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4. Making more room: Script pointers





First we'd like to do some space management.



; A = index #

; $49D1 = 2-byte PC table



[0049B2] 49b2 11 D1 49    LD DE,49D1h      AF=031B BC=0008 DE=C9C2 HL=49A6 SP=CAFC IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049B5] 49b5 CD C9 49    CALL 49C9h       AF=031B BC=0008 DE=49D1 HL=49A6 SP=CAFC IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]



[0049C9] 49c9 6F          LD L,A           AF=031B BC=0008 DE=49D1 HL=49A6 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049CA] 49ca 26 00       LD H,00h         AF=031B BC=0008 DE=49D1 HL=4903 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049CC] 49cc 29          ADD HL,HL        AF=031B BC=0008 DE=49D1 HL=0003 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049CD] 49cd 19          ADD HL,DE        AF=0300 BC=0008 DE=49D1 HL=0006 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049CE] 49ce 7E          LD A,(HL)        AF=0300 BC=0008 DE=49D1 HL=49D7 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049CF] 49cf 23          INC HL           AF=8200 BC=0008 DE=49D1 HL=49D7 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049D0] 49d0 66          LD H,(HL)        AF=8200 BC=0008 DE=49D1 HL=49D8 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049D1] 49d1 6F          LD L,A           AF=8200 BC=0008 DE=49D1 HL=4BD8 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0049D2] 49d2 E9          LD PC,HL         AF=8200 BC=0008 DE=49D1 HL=4B82 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]



; -------------------------------------------------------------------



; ~193 instances found, but scattered. Not contiguous.



; Relative pointer.



[004B82] 4b82 21 12 00    LD HL,0012h      AF=8200 BC=0008 DE=49D1 HL=4B82 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[004B85] 4b85 C3 BA 59    JP 59BAh         AF=8200 BC=0008 DE=49D1 HL=0012 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]



; -------------------------------------------------------------------



; Pointer table lookup ($0E bytes)



[0059BA] 59ba 3E 02       LD A,02h         AF=8200 BC=0008 DE=49D1 HL=0012 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

[0059BC] 59bc 32 FF FF    LD (FFFFh),A     AF=0200 BC=0008 DE=49D1 HL=0012 SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=0C000 [ROM]

...

[0059C7] 59c7 C3 3A 33    JP 333Ah         AF=BE00 BC=0008 DE=80B0 HL=84BE SP=CAFA IX=C880 IY=C800 V    P0=00000 P1=04000 P2=08000 [ROM]



; _____________________________________________________________________



We have 2 text banks. One uses relative pointers and the other hard-coded.



$80B2-835B is the 2-byte pointer table ($2AA size) for $59BA.



We can convert these to hard-coded pointers and free the space.