X and Y

[Crayon21]

is there an equivalent command for the zx81?

[XavSnap]

… On the Zx81 Basic ?
No…

With a UDG card, just redefine the right characters to display.

[Crayon21]

UDG card? Like an SD? I'm using an emulator not the physical hardware, and even if i could, they're almost $600

anyway, what do i do? what command?

[1024MAK]

UDG card is an extra PCB that connects to the ZX81. The most common from the time of the ZX81 had various “UDG” in ROM. But the same PCB could have a RAM chip, and then you could design your own UDG. One limitation was that either the extra ROM or the extra RAM based UDG characters completely replaced the standard ROM character set.

The original UDG boards had to be fitted internally to a ZX81. However, the modern designs fit externally.

Mark

[Crayon21]

I'm trying to create a pong clone for the zx81. how do i get the graphics to move (I.E Like in 3D monster maze except this is 2D)
? I want to map the up and down keys to W and S or Up and Down respectively. any help would be appreciated. trying to fit in 2k

[dr beep]

Make the bats with a leading and ending blanc, then you don’t need to erase the bat on movement.
For speed use PRINT AT, also for ball but calculate which graphic is needed (4 possible).
You need to erase the ball before reprinting because it can move to another position.
Do not print ball on the bats but test before it is there and only print it when no bat is there to show a miss.

[dr beep]

I'm trying to create a pong clone for the zx81. how do i get the graphics to move (I.E Like in 3D monster maze except this is 2D)
? I want to map the up and down keys to W and S or Up and Down respectively. any help would be appreciated. trying to fit in 2k

2K must fit. I did it in 1K and hires.
https://m.youtube.com/watch?v=lbgyXvxuf6U

[dr beep]

UDG card is an extra PCB that connects to the ZX81. The most common from the time of the ZX81 had various “UDG” in ROM. But the same PCB could have a RAM chip, and then you could design your own UDG. One limitation was that either the extra ROM or the extra RAM based UDG characters completely replaced the standard ROM character set.

The original UDG boards had to be fitted internally to a ZX81. However, the modern designs fit externally.

Mark

USCII is a tool which allowes you to use UDG in BASIC without special hardware, only a RAM-pack capable of hires.
viewtopic.php?f=6&t=3124&p=33382&hilit=Uscii#p33382

[Crayon21]

On Amstrad Basic, there is the TAGON/TAGOFF command to set a character location on the X/Y matrix.
But, Sinclair took the Zx81 basic to build the Spectrum… not the CPC.
You can't do that, you never be able to do this…
Harrrg….

The only way to move a character from X to X+1 or Y to Y+1 is to redefine a 8 bits bloc on 2 characters.


But, it's not easy.

udg.JPG

been meaning to ask you about the tool, it requires java. any workaround?

[XavSnap]

On the VB81 XuR, you can directly draw on the screen.
Move the cursor on screen, and note all coordonates on Y or X... [EasyDraw in the tools menu]