porting MojonTwins games to QL - how difficult it is?

[nitrofurano]

hi!
I imagine most of you actually know games from Mojon Twins
How difficult would be porting them to QL? (about 68k architecture, some were actually ported to Sega-Megadrive - but of course, the video hardware on QL is far more limited (no hardware sprites, halftone colours only obtained by halftone patterns (specially on the pristine QL machines) (like those at http://foro.speccy.org/viewtopic.php?f= ... 9&start=15 ) ), and situations like this can be counted with)
I'm really curious about comments on this topic!

[vanpeebles]

I've no idea myself but I'd love to see more games of any kind on the QL

[radastan]

And here I come...

Ok, I worked in three games with Mojon twins engine for three games in ZX Spectrum. The engine is called "churrera", and is based on C languaje with SPLIB2 + Z88DK. Is possible to make a port of the engine to QL, but I need a C cross compiler on PC for make it possible.

The engine use:
- screens in binary format
- map in mappy format (converted with a translator to the engine needs)
- a placer for enemies, that runs on Windows
- Graphics tiles and ASCII font in a special disposal
- Sprites in a special disposal

The work of make a port of the engine to QL would we astouning, is better to make a new one and special utilities for QL (image converter, map disposal, etc).

I only needs a C cross compiler, I have sprite ASM routines for QL yet, and tons of graphics prepared for make games.

Examples (deformed, are on 256x256 with no aspect ratio correction):

[RWAP]

There is an Amiga port of the Z88DK - I wonder whether this could be used as a starting point - I can only find a v1.5 version for the Amiga though - maybe I am not looking in the right place....

[thorsinclair]

Funny, I also did a Donkey Kong graphics conversion 2 years ago.

donkey kong.gif (3.78 KiB) Viewed 7015 times

and this:

ST Karate.png (7.46 KiB) Viewed 7015 times

[radastan]

How wasted is the QL for games...

[vanpeebles]

Very! Sadly QL games never had the history of development that the Speccy did so very few games actually push the system to its full potential.

Fleet Tactical Command stands out for me as one that really shows what the QL could do.

[nitrofurano]

after all these years, are there more news about porting these games, and La Churrera engine as well? i'm indeed curious...

[bwinkel67]

There's currently a lot of activity of creating ports for the new game Attack of the Petscii Robots. Most are for 6502 in assembly though there is an Amiga port in C with some assembly. Not sure if the source code is public. But would be nice to get in on the ports being made for that game as new machines keep popping up. I guess there is a sort of port since you could run the ZX Spectrum emulator which has a version running.

[Derek_Stewart]

Hi,

Most 8 bit CPUs could be emulsted by the 68000 by using the QMAC Macro assemblers macro facilites to generate 68000 code from Z80 or 6502 op codes, I started this project many years ago and never really completed it.

There would be alot of hardware specific code to change for the QL. But comparing the QL with 8 colours 256x256 pixels or 4 Colours 512x256 pixels to say a ZX Spectrum 8 colours, 256x192 pixels, the QL has the same colour range, with more resolution with 8 colours.

So i theory the QL could run most Spectrum games, if a way to convert the Z80assrmbler to 68000 assembler could be found.

I also looked at Z88dk, which looks to be a Small C compiler, which is a subset of ANSI C. The QL has DP Digital C which a Small C compiler and there is C68 nearly ANSI C compliant.

Maybe C68 coould be used to port Z88dk and graphics libraries written.

I am not sure I have the skill, or good looks to perform this, but I will have a look at the Z88dk source code.