The MISHAP Tile Scaling Algorithm

jargon · Post by **jargon** » Mon Sep 22, 2008 2:02 am

The MISHAP Tile Scaling Algorithm

progress thus far:

Bregalad · Post by **Bregalad** » Mon Sep 22, 2008 2:09 am

This could be usefull to port NES graphics to C64, where the resolution halves horizontally when using multi-color mode.

jargon · Post by **jargon** » Mon Sep 22, 2008 2:18 am

Bregalad wrote:This could be usefull to port NES graphics to C64, where the resolution halves horizontally when using multi-color mode.

MISHAP is indeed a dual Commodore 64 / Nintendo Entertainment System release that I am developing.

Post by **tepples** » Mon Sep 22, 2008 6:03 am

Bregalad wrote:This could be usefull to port NES graphics to C64, where the resolution halves horizontally when using multi-color mode.

Or CGA, Apple II hi-res, or any other video system that uses "artifact colors" of exactly half the width of an NTSC color cycle. (NES pixels are 2/3 of a cycle wide.)

jargon · Post by **jargon** » Tue Sep 23, 2008 11:17 pm

tepples wrote:
Bregalad wrote:This could be usefull to port NES graphics to C64, where the resolution halves horizontally when using multi-color mode.
Or CGA, Apple II hi-res, or any other video system that uses "artifact colors" of exactly half the width of an NTSC color cycle. (NES pixels are 2/3 of a cycle wide.)

i plan on working out the kinks on half by half, for best clarity, then when i am done with that i will work out how to do arbitary down-scaling.

for airbrushed up-scaling, that is an entirely different algorithm i have irregularly been working on called 'Damascus'. I first started doing major work on the Damascus Filter back when i used to have CVS access for zSNES before it went GPL.

only two four major issues with Damascus, currently, it can only scale up multiples of 100% per axis, it requires 64bit floating point operations, it eats a lot of cpu, and it doesn't have the HSV correction yet that it requires.

Disregarding the lack of HSV correction, it airbrushes all the way to 800x zoom (80000%) and beyond with no other flaws.

however it should be noted that Damascus does not work well for less than 6bpp (bit-per-plane) RGB.

if i had some pictures of what the result of a Damascus airbrush looks like i'd share them, but currently i am having issues with VESA support. :/