First Commit

Upload literally everything from the pokecrystal16 expand-move-ID branch

engine/math/get_square_root.asm

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+DEF NUM_SQUARE_ROOTS EQU 255
+
+GetSquareRoot:
+; 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:
+for x, 1, NUM_SQUARE_ROOTS + 1
+	dw x**2
+endr