Skip to navigation

Elite on the BBC Micro

Workspaces: WP (Master version)

Name: WP [View in context] Type: Workspace [Compare versions] Address: &0E41 to &12A9 Category: Workspaces Summary: Ship slots, variables
ORG &0E41 .WP SKIP 0 \ The start of the WP workspace .FRIN SKIP NOSH + 1 \ Slots for the ships in the local bubble of universe \ \ There are #NOSH + 1 slots, but the ship-spawning \ routine at NWSHP only populates #NOSH of them, so \ (the last slot is effectively used as a null \ terminator when shuffling the slots down in the \ KILLSHP routine) \ \ See the deep dive on "The local bubble of universe" \ for details of how Elite stores the local universe in \ FRIN, UNIV and K% .MANY SKIP SST \ The number of ships of each type in the local bubble \ of universe \ \ The number of ships of type X in the local bubble is \ stored at MANY+X, so the number of Sidewinders is at \ MANY+1, the number of Mambas is at MANY+2, and so on \ \ See the deep dive on "Ship blueprints" for a list of \ ship types .SSPR SKIP NTY + 1 - SST \ "Space station present" flag \ \ * Non-zero if we are inside the space station's safe \ zone \ \ * 0 if we aren't (in which case we can show the sun) \ \ This flag is at MANY+SST, which is no coincidence, as \ MANY+SST is a count of how many space stations there \ are in our local bubble, which is the same as saying \ "space station present" .JUNK SKIP 1 \ The amount of junk in the local bubble \ \ "Junk" is defined as being one of these: \ \ * Escape pod \ * Alloy plate \ * Cargo canister \ * Asteroid \ * Splinter \ * Shuttle \ * Transporter .auto SKIP 1 \ Docking computer activation status \ \ * 0 = Docking computer is off \ \ * Non-zero = Docking computer is running .ECMP SKIP 1 \ Our E.C.M. status \ \ * 0 = E.C.M. is off \ \ * Non-zero = E.C.M. is on .MJ SKIP 1 \ Are we in witchspace (i.e. have we mis-jumped)? \ \ * 0 = no, we are in normal space \ \ * &FF = yes, we are in witchspace .CABTMP SKIP 1 \ Cabin temperature \ \ The ambient cabin temperature in deep space is 30, \ which is displayed as one notch on the dashboard bar \ \ We get higher temperatures closer to the sun \ \ CABTMP shares a location with MANY, but that's OK as \ MANY+0 would contain the number of ships of type 0, \ and as there is no ship type 0 (they start at 1), the \ byte at MANY+0 is not used for storing a ship type \ and can be used for the cabin temperature instead .LAS2 SKIP 1 \ Laser power for the current laser \ \ * Bits 0-6 contain the laser power of the current \ space view \ \ * Bit 7 denotes whether or not the laser pulses: \ \ * 0 = pulsing laser \ \ * 1 = beam laser (i.e. always on) .MSAR SKIP 1 \ The targeting state of our leftmost missile \ \ * 0 = missile is not looking for a target, or it \ already has a target lock (indicator is not \ yellow/white) \ \ * Non-zero = missile is currently looking for a \ target (indicator is yellow/white) .VIEW SKIP 1 \ The number of the current space view \ \ * 0 = front \ * 1 = rear \ * 2 = left \ * 3 = right .LASCT SKIP 1 \ The laser pulse count for the current laser \ \ This is a counter that defines the gap between the \ pulses of a pulse laser. It is set as follows: \ \ * 0 for a beam laser \ \ * 10 for a pulse laser \ \ It gets decremented every vertical sync (in the LINSCN \ routine, which is called 50 times a second) and is set \ to a non-zero value for pulse lasers only \ \ The laser only fires when the value of LASCT hits \ zero, so for pulse lasers with a value of 10, that \ means the laser fires once every 10 vertical syncs (or \ 5 times a second) \ \ In comparison, beam lasers fire continuously as the \ value of LASCT is always 0 .GNTMP SKIP 1 \ Laser temperature (or "gun temperature") \ \ If the laser temperature exceeds 242 then the laser \ overheats and cannot be fired again until it has \ cooled down .HFX SKIP 1 \ A flag that toggles the hyperspace colour effect \ \ * 0 = no colour effect \ \ * Non-zero = hyperspace colour effect enabled \ \ When HFX is set to 1, the mode 1 screen that makes \ up the top part of the display is temporarily switched \ to mode 2 (the same screen mode as the dashboard), \ which has the effect of blurring and colouring the \ hyperspace rings in the top part of the screen. The \ code to do this is in the LINSCN routine, which is \ called as part of the screen mode routine at IRQ1. \ It's in LINSCN that HFX is checked, and if it is \ non-zero, the top part of the screen is not switched \ to mode 1, thus leaving the top part of the screen in \ the