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base:smooth_linecrunch [2017-03-30 12:04] – karmicbase:smooth_linecrunch [2017-12-13 11:36] (current) – shrydar
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 ====== Smooth Linecrunching ====== ====== Smooth Linecrunching ======
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 +<sub>(note: this article has a slight bug in that each crunched line scrolls the rest of the screen up by 7 pixels, not 8, so the example code actually scrolls the screen up by 7/8ths of the value read out of the sine table. Still works well enough for demonstration purposes, but something to keep in mind if you want to use it as the starting point for an AGSP routine or anything else that requires precise positioning).</sub>
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 Basically linecrunching is a VIC-trick that allows you to easily move graphics vertically on the screen. It is especially useful for bitmaps, where it would take far too much time to move it by copying. Basically linecrunching is a VIC-trick that allows you to easily move graphics vertically on the screen. It is especially useful for bitmaps, where it would take far too much time to move it by copying.
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 Finally, here is the code. 64tass syntax. Finally, here is the code. 64tass syntax.
-<code>sin_index               = $fb+<code 6502tasm>sin_index               = $fb
 char_lines_to_crunch    = $fc char_lines_to_crunch    = $fc
 initial_yscroll         = $fd initial_yscroll         = $fd
base/smooth_linecrunch.txt · Last modified: 2017-12-13 11:36 by shrydar