Routines
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28075: Handler: Cars
Used by the routine at Run_Main_Loop_Body.
Dispatches to the appropriate car handler based on the current room, then manages the car movement and crash animation. Cars move left across the screen and are randomised when they go off-screen. When hit by Percy's egg, a crash animation plays using frames 36-39 before the car resets.
Check if respawning; if so, reset the car state.
Handler_Cars 28075 LD A,(24507) Jump to Dispatch_Car_Handler if *RespawnFlag is unset.
28078 OR A
28079 JR Z,Dispatch_Car_Handler
28081 XOR A Write 0 to;
28082 LD (29192),A
28085 LD (29193),A
Dispatch to the correct car handler based on the current room.
Dispatch_Car_Handler 28088 LD A,(24517) Jump to Handler_CarType3 if *CurrentRoom is equal to 2.
28091 CP 2
28093 JP Z,Handler_CarType3
28096 CP 1 Jump to Handle_Car_Movement if the current room is equal to 1, else jump to Check_Room_09.
28098 JR NZ,Check_Room_09
28100 JR Handle_Car_Movement
Check_Room_09 28102 CP 9 Return if the current room is less than 9.
28104 RET C
28105 CP 9 Jump to Handler_CarType2 if the current room is equal to 9.
28107 JP Z,Handler_CarType2
Handle_Car_Movement 28110 CALL Handler_Car_Type1 Call Handler_Car_Type1.
28113 LD IX,56016 Point IX at Sprite04_3Wide_X_Position (car sprite data).
28117 LD A,(24507) Call Randomise_Car_Position if *RespawnFlag is set to randomise the car.
28120 OR A
28121 CALL NZ,Randomise_Car_Position
Check if the car is in the crash animation.
28124 LD A,(29193) Jump to Move_Car if *CarCrashCounter is zero, indicating there's been no crash.
28127 OR A
28128 JR Z,Move_Car
28130 CP 1 Jump to Crash_Animation_Done if the crash counter is equal to 1 (crash animation complete).
28132 JR Z,Crash_Animation_Done
Crash animation is playing; update the explosion frames.
28134 DEC A Decrement the crash counter and write it back to *CarCrashCounter.
28135 LD (29193),A
28138 AND %00000010 Mask and add 36 to select the front crash frame.
28140 ADD A,36
28142 LD (IX+3),A Write the frame to *IX+3 (front sprite).
28145 INC A Increment by one for the rear crash frame and write to *IX+7.
28146 LD (IX+7),A
28149 JR Check_Car_Percy_Collision Jump to Check_Car_Percy_Collision.
Crash animation complete; reset the crash counter.
Crash_Animation_Done 28151 XOR A Write 0 to *CarCrashCounter to clear it.
28152 LD (29193),A
28155 JR Check_Car_Percy_Collision Jump to Check_Car_Percy_Collision.
No crash; move the car left across the screen.
Move_Car 28157 LD HL,29195 Point HL at CarSpeed.
28160 LD A,(IX+0) Load the car's X position from *IX+0.
28163 SUB (HL) Subtract the car speed; if the car has gone off-screen (carry set), call Randomise_Car_Position to randomise a new car.
28164 CALL C,Randomise_Car_Position
28167 LD (IX+0),A Write the updated X position to *IX+0 (front X).
28170 ADD A,16 Set the rear X position to the front X plus 16.
28172 LD (IX+4),A
Sprite ID Sprite
30 udg44763-56x4
28175 LD (IX+3),30 Set the front sprite frame to 30 (car front).
Sprite ID Sprite
31 udg44795-56x4
28179 LD (IX+7),31 Set the rear sprite frame to 31 (car rear).
Check if Percy's egg has hit the car.
28183 LD BC,29193 Point BC at CarCrashCounter and HL at Sprite04_3Wide_X_Position.
28186 LD HL,56016
28189 LD A,(24489) Call CheckCarEggCollision_Test if *EggDropFlag is non-zero to check for an egg collision with the car.
28192 OR A
28193 CALL NZ,CheckCarEggCollision_Test
Check if the car has collided with Percy.
Check_Car_Percy_Collision 28196 LD IX,56000 Point IX at Percy_X_Position.
28200 LD IY,56016 Point IY at Sprite04_3Wide_X_Position (car sprite data).
28204 JP Handler_CarCheckPercyCollision_Test Jump to Handler_CarCheckPercyCollision_Test to check if the car has collided with Percy.
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