Routines
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44221: Move Player To Room
Used by the routine at ChangeRoom.
Moves the player to a new room. Before updating the current room, it moves every scenic-event item from Table_ScenicEventItems that is present into the destination room (so those events follow the player). It then writes the destination to CurrentRoom and, for each set bit in Flags_EventStates, brings the matching byte from Data_PhraseTokens into the new room via Handler_UpdateItemEventCurrentRoom.
Input
A Destination room ID
Store the destination room ID and prepare to update scenic events.
MovePlayerToRoom 44221 LD C,A Copy the destination room ID into C.
44222 LD A,(48079) Jump to MovePlayerToRoom_SetRoom if *Count_ScenicEvents is zero.
44225 AND A
44226 JR Z,MovePlayerToRoom_SetRoom
Loop through the scenic items at Table_ScenicEventItems and move any that are present into the destination room.
44228 LD B,A Copy the scenic-event count from A into B as the loop counter.
44229 LD HL,46778 Point HL at the scenic event items table at Table_ScenicEventItems.
44232 JR ScenicItem_Next Jump to ScenicItem_Next.
ScenicItem_Advance 44234 INC HL Move HL on to the next scenic event item ID.
ScenicItem_Next 44235 LD A,(HL) Fetch this scenic event's item ID from Table_ScenicEventItems into A.
44236 CALL ValidateItemPresent Call ValidateItemPresent to test whether that item is present.
44239 JR NZ,ScenicItem_Count Jump to ScenicItem_Count if the item is not present.
This scenic item is present, so move it to the destination room.
44241 PUSH HL Stash the scenic table pointer and loop counter on the stack.
44242 PUSH BC
44243 LD B,(HL) Copy the scenic item ID into B.
44244 CALL Handler_UpdateItemLocation Call Handler_UpdateItemLocation to place that item in the destination room held in C.
44247 POP BC Restore the loop counter and scenic table pointer from the stack.
44248 POP HL
ScenicItem_Count 44249 DJNZ ScenicItem_Advance Decrease the scenic-event counter by one and loop back to ScenicItem_Advance until all scenic events have been checked.
Update the current room ID to the destination room.
MovePlayerToRoom_SetRoom 44251 LD A,C Write the destination room ID from C to CurrentRoom.
44252 LD (41222),A
44255 LD A,(41169) Fetch *Flags_EventStates into A and return if no event flag is set.
44258 AND A
44259 RET Z
For each set bit in Flags_EventStates, bring the corresponding byte from Data_PhraseTokens into the current room.
44260 LD B,8 Set a counter in B for 8 bits.
44262 LD HL,46836 Point HL at Data_PhraseTokens.
44265 LD C,A Copy the event flags into C for bit testing.
44266 JR EventFlag_Next Jump to EventFlag_Next.
EventFlag_Advance 44268 INC HL Move HL on to the next event item ID.
EventFlag_Next 44269 SRL C Shift the event flags right to test the next bit.
44271 JR NC,EventFlag_Count Jump to EventFlag_Count if this bit is not set.
This event bit is set, so bring its item into the current room.
44273 LD A,(HL) Fetch the item ID from Data_PhraseTokens into A.
44274 PUSH HL Stash the table pointer and bit counter on the stack.
44275 PUSH BC
44276 CALL Handler_UpdateItemEventCurrentRoom Call Handler_UpdateItemEventCurrentRoom to move that item into the current room.
44279 POP BC Restore the bit counter and table pointer from the stack.
44280 POP HL
EventFlag_Count 44281 DJNZ EventFlag_Advance Decrease the bit counter by one and loop back to EventFlag_Advance until all 8 bits have been tested.
MovePlayerToRoom_Return 44283 RET Return.
View the equivalent code in;
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