Four pillars at four distances, each ONE 8 by 8 tile stretched to its own width and height, and a ball walking past all of them at a distance between two. What it shows is the thing an ordering cannot. The ball is sprite NOUGHT and every pillar is numbered after it, so table order puts the ball in front of all four - and it is still hidden behind two of them, because the depth buffer is asked per column. Caught mid-straddle in the checks: the ball is 48 wide and the pillar 32, so it shows on both sides and nowhere across the middle. Writing it found the conceptual trap in the feature, which is now written down where somebody will hit it. The pillars first carried their own distance in their entries AND wrote that same distance into their columns, so each was asked whether it was in front of itself - and 20 is not nearer than 20, so all four vanished. THE BUFFER IS WHAT HAS BEEN DRAWN AND A SPRITE'S DEPTH IS A QUESTION ASKED OF IT. Scenery writes it; it does not ask. Also found that a scheme only gives a colour to index one. The default palette sets each scheme's paper and ink and nothing between them, so art drawn in index two comes out black until a program writes a palette. And the fixture disk's root directory was full: four blocks, 32 entries, all taken, so adding an app failed the whole disk build. Loudly, which is the right way round - but it is a wall that moves for free, so it is eight blocks and 64 entries now. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
cb898450b5 |
Sprites that scale, and a depth buffer to hide them behind
A target size in PIXELS rather than a multiplier, which is the whole of why this is usable here. A billboard at distance d wants to be k/d pixels tall, and that is a number a program has anyway - out of a lookup table, most likely. A multiplier would have to be a fixed point fraction arrived at by dividing, and this CPU cannot divide. Zero on an axis means the natural size, so every sprite written before scaling existed still means what it meant. The two axes are independent, and that shape - one tile wide at its own size, stretched to whatever height a distance says - is a wall column in a pseudo-3D game. Measured: a DDA step costs 85 cycles, so 80 columns of ray casting is about 85,000 cycles, or 12fps. Drawing those walls from the CPU instead would be 256,000 writes, fifteen frames of cycles for one frame of screen. The device doing the pixels is what makes such a game possible at all here, not merely faster. And a depth buffer, one byte a screen column at 0xD000, written by the program. A sprite with a depth draws only in the columns it is in front of. PER COLUMN, and that is the point: a billboard is nearer than the wall at one end of itself and further at the other, and no ordering of the table can say that. Table order settles sprites against each other; the buffer settles them against the scenery. Zero means no test at both ends, so a program that never writes it behaves as it did before it existed. The entry grew from 8 bytes to 16 - now, while two programs use the table, rather than once a game is written on it. Bytes 0 to 7 kept their meanings, so Sprite.asm needed no change. The pass is rewritten to walk where a sprite is GOING rather than where it came from, which is what makes a stretch and a squash one operation. It also made flipping fall out: turning the source coordinate round mirrors the tile order and the pixels inside each tile in one step, where drawing tile by tile had to be told to do both. All 111 checks passed unchanged at natural size, which is what says the rewrite changed nothing it should not. Clipping moved out of the inner loop and had to: a target size is sixteen bits, so a sprite asked to be 60,000 pixels tall would have been sixty thousand turns of a loop that drew eight rows. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
f8c3db5d56 |
A tool for breaking things, since doing it by hand went wrong twice
A check that passes proves nothing until it has been seen to fail. Doing that by hand failed twice in two days, and BOTH TIMES IT LOOKED LIKE A RESULT - the suite ran, went green, and read exactly like "this check does not catch that". Once the edit produced code that would not compile, make failed, the exit status was not looked at, and the previous binary ran the suite. Once the anchor was right and the filename was wrong, so nothing was edited at all. Neither had anything to do with header dependencies, which have always worked: DEPFLAGS is -MMD -MP and every .d is included. What was missing was a harness that refuses to report a result it did not earn. So Tests/break.sh checks every step of its own work and treats anything unexpected as a hard error rather than a green run. Not finding the break is the answer it exists to give, and it is worthless if it can also be the answer when the break never happened. It restores the file on the way out, including on an interrupt. It is not in the suite and docs.sh does not count it, for the reason makedisks.sh is not counted turned round - but being left out of the count is not being left out of the manual, and that gap is where a script goes undocumented for months. So docs.sh now requires both of them to be described, and caught this one being missing. Also: video.sh reads the fixture disks and does not build them, so after make sanitize clears the build directory it reported SEVEN product-looking failures for a missing file. It builds them now and says so. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
