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# Dithered rendering

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Today I continued venture in high resolution bitmap mode of C64's VIC-II. As I mentioned yesterday, I started adding colors. First attempt looked butchered, but that was obvious for me when I started working on it. I used iteration depth as color for pixels in the 8x8 char area, and it gave me these blocky results:

I decided to use dithering. Since I have 16 levels of depth ( not counting the escaping shape ), each 4 levels would have their own dither level. It was a matter of finding some free memory, and poking it with tons of chars that would represent the dithering mask. My goal was to create something like

so I opened up my binary calculator and found the following values:

poke 16192,0poke 16193,34poke 16194,0poke 16195,0poke 16196,0poke 16197,34poke 16198,0poke 16199,0poke 16200,0rem end char onepoke 16201,170poke 16202,0poke 16203,170poke 16204,0poke 16205,170poke 16206,0poke 16207,170poke 16208,0rem end char twopoke 16209,85poke 16210,170poke 16211,85poke 16212,170poke 16213,85poke 16214,170poke 16215,85poke 16216,170rem end char threepoke 16217,255poke 16218,255poke 16219,255poke 16220,255poke 16221,255poke 16222,255poke 16223,255poke 16224,255rem end char four

The free memory I used ( 16192-16224 ) was placed immediatly after my screen memory space. I've played around a bit with the code and ended with this result:

It may not be perfect ( colors are still blocky ), but it's SOMETHING. Maybe later today I'll add color+background dithering for smoother color transitions.

See you later then!

## 1 Comment

That's quite an impressive difference.

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