Search found 734 matches

by Lethargeek
Tue Dec 19, 2023 5:38 pm
Forum: Games/Software
Topic: Zaxxon, should have been better for 1985
Replies: 24
Views: 1036

Re: Zaxxon, should have been better for 1985

Would doing a circular buffer help, I don't think a game looking like Zaxxon even needs an actual scrolling. Eg Commando has no real scrolling nor a buffer, but lots of unrolled separate subroutines for almost every type (even a typesize) of bg object, and lots of specialized subroutines for the sa...
by Lethargeek
Tue Dec 19, 2023 11:11 am
Forum: Games/Software
Topic: Zaxxon, should have been better for 1985
Replies: 24
Views: 1036

Re: Zaxxon, should have been better for 1985

No. Commando and Critical Mass were released in November 1985 and were, with the exception of Nigel Alderton's work on Street Hawk, the developers only releases of the year. In contrast, Platinum Productions released eight titles in 1985 from Zaxxon in January to any-direction scrolling Rambo in No...
by Lethargeek
Mon Dec 18, 2023 9:15 pm
Forum: Games/Software
Topic: Zaxxon, should have been better for 1985
Replies: 24
Views: 1036

Re: Zaxxon, should have been better for 1985

It's easy to say from the safe and cozy vantage point of 2023, with nearly 4 decades of hindsight under the belt. But could it really? It's a somewhat unfair assertion, since the realities of game development were really much different back then, and also the situation and skills of various coders/...
by Lethargeek
Wed Dec 13, 2023 4:54 am
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

If they had wanted to compete in the computer gaming market they would have produced a different computer. That's obvious. well, then they failed in whatever market they aimed, that's obvious :) Another design choice which reflects their interest in text applications is the way the screen pixels ar...
by Lethargeek
Wed Dec 13, 2023 4:38 am
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

At the end of the day, it is. There's no two ways about this. The original programmer had absolutely no way of expressing their intent and so any hardware is guessing. Even if you code specific rules for every single individual game, this is still guesswork about what the original programmer would ...
by Lethargeek
Tue Dec 12, 2023 1:46 pm
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

Better for what? for overall user experience This computer wasn't made for games although that's what it ended being most used for. It was the best and the cheapest for the task Sinclair had in mind. you can't be sure what exactly Sinclair had in his mind And let's not forget it was a success. and ...
by Lethargeek
Tue Dec 12, 2023 12:51 pm
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

AndyC wrote: Tue Dec 12, 2023 11:32 am Sure, but then you get "fat pixels"
just like many other systems games asking to be ported/converted ;)
by Lethargeek
Tue Dec 12, 2023 12:49 pm
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

ULAX is, as far as old software not written for it, entirely based on guesswork. Sure it's educated guesswork, based on studying lots of existing code, but it's still seeing a sequence of changes and makinba big assumption about what the end result should be on screen as a result. And any system th...
by Lethargeek
Tue Dec 12, 2023 11:08 am
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

About the only practical option for an upgrade would have been to add a Timex-style 8x1 attribute mode (with maybe, at a stretch, two BRIGHT bits or half-green bits to expand the palette) on the 128K's ULA. This wouldn't eliminate colour clash, but would allow for more colourful games. The very min...
by Lethargeek
Tue Dec 12, 2023 10:52 am
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

Well the expansion port is essentially all the signals from the Z80 Plus a few extra bits. You could theoretically add just about anything too it. But you'd have to write entirely new software for it. There isn't any capacity in how the spectrum actually stores "what is on the screen" to ...
by Lethargeek
Tue Dec 12, 2023 10:39 am
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

Everything on 8-bit machines was an active compromise somewhere. You could use a lot of screen RAM and take the hit on performance, like the CPC. Or you could go for a mostly text/tile oriented display like the C64, but pay the price in terms of flexibility to some extent. doesn't mean better compr...
by Lethargeek
Tue Dec 12, 2023 8:55 am
Forum: Hardware
Topic: Colour clash query
Replies: 52
Views: 1589

Re: Colour clash query

Memory is one reason. Very first Spectrums only had 16K. Also, completely eliminating color clash would increase traffic between ULA and lower RAM - more delays for CPU 4-colours no-attribute mode (similar to what cpc had) would have the same amount of traffic hovewer, 12k just for the screen was o...
by Lethargeek
Sat Dec 09, 2023 6:37 pm
Forum: Programming
Topic: Forth compiler for ZX
Replies: 67
Views: 2188

Re: Forth compiler for ZX

@_dw, i mean, even your _fib2 here (being "n1 -- n2") could be SCALL
by Lethargeek
Sat Dec 09, 2023 5:07 pm
Forum: Programming
Topic: Forth compiler for ZX
Replies: 67
Views: 2188

Re: Forth compiler for ZX

some possible optimizations a) keeping track what stack values happened to be in registers when they are needed, thus avoiding some explicit redundant swap/drop/rot/etc b) for simple functions taking and returning 1-2 or no values instead of "call...jp" use "pop:(pop):call...ret"...
by Lethargeek
Wed Dec 06, 2023 8:19 pm
Forum: Games/Software
Topic: What's the SHORTEST Speccy game ever?
Replies: 54
Views: 2516

Re: What's the SHORTEST Speccy game ever?

