Routines
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59607: Handle Weapon Pickup
Handler for the object types 104 to 107 the four weapons that Sabreman can pick up (see Sprite_Weapon_1). The weapons are the small object records at Small_Object_Records. Byte 7 of a record holds the flags: bit 0 is set if there is no old image to erase, bit 1 is set while Sabreman carries the weapon and bit 2 is set while the weapon falls.
A weapon that lies on the floor is drawn again and again. When an action key has just been pressed (the flag at New_Action_Key_Press_Flag is 255) and Sabreman is touching it (see Check_Sabreman_Contact), he picks it up: the weapon moves to the x position 136 and the y position 15 which is its place in the panel at the top of the screen, bit 1 of the flags is set, the flag at New_Action_Key_Press_Flag is set to 254 to show that the key press has been used, and the type of the weapon is stored in the first of the weapon slots at Weapon_Slots.
Each later key press moves a carried weapon 24 pixels to the right in the panel and stores its type in the weapon slot that goes with the new x position (the x positions 160 and 184 both give the third slot, and none gives the second). A key press when the weapon has reached 184 makes Sabreman drop it. It is put at his position, with bit 1 of the flags reset, bit 2 set and the counter in byte 6 set to 16 and it falls (see Handle_Weapon_Pickup_Fall).
A weapon that is in a different room is dealt with by Handle_Distant_Weapon.
Input
IX Small object record of the weapon
Handle_Weapon_Pickup 59607 CALL StoreEntity Save the state of the weapon.
59610 BIT 1,(IX+7) Jump to Handle_Weapon_Pickup_Carried if Sabreman is carrying the weapon.
59614 JR NZ,Handle_Weapon_Pickup_Carried
59616 LD A,(36636) Fetch the room x of Sabreman.
59619 CP (IX+2) Jump to Handle_Distant_Weapon if the weapon is in a different room x.
59622 JP NZ,Handle_Distant_Weapon
59625 LD A,(36638) Fetch the room y of Sabreman.
59628 CP (IX+4) Jump to Handle_Distant_Weapon if the weapon is in a different room y.
59631 JP NZ,Handle_Distant_Weapon
59634 BIT 0,(IX+7) Jump to Update_Object_Sprite_Using_Flags if it has no old image to erase.
59638 JP NZ,Update_Object_Sprite_Using_Flags
59641 BIT 2,(IX+7) Jump to Handle_Weapon_Pickup_Fall if the weapon is falling.
59645 JP NZ,Handle_Weapon_Pickup_Fall
59648 LD A,(36586) Fetch the flag for a new action key press.
59651 AND A Jump to Handle_Weapon_Pickup_Draw if no action key has been pressed.
59652 JR Z,Handle_Weapon_Pickup_Draw
59654 INC A Jump to Handle_Weapon_Pickup_Draw if the key press has been used already (the flag is not 255).
59655 JR NZ,Handle_Weapon_Pickup_Draw
59657 CALL Check_Sabreman_Contact Check for contact with Sabreman.
59660 BIT 2,C Jump to Handle_Weapon_Pickup_Draw if Sabreman is not touching the weapon.
59662 JR Z,Handle_Weapon_Pickup_Draw
59664 LD (IX+1),136 Set the x position of the weapon to 136.
59668 LD (IX+3),15 Set the y position of the weapon to 15.
59672 SET 1,(IX+7) Set bit 1 of the flags, as Sabreman carries the weapon.
59676 LD A,254 Mark the key press as used by writing 254 to New_Action_Key_Press_Flag.
59678 LD (36586),A
59681 LD A,(IX+0) Fetch the type of the weapon.
59684 LD (36587),A Store it in the first weapon slot.
59687 JP Update_Object_Sprite_Using_Flags Jump to Update_Object_Sprite_Using_Flags.
Handle_Weapon_Pickup_Carried 59690 RES 0,(IX+7) Reset bit 0 of the flags.
59694 LD A,(36586) Fetch the flag for a new action key press.
59697 AND A Jump to Handle_Weapon_Pickup_Draw if no action key has been pressed.
59698 JR Z,Handle_Weapon_Pickup_Draw
59700 LD A,(IX+1) Fetch the x position of the weapon.
59703 ADD A,24 Add 24 to move it to the next place in the panel.
59705 CP 200 Jump to Handle_Weapon_Pickup_Next_Slot if the result is less than 200.
59707 JR C,Handle_Weapon_Pickup_Next_Slot
59709 LD HL,(36635) Fetch the x position and the room x of Sabreman.
59712 LD (IX+1),L Set the x position of the weapon.
59715 LD (IX+2),H Set the room x of the weapon.
59718 LD HL,(36637) Fetch the y position and the room y of Sabreman.
59721 LD (IX+3),L Set the y position of the weapon.
59724 LD (IX+4),H Set the room y of the weapon.
59727 RES 1,(IX+7) Reset bit 1 of the flags, as the weapon is dropped.
59731 SET 2,(IX+7) Set bit 2 of the flags, as the weapon falls.
59735 LD (IX+6),16 Set the counter in byte 6 to 16.
59739 JP Update_Object_Sprite_Using_Flags Jump to Update_Object_Sprite_Using_Flags.
Handle_Weapon_Pickup_Next_Slot 59742 LD (IX+1),A Set the x position of the weapon.