9eed23120f |
Four pages of tiles, in bits that were already there
A tile number is a byte and a byte reaches 256, which is not many once a font has taken 135 of them and a game wants a character, a background and a wall. Bits 4 and 5 of the attribute now say which page of 256 the number is in - bits already written on every cell and every sprite, and reserved for this since the attribute was defined. Four pages of 16K is 64K, which is the whole atlas, so THE FOURTH PAGE IS THE MEMORY THE SPRITE TABLE AND THE PALETTE ARE IN. That is not a hole in the design; it is the answer shared video memory has always given, and it is checked rather than forbidden. The atlas is 1024 tiles, and what a program spends on sprites and colours comes out of them: no sprites means page 3 is art, and sprites means 768 tiles and a reason. The page is a property of the CELL and not a mode, so one screen shows tiles from all four at once and nothing has to decide which page it is in. Both places a tile is drawn from now ask one function where the art is. They would otherwise drift: the sprite pass was written days after the map pass and neither is where the other is looked at. Nothing in CosmOS changes. The shell draws from page 0, which the screen save covers; a tile left in another page is invisible unless a map cell names that page, and the map is given back or cleared. Both breaks were tried and both failed the checks - and the second had to be tried twice, because the constant it needed lives in video.h and the harness was only editing video.c. That is the same silent no-op as yesterday's uncompiled break, in a different disguise. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
a916103a7f |
Sprites: things that move without the screen moving
Everything drawn on this machine was in a cell. Something between two cells meant rewriting both; something moving a pixel at a time meant rewriting them sixty times a second, which is affordable for one thing and not for twenty. A sprite is put at a pixel and the device draws it over whatever is behind, so moving it costs two bytes. MADE OF TILES, which is the decision the rest follows from: m by n taken in reading order from one index, so there is no second pixel format, no second kind of memory, and nothing a sprite can show that the map cannot. A 16 by 16 character is four tiles and the background can name the same four. 256 entries of 8 bytes at 0xC000 in the atlas - eight so the entry address is a shift, the same no-multiply argument as the palette's four. Position is signed and sixteen bits, because 640 by 400 does not fit in a byte and a sprite has to be able to sit half off the left rather than appearing whole at the edge. A PIXEL OF ZERO IS NOT DRAWN, or every sprite is a rectangle. Tested before the attribute is added, so a hole belongs to the art and not to the colour scheme. The same rule the other way round is what "behind" means: drawn only where the background pixel was zero, so a thing walks behind a pillar and in front of the floor in one frame. All of them draw, every frame, so they cannot flicker. Real machines dropped them per scanline because they had a fixed number of shift registers; this has a loop. The limit is the size of the table, which is a constant rather than a property of what is on screen. And the system takes them down at exit. The sprite table sits in the gap the screen save walks around - to the end of the map, then the palette - and that is right, because nothing the shell draws is a sprite: there is nothing to give back, only something to take away. Otherwise a program that put a ball up and left would leave it over the prompt, in front of everything, with nothing able to type it away. Sprite.asm deliberately leaves its own, because a program that faulted could not have cleared it. Every check here was re-broken and failed: transparency, reading order, draw order, priority, and size. Size needed breaking twice - the first attempt did not compile, and a silent build failure had left the old binary passing. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
eee95ef0ce |
Flip says the true thing, and the checks that let it lie
