Search found 52 matches

by RobertK
Tue Feb 06, 2018 8:37 am
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Re: Plot function in z88dk

Thanks once more, the parameterised function works great as well. just thinking about this... probably already functions out there but a Bresenham line and circle function would go nice with this. And maybe more important: a function that checks whether there is a plotted pixel at (x,y), we could ca...
by RobertK
Thu Feb 01, 2018 11:31 pm
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Re: Plot function in z88dk

Thanks Andy, that works just GREAT!

I hope that I will soon be able to post a little program that uses these functions.

And I hope some z88dk expert can try to merge the two functions, I assume that two functions need more memory than just one...
by RobertK
Thu Feb 01, 2018 10:56 am
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Re: Plot function in z88dk

Here is my sample program using a function I found at the z88dk forums, but for some reason my plotted dots don't appear: // found at https://www.z88dk.org/forum/viewtopic.php?id=6271 // Contributors: swensont, siggi, Timmy, alvin #include <stdio.h> #include <zx81.h> // alvin: "It's faster to pop th...
by RobertK
Wed Jan 31, 2018 3:53 pm
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Re: Plot function in Z88DK

Thanks Andy, the speed is impressive! I may seem entirely hopeless, but can anyone please assist me in wrapping this ASM code into a C function? I know that you need to put the ASM code between #asm and #endasm, but everything else regarding ASM in z88dk is currently trial and error for me. I should...
by RobertK
Tue Jan 30, 2018 10:09 am
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Re: Plot function in Z88DK

Thanks, I will try writing WRX programs later, but back to my initial question: the target machine for my first program would be an unmodified 16K ZX81/TS1000, and I would like to plot/unplot blocks in low-res 64x48 mode. Any suggestions how this could be achieved efficiently in Z88DK? I had a look ...
by RobertK
Mon Jan 29, 2018 10:39 pm
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Re: Plot function in Z88DK

Thanks. I have tried the first method and it works, but unfortunately its speed is exactly the same as if it was done entirely in BASIC. About six seconds for plotting a border around the screen like this: 10 FOR X=0 TO 63 20 PLOT X,43 30 PLOT X,0 40 NEXT X 50 FOR Y=1 TO 42 60 PLOT 0,Y 70 PLOT 63,Y ...
by RobertK
Mon Jan 29, 2018 4:37 pm
Forum: Development
Topic: Plot function in z88dk
Replies: 35
Views: 25663

Plot function in z88dk

Sorry for this beginner’s question, but how would you implement a Plot() function in z88dk , allowing you to set or clear each block of the 64x48 screen? The trick is obviously to fill the right parts of the screen memory. I have made my first little experiments with Z88DK, and the speed of the resu...
by RobertK
Sat Jan 13, 2018 8:35 pm
Forum: Hardware
Topic: Chroma 81 - SCART and Colour interface for the ZX81
Replies: 158
Views: 98533

Re: Chroma 81 - SCART and Colour interface for the ZX81

However, a more robust solution is to simply reverse the order in which the game checks for the keys, i.e. if it does not detect keys 5 or 8 being pressed then it goes on to check for the SHIFT and Z keys. The attached version uses this approach. This version is perfect, thanks! Attached is the .co...
by RobertK
Fri Jan 12, 2018 9:06 pm
Forum: Hardware
Topic: Chroma 81 - SCART and Colour interface for the ZX81
Replies: 158
Views: 98533

Re: Chroma 81 - SCART and Colour interface for the ZX81

Ok, then I think we can call this finished and you may publish it on your web site if you want, together with your patched game file. Attached is a new patched version of the game that supports both the standard control keys and the cursor control keys. spaceraiders(standard_and_cursor_keys).zip Wow...
by RobertK
Fri Jan 12, 2018 1:46 pm
Forum: Hardware
Topic: Chroma 81 - SCART and Colour interface for the ZX81
Replies: 158
Views: 98533

Re: Chroma 81 - SCART and Colour interface for the ZX81

Have you tried making the blue and green characters forming the aliens the same colour, which would give their colouring full symmetry? We could of course make both "eyes" the same colour, but then we would have one colour less displayed on the screen. I thought that it won't look too disturbing in...