1. simulates texture filtering and dithering hiding low resolution and low number of colors in textures, and
2. renders two or four columns at once.
Amiga had planar graphics, which did not support setting individual pixels. To set a pixel you'd have to set appropriate bit in up to 6 bytes (64 colors max) scattered around in memory. Writing one byte modified one bit of 8 adjacent pixels, which was terrible for textured 3D graphics.
1. simulates texture filtering and dithering hiding low resolution and low number of colors in textures, and
2. renders two or four columns at once.
Amiga had planar graphics, which did not support setting individual pixels. To set a pixel you'd have to set appropriate bit in up to 6 bytes (64 colors max) scattered around in memory. Writing one byte modified one bit of 8 adjacent pixels, which was terrible for textured 3D graphics.