Neat that they did it without a graphics API
(and to be more specific I really meant without opengl|directx|vulcan etc)
mov ax, 13h
int 10h void putpixel_13h(int x, int y, int color)
{
_farpokeb(_dos_ds, 0xA0000+y*320+x, color);
}Modern graphics cards on the other hand can easily push a few million triangles every frame with decent framerates. At 10k triangles * 10 or 20 maps you could load all maps from the game simultaneously and still easily get decent fps.