more colourful mode 2 .EV SKIP 1 \ The "extra vessels" spawning counter \ \ This counter is set to 0 on arrival in a system and \ following an in-system jump, and is bumped up when we \ spawn bounty hunters or pirates (i.e. "extra vessels") \ \ It decreases by 1 each time we consider spawning more \ "extra vessels" in part 4 of the main game loop, so \ increasing the value of EV has the effect of delaying \ the spawning of more vessels \ \ In other words, this counter stops bounty hunters and \ pirates from continually appearing, and ensures that \ there's a delay between spawnings .DLY SKIP 1 \ In-flight message delay \ \ This counter is used to keep an in-flight message up \ for a specified time before it gets removed. The value \ in DLY is decremented each time we start another \ iteration of the main game loop at TT100 .de SKIP 1 \ Equipment destruction flag \ \ * Bit 1 denotes whether or not the in-flight message \ about to be shown by the MESS routine is about \ destroyed equipment: \ \ * 0 = the message is shown normally \ \ * 1 = the string " DESTROYED" gets added to the \ end of the message .LSX2 SKIP 256 \ The ball line heap for storing x-coordinates (see the \ deep dive on "The ball line heap" for details) .LSY2 SKIP 256 \ The ball line heap for storing y-coordinates (see the \ deep dive on "The ball line heap" for details) .LSO SKIP 200 \ This space has two uses: \ \ * The ship line heap for the space station (see \ NWSPS for details) \ \ * The sun line heap (see SUN for details) \ \ The spaces can be shared as our local bubble of \ universe can support either the sun or a space \ station, but not both .BUF SKIP 90 \ The line buffer used by DASC to print justified text .SX SKIP NOST + 1 \ This is where we store the x_hi coordinates for all \ the stardust particles .SXL SKIP NOST + 1 \ This is where we store the x_lo coordinates for all \ the stardust particles .SY SKIP NOST + 1 \ This is where we store the y_hi coordinates for all \ the stardust particles .SYL SKIP NOST + 1 \ This is where we store the y_lo coordinates for all \ the stardust particles .SZ SKIP NOST + 1 \ This is where we store the z_hi coordinates for all \ the stardust particles .SZL SKIP NOST + 1 \ This is where we store the z_lo coordinates for all \ the stardust particles .LASX SKIP 1 \ The x-coordinate of the tip of the laser line .LASY SKIP 1 \ The y-coordinate of the tip of the laser line SKIP 1 \ This byte appears to be unused .ALTIT SKIP 1 \ Our altitude above the surface of the planet or sun \ \ * 255 = we are a long way above the surface \ \ * 1-254 = our altitude as the square root of: \ \ x_hi^2 + y_hi^2 + z_hi^2 - 6^2 \ \ where our ship is at the origin, the centre of the \ planet/sun is at (x_hi, y_hi, z_hi), and the \ radius of the planet/sun is 6 \ \ * 0 = we have crashed into the surface .SWAP SKIP 1 \ Temporary storage, used to store a flag that records \ whether or not we had to swap a line's start and end \ coordinates around when clipping the line in routine \ LL145 (the flag is used in places like BLINE to swap \ them back) SKIP 6 \ These bytes appear to be unused .SDIST SKIP 1 \ Used to store the nearest distance of the rotating \ ship on the title screen SKIP 2 \ These bytes appear to be unused IF _COMPACT .NMI SKIP 1 \ Used to store the ID of the current owner of the NMI \ workspace in the NMICLAIM routine, so we can hand it \ back to them in the NMIRELEASE routine once we are \ done using it ENDIF .NAME SKIP 8 \ The current commander name \ \ The commander name can be up to 7 characters (the DFS \ limit for file names), and is terminated by a carriage \ return .TP SKIP 1 \ The current mission status \ \ * Bits 0-1 = Mission 1 status \ \ * %00 = Mission not started \ * %01 = Mission in progress, hunting for ship \ * %11 = Constrictor killed, not debriefed yet \ * %10 = Mission and debrief complete \ \ * Bits 2-3 = Mission 2 status \ \ * %00 = Mission not started \ * %01 = Mission in progress, plans not picked up \ * %10 = Mission in progress, plans picked up \ * %11 = Mission complete .QQ0 SKIP 1 \ The current system's galactic x-coordinate (0-256) .QQ1 SKIP 1 \ The current system's galactic y-coordinate (0-256) .QQ21 SKIP 6 \ The three 16-bit seeds for the current galaxy \ \ These seeds define system 0 in the current galaxy, so \ they can be used as a starting point to generate all \ 256 systems in the galaxy \ \ Using a galactic hyperdrive rotates each byte to the \ left (rolling each byte within itself) to get the \ seeds for the