Grammer2/src/gfx/bigtile.z80

;===========================================================
bigtile:
;===========================================================
;Inputs:
;     A is the method:
;        0=Overwrite
;        1=AND
;        2=XOR
;        3=OR
;        4=Swap
;        5=Erase
;        6=Mask
;        7=Gray
;     B is the width (in bytes)
;     C is the height (in pixels)
;     DE points to the sprite data
;     HL points to the output location
;Outputs:
;     HL is A*12 larger (next sprite down?)
;     DE points to the next byte after the sprite data
;     A is 0
;     B is not changed
;     C is 12-B
;===========================================================
  push af
  ld a,c
  di
  ex af,af'
  ld a,12
  sub b
  ld c,a
  pop af
OverwriteXxY:
  or a
  jr nz,ANDXxY
  ex af,af'
_:
  ex de,hl
  push bc
  ldi
  inc bc
  djnz $-3
  ex de,hl
  add hl,bc
  pop bc
  dec a
  jr nz,-_
  ret
ANDXxY:
  dec a
  jr nz,XORXxY
  ex af,af'
_:
  push bc
  push af
  ld a,(de)
  and (hl)
  ld (hl),a
  inc de
  inc hl
  djnz $-5
  add hl,bc
  pop af
  pop bc
  dec a
  jr nz,-_
  ret
XORXxY:
  dec a
  jr nz,ORXxY
  ex af,af'
_:
  push bc
  push af
  ld a,(de)
  xor (hl)
  ld (hl),a
  inc de
  inc hl
  djnz $-5
  add hl,bc
  pop af
  pop bc
  dec a
  jr nz,-_
  ret
ORXxY:
  dec a
  jr nz,SwapXxY
  ex af,af'
_:
  push bc
  push af
  ld a,(de)
  or (hl)
  ld (hl),a
  inc de
  inc hl
  djnz $-5
  add hl,bc
  pop af
  pop bc
  dec a
  jr nz,-_
  ret
SwapXxY:
  dec a
  jr nz,EraseXxY
  ex af,af'
  ld c,12
_:
  push bc
  push af
  ld a,(de)
  ldi
  dec hl
  ld (hl),a
  inc hl
  djnz $-6
  add hl,bc
  pop af
  pop bc
  dec a
  jr nz,-_
  ret
EraseXxY:
  dec a
  jr nz,MaskXxY
  ex af,af'
  push bc
  push af
_:
  ld a,(de)
  cpl
  and (hl)
  ld (hl),a
  inc de
  inc hl
  djnz -_
  add hl,bc
  pop af
  pop bc
  dec a
  jr nz,-_-2
  ret
MaskXxY:
  dec a
  jr nz,GrayXxY
  ex af,af'
_:
  push bc
  push af
  ex de,hl
  ld a,(de)
  and (hl)
  inc hl
  or (hl)
  ld (de),a
  inc de
  inc hl
  djnz $-7
  ex de,hl
  add hl,bc
  pop af
  pop bc
  dec a
  jr nz,-_
  ret
GrayXxY:
  bit grayFlag,(iy+InternalFlag)
  ld a,55h
  jr z,$+3
  rrca
  ex af,af'
_:
  push bc
  push af
  ex af,af'
  ld (hl),a
  ex de,hl
  and (hl)
  inc hl
  or (hl)
  inc hl
  ex de,hl
  push af
  ld a,(hl)
  ex af,af'
  pop af
  ld (hl),a
  inc hl
  djnz $-14
  add hl,bc
  ex af,af'
  rlca
  ex af,af'
  pop af
  pop bc
  dec a
  jr nz,-_
  ret