Routines
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37187: Find Hit Position
Used by the routines at UpdateEnemies and CheckObjectHitByShot.
Works out the screen position of the object that was hit, and sets up the hit data used by CheckShotCollisions. Does nothing if the collision flag at 41432 is clear.
FindHitPosition 37187 LD IY,(44358) Fetch the address of the object from CurrentObject.
37191 LD L,(IY+17) Fetch its screen position into HL.
37194 LD H,(IY+18)
37197 LD A,(23593) Fetch the value from 23593 into E.
37200 LD E,A
37201 LD A,(41432) Fetch the collision flag from 41432 into D.
37204 LD D,A
37205 LD A,D Copy it into A.
37206 DEC A Subtract one.
37207 RET M Return if it was zero.
37208 LD A,(41722) Fetch the flag from SpriteVariables_RightEdge.
37211 AND A Test it.
37212 LD A,L Fetch the horizontal screen position.
37213 JR Z,FindHitPosition_Clear Jump to FindHitPosition_Clear if the flag is clear.
37215 ADD A,E Add the value from E.
37216 LD L,8 Set the horizontal screen position to 8.
37218 SUB L Subtract it.
37219 LD E,A Keep the result in E.
37220 JR FindHitPosition_Store Jump to FindHitPosition_Store.
FindHitPosition_Clear 37222 ADD A,23 Add 23 to the horizontal screen position.
37224 ADD A,E Add the value from E.
37225 JR NC,FindHitPosition_Store Jump to FindHitPosition_Store if there is no carry.
37227 LD A,238 Otherwise use 238...
37229 SUB L ...less the horizontal screen position.
37230 LD E,A Keep the result in E.
FindHitPosition_Store 37231 LD (43940),HL Store the position in CollisionBox.
37234 LD (43942),DE Store the size in 43942.
37238 LD A,H Fetch the vertical screen position.
37239 SUB D Subtract the collision flag.
37240 LD (23582),A Store the result in ScratchPair.
37243 RET Return.
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