next galaxy, so after eight galactic \ jumps, the seeds roll around to the first galaxy again \ \ See the deep dives on "Galaxy and system seeds" and \ "Twisting the system seeds" for more details .CASH SKIP 4 \ Our current cash pot \ \ The cash stash is stored as a 32-bit unsigned integer, \ with the most significant byte in CASH and the least \ significant in CASH+3. This is big-endian, which is \ the opposite way round to most of the numbers used in \ Elite - to use our notation for multi-byte numbers, \ the amount of cash is CASH(0 1 2 3) .QQ14 SKIP 1 \ Our current fuel level (0-70) \ \ The fuel level is stored as the number of light years \ multiplied by 10, so QQ14 = 1 represents 0.1 light \ years, and the maximum possible value is 70, for 7.0 \ light years .COK SKIP 1 \ Flags used to generate the competition code \ \ See the deep dive on "The competition code" for \ details of these flags and how they are used in \ generating and decoding the competition code .GCNT SKIP 1 \ The number of the current galaxy (0-7) \ \ When this is displayed in-game, 1 is added to the \ number, so we start in galaxy 1 in-game, but it's \ stored as galaxy 0 internally \ \ The galaxy number increases by one every time a \ galactic hyperdrive is used, and wraps back round to \ the start after eight galaxies .LASER SKIP 4 \ The specifications of the lasers fitted to each of the \ four space views: \ \ * Byte #0 = front view (red key f0) \ * Byte #1 = rear view (red key f1) \ * Byte #2 = left view (red key f2) \ * Byte #3 = right view (red key f3) \ \ For each of the views: \ \ * 0 = no laser is fitted to this view \ \ * Non-zero = a laser is fitted to this view, with \ the following specification: \ \ * Bits 0-6 contain the laser's power \ \ * Bit 7 determines whether or not the laser pulses \ (0 = pulse or mining laser) or is always on \ (1 = beam or military laser) SKIP 2 \ These bytes appear to be unused (they were originally \ used for up/down lasers, but they were dropped) .CRGO SKIP 1 \ Our ship's cargo capacity \ \ * 22 = standard cargo bay of 20 tonnes \ \ * 37 = large cargo bay of 35 tonnes \ \ The value is two greater than the actual capacity to \ male the maths in tnpr slightly more efficient .QQ20 SKIP 17 \ The contents of our cargo hold \ \ The amount of market item X that we have in our hold \ can be found in the X-th byte of QQ20. For example: \ \ * QQ20 contains the amount of food (item 0) \ \ * QQ20+7 contains the amount of computers (item 7) \ \ See QQ23 for a list of market item numbers and their \ storage units .ECM SKIP 1 \ E.C.M. system \ \ * 0 = not fitted \ \ * &FF = fitted .BST SKIP 1 \ Fuel scoops (BST stands for "barrel status") \ \ * 0 = not fitted \ \ * &FF = fitted .BOMB SKIP 1 \ Energy bomb \ \ * 0 = not fitted \ \ * &7F = fitted .ENGY SKIP 1 \ Energy unit \ \ * 0 = not fitted \ \ * 1 = fitted .DKCMP SKIP 1 \ Docking computer \ \ * 0 = not fitted \ \ * &FF = fitted .GHYP SKIP 1 \ Galactic hyperdrive \ \ * 0 = not fitted \ \ * &FF = fitted .ESCP SKIP 1 \ Escape pod \ \ * 0 = not fitted \ \ * &FF = fitted SKIP 1 \ This byte appears to be unused .TRUMBLE SKIP 2 \ The number of Trumbles in the cargo hold \ \ The Master version doesn't actually haveTrumbles, but \ the Trumble code from the other versions was kept when \ the Master version was put together .TALLYF SKIP 1 \ Combat rank fraction \ \ Contains the fraction part of the kill count, which \ together with the integer in TALLY(1 0) determines our \ combat rank. The fraction is stored as the numerator \ of a fraction with a denominator of 256, so a TALLYF \ of 128 would represent 0.5 (i.e. 128 / 256) .NOMSL SKIP 1 \ The number of missiles we have fitted (0-4) .FIST SKIP 1 \ Our legal status (FIST stands for "fugitive/innocent \ status"): \ \ * 0 = Clean \ \ * 1-49 = Offender \ \ * 50+ = Fugitive \ \ You get 64 points if you kill a cop, so that's a fast \ ticket to fugitive status .AVL SKIP 17 \ Market availability in the current system \ \ The available amount of market item X is stored in \ the X-th byte of AVL, so for example: \ \ * AVL contains the amount of food (item 0) \ \ * AVL+7 contains the amount of computers (item 7) \ \ See QQ23 for a list of market item numbers and their \ storage units, and the deep dive on "Market item \ prices and availability" for details of the algorithm \ used for calculating each item's availability .QQ26 SKIP 1 \ A random value used to randomise market data \ \ This value is set to a new random number for each \ change of system, so we