Two bugs, both in what the demo claimed rather than in the device. The assembler has no string escapes, so the "\n" written in a literal printed as a backslash and an n. A newline is a byte; Say.asm has always written one as 0x0A 0x00 and this now writes it out of the console port. And the line whose whole job was to still be there afterwards was wiped out on the way back, because the program called osTakeScreen - which restores the screen AS IT WAS BEFORE, so the tidy-up erased the one thing the demo was pointing at. It did not need saving: nothing it touches is the shell's. A program that damages nothing should not ask, and asking anyway costs it the screen it was standing on. Which turned out to be untrue as written, and that is the third thing. Flip drew with a tile of its own, and the system copies the font back over every tile at exit - so the filled screen went blank the moment the program left, and the check that the system put the display back could not tell a restored screen from an abandoned one. It passed with the restore deleted. So did the check that a program can show the other screen at all: a blank screen counts as one colour just as well as a filled one does. Now it fills with 0x0A, which is an asterisk in one of the reversed colour schemes: paper is the colour and ink is black, so a whole screen is drawn with NO TILE REDEFINED and it survives leaving. Both checks ask for the commonest colour in the picture rather than counting colours or naming a pixel - the font's only blank glyph is the space, whose attribute nibble is nought, so a filled screen is always a pattern and which pixel lands on paper depends on the character. Both were re-broken afterwards and both failed this time. Also cosmosFlip, a transcript test, which is what would have caught the printed backslash in the first place. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
023362b05a |
A second screen, and one port to say which is shown
A screen drawn where it can be seen is seen half drawn. A program that moves forty things and rewrites the map underneath them is wrong for as long as it takes to put them all right, and at a megahertz that is long enough to look at. So the device brings a second screen bank, on port 0x3B, and port 0x3C says which of the two is displayed. Everything a program draws into the other one is invisible until one byte shows the whole of it at once. ONE REGISTER IS ENOUGH, where the hardware this imitates needed two. The other said which screen the CPU's window pointed at; there is no window here, because a program reaches a bank through the memory controller by its number. Writing to the screen that is not shown is a matter of naming its bank, and the device never has to be told. And a flip cannot tear: a frame is drawn from one bank in one go, so a flip either happened before that frame or happens before the next. There is nothing to race, where the real machines had to catch the few lines between frames to swap in. The console draws into whichever screen is displayed rather than one of its own, so a fault message lands where somebody can read it even if a game had flipped. And CosmOS puts the displayed screen back at exit, the way it already puts back the cursor and the ink: a program that faulted while flipped could not have, and a shell that only came out right for programs which remembered would come out wrong the day one crashed. Flip.asm is the worked example. It deliberately does NOT restore the display itself - that is the point of the paragraph above, and it is what makes the system's guarantee the thing under test rather than the program's good manners. Written the other way round first, where it passed with the guarantee deleted. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
66e7b84272 |
The screen is two banks: an atlas and a screen
Tiles and colours are written when a program loads; the map is written whenever anything moves. Sharing one 64K bank made them compete for room neither needed all of, and had a worse consequence than being cramped: a bitmap covers the whole bank, so entering bitmap mode destroyed the font. A program could not draw a picture and then say anything about it. Split, each gets a whole bank. The atlas holds the tiles and the palette, the screen holds the map or a bitmap, and a picture now costs the map and nothing else. It also leaves 48K free in the atlas, which is where the sprite table and a second page of tiles are going. No new mechanism was needed. A bank is registered by naming the port that owns it, so a device with two banks needs two ports that own memory: the base port keeps the atlas, since tiles have been at 0x0000 since there was a screen at all, and 0x3A owns the screen. The registry now answers honestly about which ports in the block bring memory, where it used to say all sixteen did. CosmOS never addresses video memory except in one place - the screen save, which walks 196 pages of it. The page number already says which bank a page is in, so screenBankFor works it out rather than keeping a second list beside screenPageFor. Grid and picture.asm register both banks; colours.asm only touches the palette and needed none of it. Tests/video.sh names the memory every write is for, because an address cannot: tile 5 and bitmap pixel 5 are both 0x0005, and a helper that guessed would be right for the tiles and silently wrong for a picture. And picture.asm gained a check, because this change broke it and nothing noticed - registering the second bank leaves DestBank pointing at it, so the palette went into the wrong one and the picture came out black. It was the only thing here found by looking rather than by a test. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
2abc8281df |
Loops, and the scripting language is a language
