Tales of the Rampant Coyote

Adventures in Indie Gaming!

How “Old School” Graphics Worked

Posted by Rampant Coyote on August 26, 2015

Oh, man. This brings up some memories. I worked with the Commodore 64 graphics for years. Never produced anything commercial, but I certainly struggled with these challenges.

There’s something he doesn’t bring up in the video about the Commodore 64’s sprite mode. Each sprite had its position dictated by two bytes – one for X position, one for Y position. Now, if you are a programmer, you can recognize that there’s a problem with 320 x 200 resolution… there’s more horizontal screenspace than can be represented by a single byte. So there was another value you’d have to tweak to set the “seam” bit which acted as an extra bit of information that set the value to 256+the X value. Basically it expanded the horizontal resolution to 512 instead of 256. It was kind of a pain in the butt to work with, especially in BASIC.

There’s a reason why old-school games were so driven by tech and programming. It took a lot of fancy code to get those graphics to work, and at speed.

Filed Under: Art, Programming, Retro - Comments: 3 Comments to Read