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Fast PLOT routine

Posted: Thu Jan 04, 2018 8:34 pm
by Shaun_B
Hi,

Is there any way to PLOT to the screen quickly with a nice bit of assembly? Or is this simply not possible on the ZX81?

Regards,

Shaun

Re: Fast PLOT routine

Posted: Thu Jan 04, 2018 11:39 pm
by PokeMon
You might use HRG-ms from Matthias Swatosch.
This supports full HRG and a nice driver bib with functions to plot and unplug and more.
Easy to use and compatible with ZXmore as well.

http://www.swatosch.de/zx81/

Re: Fast PLOT routine

Posted: Fri Jan 05, 2018 3:14 pm
by dr beep
Define PLOT.

Zx81 pixels (4x4) or 1x1 hires.

It is possible to use scanning for parameters.
Assume fullscreen or not. Fullscreen is faster

Re: Fast PLOT routine

Posted: Fri Jan 05, 2018 3:20 pm
by Shaun_B
Hi Dr Beep,

I was thinking of ZX81 pixels only for now, not high resolution.

Regards,

Shaun

Re: Fast PLOT routine

Posted: Fri Jan 05, 2018 7:37 pm
by XavSnap
Hi,

Yes, Shaun_B ... the internal "PLOT" routine in the ROM is :mrgreen: ...

It slow down all ASM code how using this ROM routine.
:x


Big letters:
http://www.hebdogiciel.free.fr/hd-roms/ ... uslong.zip
http://zx81.ordi5.free.fr/programmes/Big%20Letters.zip

...???
Is there a code to fill a part of the screen? (never seen kind of routine!)

Re: Fast PLOT routine

Posted: Fri Jan 05, 2018 10:29 pm
by Shaun_B
Hi,

I just want some examples of somehow doing fast PLOTing to the screen so I can mess about. Fill, point-to-point and other drawing primitives will come later on if I get that far. Just for fun.

Thanks,

Shaun.

Re: Fast PLOT routine

Posted: Fri Jan 05, 2018 10:42 pm
by GCHarder
Did you see my "Rapid Plot" post in the BASIC forum?

http://sinclairzxworld.com/viewtopic.ph ... lot#p15004

It might give you some ideas.

Regards;

Greg

Re: Fast PLOT routine

Posted: Sun Jan 07, 2018 3:31 pm
by bobs
I could write a lot on this subject, as many of my ZX81 games - especially ZXagon - need to do this. I’m pretty sure I could write a faster routine than the one mentioned here, but the real trick is to not do it from BASIC, so you can use a custom back buffer format which suits the kind of graphics you need to display.