Using HALT under WRX Hires...

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Spinnetti
Posts: 253
Joined: Sat Sep 12, 2020 11:29 pm

Using HALT under WRX Hires...

Post by Spinnetti »

Hi,

Probably a dumb question, but writing a game for the zeddy in ML and WRX. I have everything moving along nicely, but when my character prints, its kind of "flashy". Because there is an idle pose animation, I clear the sprite then print frame 1, then clear, print frame 2 etc. I get the idea in general of either doing the calcs before the display starts or "chasing the beam", but not quite sure how to do that. Specifically, I understand HALT waits for a VBI? - but does that even work in WRX? I tried to sprinkle in some right before I clear and reprint my "sprites" but it doesn't seem to do anything. Is there anything out there on getting solid looking graphics with WRX?

Thanks!
Zeddy: ZX80, ZX81/ZXpand, TS1000/ZXpand, TS1500/Zxpand+
Speccy: 48k, +, +2, +3, TS2068, "Bare Metal" Pi, Next KS2, IF1/Microdrives/Vdrive/Light Gun/VGA-Joy
QL: Minerva/QL-VGA/Custom PSU
C5: 24v, LiFE battery, Disc brakes
dr beep
Posts: 2060
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Using HALT under WRX Hires...

Post by dr beep »

when you alter data on the screen while doing display remember that the time you alter code you won't do display. It is possible, but you will have a smaller screen or blanc lines between characters.

Multiple of my 1K hires games alter or read data while doing display.
dr beep
Posts: 2060
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Using HALT under WRX Hires...

Post by dr beep »

When the frames overlap you could also NOT clear but write second immediately.
Would you share your game so I can take a look?
Spinnetti
Posts: 253
Joined: Sat Sep 12, 2020 11:29 pm

Re: Using HALT under WRX Hires...

Post by Spinnetti »

Ah, I see, I'll have to think more deeply on that - I guess the frames mostly overlap so that would work most but not all the time. I'm almost ashamed to share code because I'm not very good at it lol... Can I email it to you?

- Key things I'm struggling with using full screen WRX (no 1K challenge here!)
-Writing to the screen without flashing
-Sprite overlap that isn't ugly. I tried clearing all my sprites first then writing the sprites and the overlap problem is cured but its too flashy
Last edited by Spinnetti on Thu Mar 23, 2023 6:00 pm, edited 1 time in total.
Zeddy: ZX80, ZX81/ZXpand, TS1000/ZXpand, TS1500/Zxpand+
Speccy: 48k, +, +2, +3, TS2068, "Bare Metal" Pi, Next KS2, IF1/Microdrives/Vdrive/Light Gun/VGA-Joy
QL: Minerva/QL-VGA/Custom PSU
C5: 24v, LiFE battery, Disc brakes
dr beep
Posts: 2060
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Using HALT under WRX Hires...

Post by dr beep »

Spinnetti wrote: Thu Mar 23, 2023 4:33 pm Ah, I see, however I'm clearing the old position then writing the new, so a straight up overwrite doesn't quite work. I'm almost ashamed to share code because I'm not very good at it lol... Can I email it to you?
See PM for email
dr beep
Posts: 2060
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Using HALT under WRX Hires...

Post by dr beep »

I have an idea how to check when a display will occur without delaying display. I will try this out later....
dr beep
Posts: 2060
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Using HALT under WRX Hires...

Post by dr beep »

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