Through the Trap Door: Routine at 53083

53083: Attempt to spawn a new worm

Used by the routine at 52860.

Input
IX	Address of complex state data (current level) for worm

53083

LD A,60

Load A with a random number, 0-59...

53085

CALL 54222

...

53088

OR A

If random number is not zero (59 in 60 chance)...

53089

RET NZ

...then return

53090

LD A,(34218)

Set worm's current room to same as current character's...

53093

LD (IX+0),A

...

53096

CALL 53848

Store room size data for worm's current room

53099

LD A,(34235)

Load A with width of current room (chars) + 99...

53102

SUB 100

...and subtract 100 to get x-coordinate (zero-based) of right side of the room

53104

CALL 54222

Load A with a random x-coordinate within current room

53107

ADD A,100

Add 100 to restore coordinate system

53109

LD (IX+5),A

Set this as the worm's left x-coordinate

53112

ADD A,2

Add two to this...

53114

LD (IX+7),A

...and set as the worm's right x-coordinate

53117

LD A,2

Load A with a random number, 1-2...

53119

CALL 54222

...

53122

INC A

...

53123

LD (IX+1),A

...and assign the worm this depth

53126

LD A,124

Load A with 124 (y-coordinate of character row below bottom of room)

53128

SUB (IX+1)

Subtract worm's depth value to get its bottom y-coordinate...

53131

LD (IX+6),A

...and assign

53134

PUSH AF

Store AF (A = bottom y-coordinate of worm)

53135

LD (IX+4),121

Set worm's top y-coordinate to 121

53139

CALL 54768

Check entity at IX for collision with another entity at same depth whose interaction-(11,6) flag is set

53142

POP BC

Store AF (B = bottom y-coordinate of worm)

53143

JR NC,53154

If a collision occurred then set worm's depth to zero and return

53145

LD (IX+4),B

Set worm's top y-coordinate to same as its bottom y-coordinate

53148

LD HL,52735

Point HL at script data for worm rising from floor...

53151

JP 48098

...and execute

53154

LD (IX+1),0

Set worm's depth to zero

53158

RET

Return