Routines
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751F: Mirror Bitmap.
Used by the routines at Vector_Main and Screen_DrawColumn.
Input
HL Frame index
BitmapMirror 751F ADD HL,HL Get correct sprite data address from index.
7520 ADD HL,HL
7521 LD DE, BitmapData_E
7524 ADD HL,DE
7525 LD E,(HL) Get offset to bitmap
7526 INC HL
7527 LD D,(HL)
7528 INC HL
7529 LD A,(HL) Get height in chars.
752A AND $7F
752C LD C,A
752D INC HL
752E LD A,(HL) Get width in chars.
752F XOR $80
7531 LD (HL),A
7532 AND $7F
7534 LD HL,BmpStart_E Convert offset into true bitmap address
7537 ADD HL,DE
7538 EX DE,HL
7539 LD L,A
753A LD H,$00
753C LD (Blit_Width),HL
753F SRL A
7541 ADC A,$00
7543 LD (Blit_1),A
BitmapMirror_0 7546 LD B,$08
BitmapMirror_1 7548 PUSH BC
7549 LD HL,(Blit_Width)
754C ADD HL,DE
754D PUSH HL
754E LD A,(Blit_1)
7551 LD B,A
7552 AND A
BitmapMirror_2 7553 DEC HL
7554 LD A,(DE)
7555 LD C,(HL)
7556 RLA
7557 RR C
7559 RLA
755A RR C
755C RLA
755D RR C
755F RLA
7560 RR C
7562 RLA
7563 RR C
7565 RLA
7566 RR C
7568 RLA
7569 RR C
756B RLA
756C RR C
756E RLA
756F LD (DE),A
7570 LD (HL),C
7571 INC DE
7572 DJNZ BitmapMirror_2
7574 POP DE
7575 POP BC
7576 DJNZ BitmapMirror_1
7578 DEC C
7579 JR NZ,BitmapMirror_0
757B RET
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