I recently bought a copy of GFA BASIC V3.5 for the Amiga, which was a manual and one floppy disk. The date on the manual is 1990, but it says it was first printed then, so this may be a reprint. A section at the back lists all the new commands for version 3.5 instead of incorporating them into the main part of the manual. I had never used GFA BASIC before this year, probably because it first appeared on the Atari ST. I used AmigaBASIC and AMOS. I probably assumed that any programs written in GFA BASIC would look like ST programs, but I was wrong. I enjoyed the example programs, which include HAM graphics and sprites. Any programs I've seen so far written in this language look like Amiga programs with Intuition style windows and screens and can be multitasking, unlike the Atari ST. Unfortunately, AMOS bypasses the Amiga Workbench. This may be OK for games, but any other programs written in it don't look like Amiga programs.
I feel I'm really making progress with GFA BASIC, although I've never got that far with C or 68K Assembler!
Unfortunately, although the manual is quite thick it doesn't go into all that much detail for each command. There are over 300 commands! I've been looking for more documentation, but haven't found much. I'm watching some books about it on eBay Germany in German, which I speak. I've found some books on eBay UK about the Atari ST version, which I hear is almost identical, apart from GEM specific commands. GFA BASIC now seems to be abandonware, but has an unofficial home site and is still maintained with a version for Windows 7! I've also read that X11 BASIC for Linux is very similar to GFA BASIC.
Some annoying features are that the example program called pogosprites, featuring hot air balloons, usually refuses to run, bringing up the error that it's too long. This is on an Amiga A500 Plus with 3Mb RAM. I'm not sure how I've managed to run it a few times. I'm also getting tired of the editor colours of black text on a grey background. I'd really like to change this, but there doesn't seem to be any option to do this. Perhaps someone has got a program which would change the registers or RAM locations that set these colours. I also wonder if it's possible to somehow use AGA graphics. The manual says it's possible to use the library functions, which it lists, but doesn't go into much detail about how to do this.
Can anyone tell me where I can find some more documentation, apart from the sources mentioned above?