horizontal scrolling in basic

Shaun_B
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Re: horizontal scrolling in basic

Post by Shaun_B »

What's happening with the 23606 poke?

Thanks,

Shaun
dr beep
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Re: horizontal scrolling in basic

Post by dr beep »

Since we are talking POKING 23606 and own development of characterset and Shaun Bebbington replying....


Define your own "characterset" (this can be UDG too, but in characterrange) and make it 10 characters/udg. Make the 11th the same as the first.

Now by poking 23606 from start to start+80 and printing a character on same spot after each poke you get the rolling effect
from a fruitmachine. Since chr11 is the same as chr1 you will get the rollaround effect.
To add more visible chr on the roll: add print chr-1 above and chr+1 below.
Shaun_B
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Re: horizontal scrolling in basic

Post by Shaun_B »

Thanks Dr Beep - I've actually thought of a way to improve my advanced** fruit machine simulator for 1K ;-)





** Might not be so advanced
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1024MAK
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Re: horizontal scrolling in basic

Post by 1024MAK »

Shaun_B wrote: Mon Aug 14, 2017 8:12 pm What's happening with the 23606 poke?
By increasing the value by 8, you move the start point of the look up to the pattern data so that BASIC prints the image for the next character pattern to the screen. So for the first increase, when 'A' is printed, the system uses the pattern for letter 'B' instead.

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Crayon21
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Re: horizontal scrolling in basic

Post by Crayon21 »

that was impressive, to be honest :o
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