1k hires idea, adaptation of Grandpr1x
1k hires idea, adaptation of Grandpr1x
The idea is to race a set time. Largest distant as record. Speed loss on collision with corners.
View as if you are on a motor, so the road will move as you steer left or right or miss a turn without steering.
This is possible with a simplified view of the road.
Since the ZX81 has no DRAW-command this must be written, but that is possible with a simplified routine.
Not the difficult/large routine from the spectrum is needed.
The calculation of the lines is already working. Now the PLOTTING of the pixels must be added.
The hiresroutine is calculated and shoul work.
Screen will be smaller than this version.
Re: 1k hires idea, adaptation of Grandpr1x
Screenroutine is working.
Had some trouble getting lowres and hires together, but the cause was setting an initial screen, not the routine.
Now I need to work on the plotting of the course.
Thinking of extending the track, but only when memory will allow it.
Had some trouble getting lowres and hires together, but the cause was setting an initial screen, not the routine.
Now I need to work on the plotting of the course.
Thinking of extending the track, but only when memory will allow it.
Re: 1k hires idea, adaptation of Grandpr1x
Always amazed what you are able to get out the humble 1k zx81. Also enjoy reading your updates on seeing your screenshots on the forum.
Memotech rules
Re: 1k hires idea, adaptation of Grandpr1x
I have made a plotroutine in excel to test a thought.
This is working, but now it needs to be translated to Z80-code.
Hardest part: determine the pixelposition in a 16 bit moving displayline.
As I write this I have an idea.
This is working, but now it needs to be translated to Z80-code.
Hardest part: determine the pixelposition in a 16 bit moving displayline.
As I write this I have an idea.
Re: 1k hires idea, adaptation of Grandpr1x
Working on the plottingroutine.
For easy display first routine on the ZX Spectrum.
In this way the Spectrum can be used with the screen for check.
First real display shows some adjustment on the move left and draw rightline and other way around.
Pro, I am coding in Z80, so when screen is ok only I only need to change writing to ZX into writing to Zeddy.
For easy display first routine on the ZX Spectrum.
In this way the Spectrum can be used with the screen for check.
First real display shows some adjustment on the move left and draw rightline and other way around.
Pro, I am coding in Z80, so when screen is ok only I only need to change writing to ZX into writing to Zeddy.
Re: 1k hires idea, adaptation of Grandpr1x
So the routine is now working on the ZX Spectrum, but on the ZX81 the displayeffect of the previous line must be eliminated, so that is the next step step to alter in the routine. Undo the effect of the previous line. Then display can be ported to the ZX81.
Re: 1k hires idea, adaptation of Grandpr1x
Haha,
Solution to the problems seems way to easy. When I shift the display of the line it seems to clear the previous position always.
Solution is to add 4 instead of 3 to a calculation.
No costs of bytes in code or datastorage.
Solution to the problems seems way to easy. When I shift the display of the line it seems to clear the previous position always.
Solution is to add 4 instead of 3 to a calculation.
No costs of bytes in code or datastorage.
Re: 1k hires idea, adaptation of Grandpr1x
I have the display now working.
Now I need to make the creation of the tracks a bit similar to GranpPr1X. Not quite the same yet.
Hires screen sofar : 286 bytes.
Program so far : 300 bytes.
Now I need to make the creation of the tracks a bit similar to GranpPr1X. Not quite the same yet.
Hires screen sofar : 286 bytes.
Program so far : 300 bytes.
- GP-vs-RR.png (34.19 KiB) Viewed 4008 times
Re: 1k hires idea, adaptation of Grandpr1x
So the good news is that I have recovered the source of Grandpr1x to figure out how the drawing was done.
The bad news is: it is on an old laptop where the diskettestation refuse to save.
Source now saved by taking pictures of the screen.
The bad news is: it is on an old laptop where the diskettestation refuse to save.
Source now saved by taking pictures of the screen.
Re: 1k hires idea, adaptation of Grandpr1x
I remember the technic used to create the track. Now I must alter it in 1K for the ZX81.