Routines
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25171: Multiply HL By Four
Used by the routines at OffsetBlipLeft, OffsetBlipDown, LocateRadarBlip and CollisionCup.
Used to convert a distance (in doubled map units) into radar pixels, which are then found in H.
Input
HL Value
Output
HL Value multiplied by 4
MultiplyHLByFour 25171 LD B,2 Set the shift counter to 2.
MultiplyHLByFour_Loop 25173 RL L Rotate HL left by one place.
25175 RL H
25177 DJNZ MultiplyHLByFour_Loop Decrease the shift counter by one and loop back to MultiplyHLByFour_Loop until both shifts have been done.
25179 RET Return.
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