What is zx pixel

Post Reply
Sinclairs-great
Posts: 36
Joined: Wed Nov 06, 2019 1:37 am

What is zx pixel

Post by Sinclairs-great »

What exactley is,

Spectrum BASIC keyword to put a pixel on the screen
User avatar
1024MAK
Posts: 5118
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: What is zx pixel

Post by 1024MAK »

PLOT is used to draw a single pixel. In simple terms PLOT x coordinate, y coordinate

PLOT c;x,y
Prints an ink spot (subject to OVER and INVERSE) at the pixel x,y; moves the PLOT position.
Unless the colour items c specify otherwise, the ink colour at the character position containing the pixel is changed to the current permanent ink colour, and the other (paper colour, flashing and brightness) are left unchanged.
x should be between 0 and 255, y should be between 0 and 175, else error B

DRAW is used to draw a line.

DRAW x,y

or

DRAW x,y,z

Draws a line from the current plot position moving x horizontally and y vertically relative to it while turning through an angle z.
Error B if it runs off the screen

Also

CIRCLE x, y, z

Draws an arc of a circle, centre (x,y), radius z

I hope this helps.

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
Post Reply