while and for. Both only mean anything in a script, because a loop goes back to the line that opened it and a prompt has no line to go back to - and both say so rather than doing something surprising. THE SCRIPT READER KEEPS THE POSITION OF EVERY LINE before reading it, which is what makes any of this possible: by the time a line has been read the reader is past it, and a line is not a fixed size to subtract. Three words per line, and the block is read again on the way back so the pointer into it means what it meant - the same thing nesting one script inside another already did, for a different reason. THE TWO LOOPS END DIFFERENTLY, and that is the design rather than an accident. A while is taken away at its end and its own line asks the question again, so nothing has to be remembered. A for is not: how many words it has used is kept in the block, and its line reads itself again and counts one more off the front. That is a byte in a block instead of a copy of the word list in every one of them. Blocks grew from a byte to a record of sixteen - state, kind, words used, and where the line that opened it was - and sixteen because A and B are a shift register, so four rotations turn a block number into its offset. The history and the variables are addressed the same way for the same reason. Nested loops, an if inside a loop, a loop inside a branch nobody takes, and a for with no words: the last two run no times rather than once, which is the case worth having a test for. Three things found by running it: textSame asks whether two WHOLE strings are the same, so "in red green blue" is not "in". The word has to be split off before it is compared. A for typed at a prompt complained about while, because both arrive at the same place. One message that names neither is better than one that names the wrong one. And docs.sh caught a naming convention nobody had written down: it recognises a packed name by its label ending in "Name", so ForName2 was silently not counted. It failed the right way round - saying the run was shorter than the count claims rather than passing - but the convention now lives where the names are and not only in the checker. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
16f8232a35 |
Lines that are only run sometimes
if, else, end, and same. IF TAKES A COMMAND, which is one rule rather than two and is why comparing values needs no syntax of its own: "same" is an ordinary command that fails when its two words differ, so "if same $a $b" falls out of the rule instead of being an exception to it. Anything else that can fail is a question too - "if load Snake.sbx" is a perfectly good one. The shell already had the other half. LineFailed exists because a script stops at the first line that did not work, so every command was already saying whether it had, for a different reason entirely. A BLOCK HAS TWO KINDS OF NOT-RUNNING. One where an else would turn it on, and one where it would not - which is what an if pushes when something above it is already being skipped. That is what makes nesting need no looking down the stack: the top of it says everything. A branch nobody is taking is not even looked at. The skipping happens BEFORE the names are filled in, so a variable mentioned in a branch that is not running is not an error - a line nobody runs must not be able to fail. AND LINES MAY BE INDENTED, which they could not be before there was anything to indent inside. Nobody writes an if inside an if without indenting what is in them, and a leading space used to make the first word empty and match nothing. Found by writing the test script the way anybody would write one. CALL commandFailed became BRI commandFailed in nine places. It never returns - it marks the line and branches to the prompt - so calling it was a lie that cost a Stack frame each time, and fourteen other sites already branched. THE LINT RULE FOUND THIS, three days after I wrote the rule and on my own code: two false positives that were really the linter being right about a CALL that is not one. It does not fix the leak on its own, since a failure inside any called routine still abandons that frame, but it removes the cause of the commonest case and makes the code true. The mechanical edit then left a BRI prompt stranded behind one of them, and the linter caught that too. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
4b109f704c |
The shell starts each line with the Stack where it left it
