Basically we had this memory limit in DOS. It was pathetic, like 600K. Memory extenders came out that let you reach over that limit. But you had to make OS cal

Basically we had this memory limit in DOS. It was pathetic, like 600K. Memory extenders came out that let you reach over that limit. But you had to make OS calls that flipped the CPU into a different mode first. That was just the beginning! We also had to write 'self modifying code', emit assembly instructions and make DOS programs rewrite themselves to squeeze every last bit out of graphics routines. I remember counting 'cycles' of each ASM instruction. Fixed point was much faster than float then, we did craaaazy things for 3d graphics, for sure. Those were fun days of hobby dev, for sure!