Controlling sprites with the joystick on the C128

[Frozone212]

I RTFM and no luck. Any ideas?

[DavidC]

https://www.commodore.ca/manuals/128_system_guide/sect-06b.htm

[DavidC]

 

[Casey]

I'm not near a 128, but a combination of the JOY function and MOVSPR command should do what you want.

 

JOY(1) returns the position of joystick port 1 such that starting at Up/North as 1, the directions are numbered clockwise from 1-8 (so 8 is NW).  The fire button adds 128 to the value returned.

 

Take this value and feed it into MOVSPR - it expects degrees.

 

So, as a quick example:

10 A=JOY(1):IF A>128 THEN A=A-128

15 IF A=0 THEN MOVSPR 1,45*(A-1)#0:GOTO 10

20 MOVSPR 1,45*(A-1)#5

30 GOTO 10

 

This should move an already defined sprite in the direction the joystick is being pushed at speed 5.  It ignores the fire button, but you could put logic in there to check and do something different if the fire button is pressed.  If the joystick is released, the sprite stops moving.  

Edited December 24, 2022 by Casey

[Frozone212]

thank you, this is what I wanted