ref: 4c4fca1028c2d0906dc101d89ca6e0be4664c342
dir: /engine/routines/getsquareroot.asm/
NUM_SQUARE_ROOTS EQU 255 GetSquareRoot: ; 13b87 ; Return the square root of de in b. ; Rather than calculating the result, we take the index of the ; first value in a table of squares that isn't lower than de. ld hl, .Squares ld b, 0 .loop ; Make sure we don't go past the end of the table. inc b ld a, b cp NUM_SQUARE_ROOTS ret z ; Iterate over the table until b**2 >= de. ld a, [hli] sub e ld a, [hli] sbc d jr c, .loop ret .Squares: ; 13b98 x = 1 rept NUM_SQUARE_ROOTS dw x * x x = x + 1 endr