Every failure in this shell abandons a frame. commandFailed is reached with CALL and never returns: it marks the line and branches to the prompt, which is the idiom every command uses and is why a failure needs no unwinding anywhere. What it costs is the frame of that call and of everything between the prompt and it - twenty bytes for a name that was never set, more from somewhere deeper - and nothing ever gave them back. MEASURED BEFORE IT WAS FIXED. Twenty failed lines moved the Stack Pointer from FFFD to FE6D, and it only ever went one way. Nothing had noticed because it takes thousands of failures to reach anything and nobody types thousands of anything. A loop in a script would, which is why this is worth doing before there are loops rather than after. So the loop starts each turn from a known place. SystemStack is NOT that place: it is taken when a program starts, so that the shell's Stack can be given back when the program stops - which means it holds wherever the shell had got to at that moment, the value that needs correcting rather than the one to correct from. ShellStack is taken once, at boot, when nothing is happening. Second use of MVDS in the system, and it earns it for the same reason as the first: a Stack that is right by construction beats one that is right because everybody remembered. Break prints the registers, so the test is two dumps with eight failures between them and a requirement that they agree. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
a8707f29f0 |
Names for things
"set apps /Apps", and then "$apps" anywhere on a later line stands for it. A name stops where a name stops - letters and digits - so it composes into a path without anything having to be quoted, which is the whole reason a script would want one. THE SUBSTITUTION HAPPENS ON EVERY LINE THE SHELL IS ABOUT TO RUN, typed or read out of a file, so the two behave the same and no command below has to know that variables exist. Same shape as the line editing: one place the whole system already flows through, rather than a decision made twenty times. A NAME NOTHING WAS SET TO DOES NOT RUN THE LINE. Every other shell expands it to nothing, and that is the wrong answer here: a mistyped name would quietly become an empty path, which is the class of silent wrong answer the rest of this system spends its effort refusing. It says so and the line counts as failed, which stops a script - and the test proves that by running one, where the line after it must not appear. Somebody who wants an empty value writes "set name" and gets one, so the escape hatch exists and has to be asked for. A NAME TOO LONG IS AN ERROR RATHER THAN A SHORTER NAME. Cutting it off at fifteen characters was the first version, and it is the same fault wearing a different coat: two names differing only after the fifteenth would be one variable, and the complaint about a missing one printed a word nobody typed. Eight slots of sixty four bytes - sixteen of name, forty eight of value - and sixty four rather than eighty because A and B are a sixteen bit shift register, so two rotations turn a slot number into its offset. The same trick the history uses, and the reason neither needs a multiply this machine has not got. TWO THINGS I GOT WRONG AND ONE I FOUND: doSetVar ended in RET. It is BRANCHED to from the dispatch, not called, so that RET went wherever the Stack happened to point - the same fault that formatted a disk last week, in a command written three days after the rule was named. The new lint rule does not catch this shape: it fires on falling INTO a subroutine, not on a branch target that ends like one. And a test of the expansion's answer, which is dead code: commandFailed does not return. It marks the line and branches to the prompt, the way every failure in this shell is reported, so the only way out of the expansion is the one where it worked. Which turned up a real leak, measured and not yet fixed: every failure that goes through commandFailed abandons the frames between the prompt and the call. SP goes from FFFD to FE6D over twenty of them, twenty bytes each. Its own commit. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
3c76934a9a |
Tab reaches the disk
Paths and programs, which is the half that makes it worth having. The first word of a line is a command or a PROGRAM, offered under the name somebody would type - the extension taken off - and anything after it is a file, offered as it really is. A separator anywhere in the word says which directory to look in. A directory answers with a separator on the end instead of a space, which says what it is and lets the next part be typed straight away. The answer ending in one is also what stops a space being added, so that is one test rather than a flag. PROGRAMS ARE LOOKED FOR WHERE THE SHELL WOULD LOOK to run one: where you are, /Apps on the disk you are on, and /Apps on drive 0. Offering something the shell would not find would be finishing a word into a thing that then does not work. Drive 0's is skipped when that is already the drive, or every program in it would be offered twice and nothing would ever be the only match. Walking somebody else's directory means standing in it, which is the only way to walk one here, so where the person was and which drive they were on are put down first and restored whatever happens. Three bugs, all found by running it: THE DIRECTORY TEST WAS INVERTED. dir asks the same question the same way round four hundred lines further up, which is what made it obvious once looked at. THE /Apps WALK OVERWROTE THE TYPED PATH. The whole search runs a second time to list the matches, and by then TabDir said "/Apps" - so a word that had named nowhere went looking in the wrong place and listed nothing at all. Two ways into the walk now, and the typed path is never written over. AND LISTING ONLY KNEW ABOUT COMMANDS, because it was a second copy of the walk. It is the same walk with a flag now: finding the answer and showing the matches are the same question asked twice. Also cosmosMonitor, which had been RE-BLESSED INTO MEANINGLESSNESS by the wall move. It disassembles a loaded program, at an address the input names - and that address moved a page while the recording was simply re-recorded to whatever came out, which was a page of zeroes. It is pointed at 5000 again. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