can add a random factor into \ the calculations for market prices (for details of how \ this is used, see the deep dive on "Market prices") .TALLY SKIP 2 \ Our combat rank \ \ The combat rank is stored as the number of kills, in a \ 16-bit number TALLY(1 0) - so the high byte is in \ TALLY+1 and the low byte in TALLY \ \ There is also a fractional part of the kill count, \ which is stored in TALLYF \ \ If the high byte in TALLY+1 is 0 then we have between \ 0 and 255 kills, so our rank is Harmless, Mostly \ Harmless, Poor, Average or Above Average, according to \ the value of the low byte in TALLY: \ \ Harmless = %00000000 to %00000011 = 0 to 3 \ Mostly Harmless = %00000100 to %00000111 = 4 to 7 \ Poor = %00001000 to %00001111 = 8 to 15 \ Average = %00010000 to %00011111 = 16 to 31 \ Above Average = %00100000 to %11111111 = 32 to 255 \ \ If the high byte in TALLY+1 is non-zero then we are \ Competent, Dangerous, Deadly or Elite, according to \ the high byte in TALLY+1: \ \ Competent = 1 = 256 to 511 kills \ Dangerous = 2 to 9 = 512 to 2559 kills \ Deadly = 10 to 24 = 2560 to 6399 kills \ Elite = 25 and up = 6400 kills and up \ \ You can see the rating calculation in STATUS .SVC SKIP 1 \ The save count \ \ When a new commander is created, the save count gets \ set to 128. This value gets halved each time the \ commander file is saved, but it is otherwise unused. \ It is presumably part of the security system for the \ competition, possibly another flag to catch out \ entries with manually altered commander files SKIP 2 \ The commander file checksum \ \ These two bytes are reserved for the commander file \ checksum, so when the current commander block is \ copied from here to the last saved commander block at \ NA%, CHK and CHK2 get overwritten NT% = SVC + 3 - TP \ This sets the variable NT% to the size of the current \ commander data block, which starts at TP and ends at \ SVC+3 (inclusive), i.e. with the last checksum byte SKIP 1 \ This byte appears to be unused .MCH SKIP 1 \ The text token number of the in-flight message that is \ currently being shown, and which will be removed by \ the me2 routine when the counter in DLY reaches zero .COMX SKIP 1 \ The x-coordinate of the compass dot .COMY SKIP 1 \ The y-coordinate of the compass dot SKIP 14 \ These bytes appear to be unused .QQ24 SKIP 1 \ Temporary storage, used to store the current market \ item's price in routine TT151 .QQ25 SKIP 1 \ Temporary storage, used to store the current market \ item's availability in routine TT151 .QQ28 SKIP 1 \ Temporary storage, used to store the economy byte of \ the current system in routine var .QQ29 SKIP 1 \ Temporary storage, used in a number of places .gov SKIP 1 \ The current system's government type (0-7) \ \ See the deep dive on "Generating system data" for \ details of the various government types .tek SKIP 1 \ The current system's tech level (0-14) \ \ See the deep dive on "Generating system data" for more \ information on tech levels .SLSP SKIP 2 \ The address of the bottom of the ship line heap \ \ The ship line heap is a descending block of memory \ extended downwards by the NWSHP routine when adding \ new ships (and their associated ship line heaps), in \ which case SLSP is lowered to provide more heap space, \ assuming there is enough free memory to do so .QQ2 SKIP 6 \ The three 16-bit seeds for the current system, i.e. \ the one we are currently in \ \ See the deep dives on "Galaxy and system seeds" and \ "Twisting the system seeds" for more details .safehouse SKIP 6 \ Backup storage for the seeds for the selected system \ \ The seeds for the current system get stored here as \ soon as a hyperspace is initiated, so we can fetch \ them in the hyp1 routine. This fixes a bug in an \ earlier version where you could hyperspace while \ docking and magically appear in your destination \ station .CLCNT SKIP 1 \ Used to store the number of particles in the explosion \ cloud, though the number is never actually used .ADCH1 SKIP 1 \ Contains the high byte of the latest value from ADC \ channel 1 (the joystick X value), which gets updated \ regularly by the IRQ1 interrupt handler .ADCH2 SKIP 1 \ Contains the high byte of the latest value from ADC \ channel 2 (the joystick Y value), which gets updated \ regularly by the IRQ1 interrupt handler .ADCH3 SKIP 1 \ Contains the high byte of the latest value from ADC \ channel 3 (the Bitstik rotation value), which gets \ updated regularly by the IRQ1 interrupt handler PRINT "WP workspace from ", ~WP," to ", ~P%