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pathfindingworking on pathfinding in the game. here is Russian description of Lee's algorithm: [url]http://algolist.manual.ru/games/wavealg.php[/url] "if-then"…
... implementation would use a 256-aligned area of 256 bytes, with register HL ... HL/DE, or storing 2 bytes instead of 1, it won ... -
pathfindingworking on pathfinding in the game. here is Russian description of Lee's algorithm: [url]http://algolist.manual.ru/games/wavealg.php[/url] "if-then"…
[QUOTE=Patrik Rak;700143][QUOTE=Einar Saukas;700130]The problem is, you are applying asymptotic analysis to a limited size problem (i.e levels limited to size 24x32). Therefore the value of these constants make all the difference.[/QUOTE]
Not ... -
Z80 internal compressionThis isn't exactly a ZX Spectrum problem, but since WOS probably has some of the best Z80 coders in the world, I thought I might ask anyway. For my …
... content. Buffer can be 256 bytes to 2k bytes. I'll replace that ... -
Z80 internal compressionThis isn't exactly a ZX Spectrum problem, but since WOS probably has some of the best Z80 coders in the world, I thought I might ask anyway. For my …
... the last segment and copy 256 bytes of garbage at the end ... lengths - 1, 2 or 3 bytes in 4*2 bits. 1 ... entries just hold the plain bytes; 3-byte entries hold a ... -
Varios +3(e)DOS questions?I'm converting tape games to disk, for being used in my +3e. I'm trying to convert them to standard BASIC loaders, so files could be copied using BAS…
[QUOTE=Zup;700779]And a question related to commercial loaders. Because I'm being unable to crack some loaders (speedlock, etc.), I was thinking about attacking disk loaders. How did they read the disk? Did they use +3DOS calls or did they access the ... -
Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
... setting H=0 and L=256 byte index but you are ... to just one page of 256 bytes. You're a little slower ... -
Shifting the UDG pointer from a MC loop...I have got myself in a bit of a mess again, I am trying to write a machine code subroutine that shifts the udg pointer (23675) up 64 places then shif…
Shouldn't the UDG banks be 168 bytes apart, not 128, as 21*8=168?
As it is, I'd set them 256 bytes apart and then just do:
LD HL,23676 : INC (HL) -
Where do you stick the stack?...OK, so I've got a fair chunk of ASM code assembled from 24000 mark. The stack shouldn't get very big, just a few PUSHes and POPs of the main regis…
Ideally you want the stack in fast RAM. On the 128 I'd say it's actually better to put it 256 bytes above slow RAM. In the worst case the stack will grow down into slow RAM, but it won't overflow. -
Where do you stick the stack?...OK, so I've got a fair chunk of ASM code assembled from 24000 mark. The stack shouldn't get very big, just a few PUSHes and POPs of the main regis…
... SP,$5BFF and use the 256 bytes in the unused area between ... you don't need a 256 byte interrupt table as the ... -
Tape loading - blocks with checksumThese were sometimes used for 128K games and had a searching / loading message, ie. Loading Block 08, then if a block didn't load right one could rew…
... in block of up to 256 bytes. If an unrecognised block is ... save the screen as 27 256-byte blocks, and load it ... -
How to get 720KB on Opus Discovery floppy (using PC drive)I upgraded an Opus Discovery yesterday with a PC drive, but I'm looking for the way to get a floppy formatted as 720KB. If I understand other topics…
... handling the fetching of 512 bytes sectors (1-9) all by ... , and the sending out of 256 bytes sectors (0-17), or whatever ... -
Scrolling by 2 pixelsWhat is the fastest way of scrolling a Spectrum screen line by 2 pixels left or right? When thinking about it I've come to this simple solution: [C…
[QUOTE=Ralf;716119]Yes, it could work if we make sure to keep in 256 byte bonduaries.[/QUOTE]
Column coordinates within the Spectrum screen always respect the 256 bytes boundary. -
