Routines
Prev: C991 Up: Map Next: C9DA
C9B3: Copy Attributes
Not used. Copies attributes from the bytes that follow the width and height of an area, rather than filling the area with one value as FillAttributes does.
Input
DE Address of the area
HL Position (H is the pixel row and L is the pixel column)
CopyAttributes C9B3 PUSH HL Stash HL on the stack.
C9B4 LD A,(DE) Read DE.
C9B5 LD B,A B=A.
C9B6 INC DE Advance DE.
C9B7 LD A,(DE) Read DE.
C9B8 LD C,A C=A.
C9B9 CALL AttributeAddress Call AttributeAddress.
C9BC LD A,B A=B.
C9BD LD ($5C1C),A The width of the attribute area.
C9C0 INC DE Advance DE.
CopyAttributes_Row C9C1 PUSH HL Stash HL on the stack.
C9C2 LD A,($5C1C) The width of the attribute area.
C9C5 LD B,A B=A.
CopyAttributes_Byte C9C6 LD A,(DE) Read DE.
C9C7 LD (HL),A Write A where HL points.
C9C8 INC DE Advance DE.
C9C9 INC HL Advance HL.
C9CA DJNZ CopyAttributes_Byte Decrease B and jump to CopyAttributes_Byte until none remain.
C9CC POP HL Bring HL back off the stack.
C9CD PUSH DE Stash DE on the stack.
C9CE LD DE,$0020 DE=20.
C9D1 AND A Is A zero?
C9D2 SBC HL,DE Subtract DE and the carry from HL.
C9D4 POP DE Bring DE back off the stack.
C9D5 DEC C Step C back.
C9D6 JR NZ,CopyAttributes_Row Jump to CopyAttributes_Row if the zero flag is clear.
C9D8 POP HL Bring HL back off the stack.
C9D9 RET Return.
Prev: C991 Up: Map Next: C9DA