bb065fe221 |
Tab finishes a word somebody started
The first word of a line, against the shell's fifteen commands. One match goes in with a space after it, because a word that can only be one thing is finished. Several are folded into their longest common prefix and that goes in, which is the most that can be said without guessing which was meant - and if that adds nothing, the matches are listed and the line put back underneath. THE LINE COMING BACK IS THE HALF I EXPECTED TO BE HARD and it was already solved. The prompt has been reprinted somewhere else entirely, so the editor's idea of where the line begins is wrong - but editAnchor works that out backwards from where printing ended, precisely so it survives the screen moving. Listing is a redraw it already knew how to do. editInsert became editPut, a routine, because completing a word puts in several characters and every one of them is that. Which cost a bug immediately: the old inline code left the insertion point in A, and a RET puts A back to what the caller had. Two more bugs worth naming, both mine and both the same shape - a pointer that had moved: THE CANDIDATE'S START HAS TO BE KEPT. The comparison walks DP3 through the name as it matches, so by the time a match is declared, DP3 points at the part AFTER what was typed - and that is what got copied. "he" completed to "he" because the answer taken was "lp". AND THE INSERTION STOPS AT OR PAST, not exactly equal. With the wrong answer the two counters passed each other and the loop ran off the end of the buffer, filling the line with whatever was next in memory. They cannot pass each other now, and the branch stays, because the cheaper failure is worth nothing. MY OWN TEST HAD A HOLE and breaking the code found it. The later-word case pressed Tab after a space, where there is nothing to finish anyway, so it passed whether or not the shell checked which word it was on. It types "echo he" now, which would become "echo help" if it did not. The assembler's label table went past 1024 and is doubled. A ceiling reached once will be reached again, and it is pointers into source already in memory. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
749fef8ce2 |
The shell's own words, as a table and not just a chain
The dispatch is a run of "is the line this name" comparisons. That is fine to execute and impossible to WALK, and completing a half typed command needs to walk them - so the names have to be data as well as code. They nearly were already: DirName through ExitName were fourteen zero terminated strings sitting back to back, which is a table by accident of layout. This makes it deliberate. MonitorName joins them, the run is labelled, and a count goes underneath because a run of strings does not say where it stops. WHAT MAKES IT A TABLE IS THE ZEROES. Each name ends in one, so the next begins after it: no pointers, no lengths, and adding a command costs a line. Tests/docs.sh reads both the dispatch and the run and compares them, because the two can disagree and every way they do is quiet. A command added to the dispatch and not to the run simply never completes, which nobody would think to check by hand. Something put BETWEEN the strings is worse: the walk ends there and takes every command after it, and the machine goes on working perfectly except that Tab knows about six things instead of fifteen. All three break that way and say something useful. Putting one byte in the middle of the run reports that it holds ten names against the fifteen claimed, which points at roughly where. Groundwork for Tab completion. Nothing uses it yet. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |
||
|
AnachronautandClaude Opus 5
|
b04e4b7d1c |
Finish making the tune a program
The user's conversion, which I reverted while I was working out whether it was half done or broken. It was half done: an sbx application wants its #Include above #Program, because services.asm ends in a #Vectors block and a #Base written after that has no segment to be the base of. So the include moves up, the bases move a page with everything else, and the test starts it from the shell instead of booting it. It plays for 9,469,987 cycles, 9,423,527 of them waiting, which is the same 567 frames of music it played as a boot image. BEING A PROGRAM MEANS ITS VECTOR IS THE SYSTEM'S TO INSTALL. It brings the screen's, so that it has a beat to play to, and CosmOS puts it in when the tune starts and takes it back out when it stops - a thing a boot image never had to have right, and the second program here to exercise the version two format at all. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW |