Routines
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50302: Initialise Special Objects
Used by the routine at InitialiseGame.
Chooses the objects in SpecialObjectsTable at the start of a game. Each is given a graphic number from 96 to 103 taken from a number made from the random number seed and the refresh register. The starting position of each entry is copied to the current position.
Stir the seed and fill the table.
InitialiseSpecialObjects 50302 LD HL,28658 Point HL at the first special object, SpecialObjectsTable.
50305 LD A,(23456) Fetch the first random seed from RandomSeed1.
50308 LD E,A Keep it in E.
50309 LD A,R Fetch the refresh register.
50311 ADD A,E Add the seed to it.
50312 LD E,A Keep the result in E.
InitialiseSpecialObjects_Next 50313 LD A,E Copy the number to A.
50314 AND %00000111 Keep bits 0 to 2.
50316 OR %01100000 Make it a graphic number from 96 to 103.
50318 LD (HL),A Set the graphic number of the object.
50319 INC HL Move on to the starting position.
50320 INC E Change the number, for the next object.
50321 PUSH DE Stash the number on the stack.
50322 EX DE,HL Swap the entry pointer into DE.
50323 LD HL,4 Set HL to 0004.
50326 ADD HL,DE Add it to the starting position.
50327 EX DE,HL Swap the pointers back.
50328 LD BC,4 Set BC to 0004.
50331 LDIR Copy the starting position and room.
50333 EX DE,HL Point HL at the next object.
50334 PUSH HL Stash the next entry on the stack.
50335 LD BC,28946 Point BC at SpriteTable.
50338 AND A Subtract SpriteTable from HL.
50339 SBC HL,BC
50341 POP HL Restore the address of the next object from the stack.
50342 POP DE Restore the number from the stack.
50343 JR C,InitialiseSpecialObjects_Next Jump to InitialiseSpecialObjects_Next until every object has been done.
50345 RET Return.
View the equivalent code in;
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