Slide Show

Slide Show





Stewart Stallworthy,


Rickmansworth,


Hertfordshire.





This routine can be used to Poke to the screen any pre-


defined picture or pictures. Whilst a Basic program would


take approximately 60 seconds, this routine takes less than


one second, and can therefore be usefully incorporated in


Basic programs. First draw a picture on the screen, then


save it on tape -


SAVE "Picture" SCREEN$


The next step is to load the picture bytes into memory.


The routine is written to look for them at memory address


40100.


CLEAR 39997


LOAD "Slide" CODE 40000,48


LOAD "Picture" CODE 40100,6912


Now type


RANDOMIZE USR 40000


and all should be revealed. Each picture takes 6912 bytes,


and additional pictures may be located at other memory


addresses, for example 47013 and 53926. If these are used,


it will be necessary to make the routine look at the


correct starting address, and this is done as follows. For


picture starting at memory address 47013,


POKE 40008,165


POKE 40009,183


For picture starting at memory address 53926,


POKE 40008,166


POKE 40009,210