Brute Force Colors
The original Macintosh reserved something like 22K of the RAM for screen memory. I remember reading a little tech note about page-flipping: where you can pull in another 22K of RAM for a secondary screen buffer, write to it, and then with a single assignment to a 32-bit memory location, point the screen refresh to your secondary screen buffer. If you did it during the vertical screen blanking interval, pop!, instant "page flip".<p>I was playing around with 68K assembler to test this out: cleared one screen buffer to white, drew a diagonal black line — cleared the other screen buffer to white and also drew a diagonal black line ... a mirror of the first one though.<p>Watching it page flip between the two screen buffers for every screen refresh caused me to notice something interesting: you could actually get a pseudo 50% gray where a black pixel and white pixel shared the same row and column on the two buffers.<p>It might have made an interesting demo, but eating another 22K on a computer that was struggling (not the lower config models) with 128K seemed like a bad design decision. I suspect too, at 30 FPS, the gray would have been a bit "strobish"?