Routines
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B6F8: Set Position In Cell
Used by the routines at CreateTumbleweed, CreateDirectionPointer and CreateBystander.
Sets where an object stands within its cell, from the position of the sheriff within his cell. The routine uses C as left by GetMapCell, and PlaceNearSheriff must have been called first.
Input
IY The address of the object
Set the horizontal position within the cell.
SetPositionInCell B6F8 LD A,($A27E) Fetch the horizontal position of the sheriff within his cell.
B6FB AND %11000000 Keep the top two bits.
B6FD OR %01000000 Set bit 6.
B6FF BIT 0,C Jump to SetPositionInCell_Horizontal if bit 0 of C is clear.
B701 JR Z,SetPositionInCell_Horizontal
B703 NEG Negate the position.
SetPositionInCell_Horizontal B705 LD (IY+$01),A Set the horizontal position of the object within its cell.
Set the vertical position within the cell.
B708 LD A,($A280) Fetch the vertical position of the sheriff within his cell.
B70B AND %11000000 Keep the top two bits.
B70D OR %01000000 Set bit 6.
B70F BIT 1,C Jump to SetPositionInCell_Vertical if bit 1 of C is clear.
B711 JR Z,SetPositionInCell_Vertical
B713 NEG Negate the position.
SetPositionInCell_Vertical B715 LD (IY+$03),A Set the vertical position of the object within its cell.
B718 RET Return.
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