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Was thinking of doing some scroll routines. I see there are some useful ones in scroll.bas in the library.
However, there appears to be a left, right and another left in there - no up and down!
sub fastcall ScrollRight
sub fastcall ScrollLeft
sub fastcall ScrollLeft
two also begin a bit strangely - loading the byte at (screenaddress) twice?
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*bump*
Are these okay? Do we need replacements?
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I have never used scroll, so dunno how they act under gaming conditions
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Window scroll up is already in wiki library. Scroll down would be a trivial alteration from that.
Left and right is a matter of using 9 bit rotates to carry to next byte - for a single pixel. More than one pixel is a bit tougher to do.
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I recall there's already a SC/ROLL (Roll means exiting pixels reenter the opposite side) in a MicroHobby machine listing.
I think I could rip them from there.
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what do the four numbers represent?
Cant figure it out!!
Whenever I make changes to the numbers the results make no sense
If I change the first 2 numbers to zero the same scroll happens at 40,40
then other numbers when increased make the window smaller!
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You mean <!-- m --><a class="postlink" href="http://www.boriel.com/wiki/en/index.php/ZX_BASIC:WindowScrollUp">http://www.boriel.com/wiki/en/index.php ... owScrollUp</a><!-- m --> ?
Unless it broke somewhere, and I remember correctly (it's been years); X and Y should be the top left corner, and the other two numbers are the width and height of the window.
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It's in the demo folder of the latest release
The demo prints a bunch of letters to the screen, then they are scrolled in all directions
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The numbers dont seem to behave as I would expect, can someone take a look?