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AMAL


Instruction only valid in autotest
The Direct or the eXit instructions have been called from the main AMAL program, by mistake.

Illegal instruction in Autotest
Autotest can only be used together with a limited range of AMAL commands. Objects cannot be moved or animated in any way from inside an Autotest, so check for misuse of instructions such as Move, Anim or For ... Next structures.

Jump To/Within Autotest in animation string
The commands inside an Autotest are completely separate from the main AMAL program, and direct jumps are not allowed inside an Autotest procedure. To leave an Autotest and return to the main AMAL program, either Direct or eXit must be used.

Label already defined in animation string
You are trying to define the same label twice in an AMAL program. All AMAL labels consist of a single capital letter (For example, "Test" and "Total" are seen as two versions of the same label "T". This error can also be generated if two instructions have been separated by a colon. Semi- colons should be used for this purpose.

Label not defined in animation string
You are trying to jump to a label that does not currently exist in your animation string.

Next without For in animation string
Every For command must be matched by a corresponding Next statement. Check any nested loops for an unnecessary Next.

Syntax error in animation string
A mistake has been made when typing in an animation string. AMAL commands consist of one or two capital letters only, and not full keywords as used in AMOS Professional Basic.

Compatibility with STOS animation commands
AMOS Professional has evolved from the original STOS Basic, written by François Lionet and released in 1988 for the Atari-ST. STOS included a celebrated and powerful animation system using interrupts, which allowed Sprites to be moved in complex patterns. Although this system has been overshadowed by AMAL, it still provides a simple introduction to Amiga animation. Furthermore, the following commands will allow those loyal AMOS Professional users, who created STOS programs in the past, to convert STOS to AMOS!

Unlike STOS, the movement patterns in AMOS Professional can be assigned to any animation channel, and the MOVE commands can be used to animate Bobs, Sprites and screens, using exactly the same techniques.

As a default, all animation channels are assigned to the equivalent hardware Sprites, but because Bobs are much closer to the standard STOS Sprites, it may be found more convenient to substitute Bobs by adding a set of CHANNEL commands at the start of a program, like this:

X> Channel 1 To Bob 1
   Channel 2 To Bob 2
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07.06.21