Scrolling by 2 pixelsWhat is the fastest way of scrolling a Spectrum screen line by 2 pixels left or right? When thinking about it I've come to this simple solution: [C…
... Spectrum screen always respect the 256 bytes boundary.[/QUOTE]
S- are bytes actually copied to real screen ... need to be 32 bytes, I can make it ... is 28 screen bytes + 2 N bytes on right side ... I can spare this 768 bytes :)
Left ... -
Movin And A Groovin Horizontal Flip improvementOn the left is the flip horizontal portion from Andy Pennell'S excellent Movin' & a Groovin' machine code screen routines from Your Spectrum #19 (Oct…
... lookup table to 256 byte boundary (requires 256 bytes of free space whilst ... C9
;17 bytes
256 byte table will look ... -
Movin And A Groovin Horizontal Flip improvementOn the left is the flip horizontal portion from Andy Pennell'S excellent Movin' & a Groovin' machine code screen routines from Your Spectrum #19 (Oct…
Yes, lookup table is only 256 bytes and makes everything much faster. Every serious game uses it. -
Movin And A Groovin Horizontal Flip improvementOn the left is the flip horizontal portion from Andy Pennell'S excellent Movin' & a Groovin' machine code screen routines from Your Spectrum #19 (Oct…
[QUOTE=jamorski;718534]The old size vs speed chestnut eh!![/QUOTE]
Right! :)
When optimizing for size, the next step would be eliminating the 256 bytes lookup table.... -
Experimenting with turboloadersHello, My first post, having lurked here for a while. I'm a lifelong computer nerd, Spectrum fan since childhood in the eighties, and have recently…
... starts a new block every 256 bytes (thats the 'tick' you hear ... -
MC LPRINT 23681Having problems with this routine to print large on the screen using LPRINT, it works ok in BASIC, but cant seem to get it to loop for some reason in…
... the display, simply ldir the 256 bytes over the next 7 scan ... /> ld bc, 0x0700 ; copies 2048-256 bytes.
ldir
ret
128 BASIC-compatible way of loading BASIC as code?On a 48K Speccy (or from 48 BASIC or USR 0 mode on a 128K machine), one can do a silly trick like this: [code];; load a 4000 byte BASIC program ld i…
Dunno if it would work, BUT- save all the system variables except the first 256 bytes that is the original printer buffer area. On the +3 (so I assume the 128 too), that space is used for paging the RAM, so yeah. Speccy 128 would act up a little.128 BASIC-compatible way of loading BASIC as code?On a 48K Speccy (or from 48 BASIC or USR 0 mode on a 128K machine), one can do a silly trick like this: [code];; load a 4000 byte BASIC program ld i…
... system variables except the first 256 bytes that is the original printer ...JSW2 - Game Loader DifferencesThere are three official releases of JSW2. I'm not counting the 'JSW2-128' version here as far as I'm aware this was not in any way 'official' as it …
... , 800 ; 22529 to 23329 (800 bytes) which extends into the basic ... /> [/QUOTE]
801 bytes (technically the number of bytes that are zeroed ... anyway (note: attribute file = 768 bytes; printer buffer = 256 bytes).Experimenting with turboloadersHello, My first post, having lurked here for a while. I'm a lifelong computer nerd, Spectrum fan since childhood in the eighties, and have recently…
... you have). Afterwards the next 256 bytes are reserved for ZX BASIC ...Manic Miner ZX81Hi Guys, Can anyone explain why [url=http://www.worldofspectrum.org/infoseekid.cgi?id=0017539]Manic Miner ZX81[/url] is not able to reproduce the ex…
... entire memorybuffer is just 200 bytes.
The second game ... ) has also a maximum of 256 bytes data, but uses a counter ...Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... code copies some bytes, then goes 256 bytes higher and does ... you add some offset bytes and repeat the job in ... [I]target+0
target+256
target+512
target ... +14
target+0+256+14
target+0+ ... +28
target+0+256+28
target+0+ ...Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... unrolled code copies some bytes, then goes 256 bytes higher and does this ... . Then you add some offset bytes and repeat the job in ...
