Let’s Code MS DOS 0x1D: Melting the VGA Screen

One of the effects that is easy to do on machines like the C64 or Amiga is the „melting screen“. In theory you can do such things just by copying lots of pixels in video memory. However the VGA is rather slow for doing that. So what we will do instead is cleverly manipulating the CRTC registers of the VGA to achieve a similar effect. This lets us move big portions of the screen without actually copying any bytes.