Lee Bee wrote: Wed Dec 06, 2023 6:45 pm SQIJ is a pretty short game. Here's a re-post of my complete game map:

Image
but you can't finish it, so it's actually the longest one :P
by Lethargeek
Wed Dec 06, 2023 8:16 pm
Forum: Games/Software
Topic: Games where the main sprite changes
Replies: 37
Views: 1183

Re: Games where the main sprite changes

Transformers , rather obviously! And I think the thing in Jet Set Willy is supposed to be a flying pig. I don't see why Antiriad shouldn't count. Stepping into the suit doesn't seem to me as any different to changing outfit in Exolon or The Great Escape . then it's the same as entering a tank in ik...
by Lethargeek
Wed Dec 06, 2023 2:40 pm
Forum: Games/Software
Topic: Games where the main sprite changes
Replies: 37
Views: 1183

Re: Games where the main sprite changes

Transformers, Draconus

don't think Antiriad counts - otherwise we must include Ikari Warriors :)
by Lethargeek
Fri Dec 01, 2023 4:01 pm
Forum: Emulators
Topic: New discovery on Z80 I/O block instructions
Replies: 15
Views: 1731

Re: New discovery on Z80 I/O block instructions

yep... I was there when Patrik was working on the new releases of his test suite. We knew about new discoveries about the CCF/SCF instructions and the flags of block instructions, which motivated the update. We didn't check all the tapes of the new version on real hardware, sorry. owww... trust no ...
by Lethargeek
Fri Dec 01, 2023 3:50 pm
Forum: Emulators
Topic: New discovery on Z80 I/O block instructions
Replies: 15
Views: 1731

Re: New discovery on Z80 I/O block instructions

Actually, I don't know of anyone who specifically tried z80memptr.tap on a real Zilog or NEC until yesterday on Sinclair hardware. i dont remember old discussions details now, but do you mean even Patrik himself never tried it on a real hw :? People usually try z80full.tap and z80ccf.tap. I have a ...
by Lethargeek
Fri Dec 01, 2023 1:55 pm
Forum: Emulators
Topic: New discovery on Z80 I/O block instructions
Replies: 15
Views: 1731

Re: New discovery on Z80 I/O block instructions

TheMartian wrote: Fri Dec 01, 2023 1:05 pm Does this happen in all Z80 models, or just NEC? I'm curious.
couldn't be all, not every one failed Patrik's test before afair, otherwise too many people would complain
by Lethargeek
Thu Nov 30, 2023 1:09 am
Forum: Emulators
Topic: ZX ULAX emulator
Replies: 252
Views: 73054

Re: ZX ULAX emulator

a quick one for the recent Forest Escape this is for the full version, not the demo ; scr2sbuf 109221 0111 0 0111 0 0111 109230 109221 -1928F ; masked 1092E3 C807 1092E8 2160 0131 0536 0337 0113 1092EF 1092E8 -192FB 109300 1092E8 -193A3 1093AD C888 (i won't put it in the game pack while the game is ...
by Lethargeek
Mon Nov 20, 2023 9:21 am
Forum: Design/Ideas
Topic: Stunt car racer for super cpu
Replies: 16
Views: 1011

Re: Stunt car racer for super cpu

Commodore's SuperCpu is 65816 clocked up to 20MHz i.e. you will get clock x20, 16bit accumulator instead of 8bit and 24bit addresss space. Not like all this is needed to speed up old game. On other side, we have Z80 at 7 or 14 MHz (I'm not sure if 28MHz is a thing, last time I was interested in sup...
by Lethargeek
Mon Nov 06, 2023 7:48 pm
Forum: Games/Software
Topic: Which games use teleporting ?
Replies: 103
Views: 3179

Re: Which games use teleporting ?

What do you mean by teleporting in Total Eclipse? Game looks like 3D with flipscreen when you enter rooms. 13:44 a rectangle on the wall (but not used throughout this vid it seems) https://www.youtube.com/watch?v=9_U0V10NlBY&t=824s there are other moments where the exit point is out of place bu...
by Lethargeek
Mon Nov 06, 2023 1:22 pm
Forum: Games/Software
Topic: Which games use teleporting ?
Replies: 103
Views: 3179

Re: Which games use teleporting ?

Antiriad, Total Eclipse (& maybe other freescape games)
by Lethargeek
Sat Oct 28, 2023 1:55 am
Forum: Emulators
Topic: Flashload problems
Replies: 9
Views: 393

Re: Flashload problems

What are the main reasons a program will not load with 'instant' load (e.g. Flashload), when it does load with the speeded up versions (e.g. edgeloader in ZX-Spin). even more intriguing is why in rare cases flashload works but edgeloader fails :? happened to me a few times, can't recall which files...