59745 RRA Shift the x position right four times.
59746 RRA
59747 RRA
59748 RRA
59749 AND %00000011 Keep only the two low bits.
59751 CP 3 Jump to Handle_Weapon_Pickup_Store_Slot unless the result is 3.
59753 JR NZ,Handle_Weapon_Pickup_Store_Slot
59755 DEC A Change 3 to 2.
Handle_Weapon_Pickup_Store_Slot 59756 LD E,A Store the weapon slot number in E.
59757 LD D,0 Clear the high byte of the slot number.
59759 LD HL,36587 Point HL at Weapon_Slots.
59762 ADD HL,DE Add the slot number to point at the weapon slot.
59763 LD A,(IX+0) Fetch the type of the weapon.
59766 LD (HL),A Store it in the weapon slot.
59767 JP Update_Object_Sprite_Using_Flags Jump to Update_Object_Sprite_Using_Flags.
Handle_Weapon_Pickup_Draw 59770 CALL PrepDraw2 Prepare the sprite of the weapon.
59773 JP ColourEntity Jump to ColourEntity.
The weapon falls. The counter in byte 6 goes up on every call and one sixteenth of it is added to the y position.
Handle_Weapon_Pickup_Fall 59776 LD A,(IX+6) Fetch the counter.
59779 INC (IX+6) Add one to the counter.
59782 RRA Divide the old value by sixteen.
59783 RRA
59784 RRA
59785 RRA
59786 AND %00001111 Keep only the low four bits.
59788 ADD A,(IX+3) Add the y position of the weapon.
59791 LD (IX+3),A Set the y position of the weapon.
59794 CALL Check_Decoration_Contact Check for contact with the decorations.
59797 BIT 2,C Jump to Handle_Weapon_Pickup_Check_Floor if the weapon is not touching a decoration.
59799 JR Z,Handle_Weapon_Pickup_Check_Floor
59801 LD A,B Copy 160 less the y position of the top of the decoration to A.
59802 NEG Negate it.
59804 ADD A,161 Add 161 to get the y position just below the top of the decoration.
59806 LD (IX+3),A Set the y position of the weapon.
59809 RES 2,(IX+7) Reset bit 2 of the flags, as the weapon has stopped falling.
59813 JP Update_Object_Sprite_Using_Flags Jump to Update_Object_Sprite_Using_Flags.
Handle_Weapon_Pickup_Check_Floor 59816 LD A,(IX+3) Fetch the y position of the weapon.
59819 CP 159 Jump to Update_Object_Sprite_Using_Flags if it is less than 159.
59821 JP C,Update_Object_Sprite_Using_Flags
59824 CALL Read_World_Map Read the world map entry of the room that the weapon is in. The flags of the room are returned in E.
59827 BIT 4,E Jump to Handle_Weapon_Pickup_Check_Bottom if the room has no floor.
59829 JR Z,Handle_Weapon_Pickup_Check_Bottom
59831 LD (IX+3),159 Set the y position of the weapon to 159 which is the floor.
59835 RES 2,(IX+7) Reset bit 2 of the flags, as the weapon has stopped falling.
59839 JP Update_Object_Sprite_Using_Flags Jump to Update_Object_Sprite_Using_Flags.
Handle_Weapon_Pickup_Check_Bottom 59842 LD A,(IX+3) Fetch the y position of the weapon.
59845 CP 191 Jump to Update_Object_Sprite_Using_Flags if it is less than 191.
59847 JP C,Update_Object_Sprite_Using_Flags
Handle_Weapon_Pickup_Next_Room 59850 INC (IX+4) Move the weapon to the room below.
59853 CALL Read_World_Map Read the world map entry of the room that the weapon is in.
59856 BIT 4,E Jump back to Handle_Weapon_Pickup_Next_Room if the room has no floor.
59858 JR Z,Handle_Weapon_Pickup_Next_Room
59860 LD (IX+3),158 Set the y position of the weapon to 158.
59864 LD (IX+6),0 Clear the counter in byte 6.
59868 JP RemoveEntity Erase the sprite of the weapon.
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