|
Routines |
| Prev: 47703 | Up: Map | Next: 47797 |
|
||||||||
| 47731 | PUSH AF | Store AF (A = y-coordinate of menu hand cursor) | ||||||
| 47732 | LD A,(23408) | Load A with x-coordinate of left edge of current window to draw (characters) | ||||||
| 47735 | ADD A,2 | Add 2, as menu hand cursor is two characters wide... | ||||||
| 47737 | LD C,A | ...and load into C (x-coordinate of start of row of text in menu) | ||||||
| 47738 | POP AF | Restore AF (A = y-coordinate of menu hand cursor) | ||||||
| 47739 | ADD A,5 | Add five (as the "finger" of the cursor naturally points five pixels below the cursor's actual position) | ||||||
| 47741 | CALL 40658 | Divide this new y-coordinate by eight to get y-coordinate in characters | ||||||
| 47744 | LD B,A | Load this y-coordinate into B | ||||||
| 47745 | LD A,(23456) | Load initial y-coordinate of top of hand cursor relative to current window, into A | ||||||
| 47748 | ADD A,B | Add this to y-coordinate of "finger" | ||||||
| 47749 | LD B,A | Load this into B, so that B now contains y-coordinate of "finger" relative to top of window (characters) | ||||||
| 47750 | LD A,(23409) | Load y-coordinate of top edge of current window into A | ||||||
| 47753 | ADD A,B | Add... | ||||||
| 47754 | INC A | ...then add one (for window frame at top) so we now have absolute y-coordinate of "finger" | ||||||
| 47755 | LD B,A | Load into B | ||||||
| 47756 | LD (23476),BC | Store coordinates at 23476 | ||||||
| 47760 | CALL 63219 | Point HL at attribute file address for character coordinates x=C, y=B | ||||||
| 47763 | LD A,(23408) | Load B with x-coordinate of left edge of current window to draw (characters)... | ||||||
| 47766 | LD B,A | ... | ||||||
| 47767 | LD A,(23410) | Load A with x-coordinate of right edge of current window... | ||||||
| 47770 | SUB B | ...and subtract x-coordinate of left edge to get width | ||||||
| 47771 | DEC A | Decrease width by one to take into account window frame width... | ||||||
| 47772 | LD B,A | ...and load into B | ||||||
| 47773 | LD A,(HL) | Load attribute at current position in attribute file into A | ||||||
| 47774 | AND 56 | Reset INK, BRIGHT and FLASH bits, preserving PAPER only | ||||||
| 47776 | RRCA | Shift PAPER bits into INK bit slots... | ||||||
| 47777 | RRCA | ... | ||||||
| 47778 | RRCA | ... | ||||||
| 47779 | LD C,A | Store this value (new INK colour) in C | ||||||
| 47780 | LD A,(HL) | Load attribute at current position in attribute file into A | ||||||
| 47781 | RLCA | Shift all bits right by three (i.e. INK bits now contain former PAPER colour)... | ||||||
| 47782 | RLCA | ... | ||||||
| 47783 | RLCA | ... | ||||||
| 47784 | AND 56 | Reset INK, BRIGHT and FLASH bits, preserving PAPER only (i.e. PAPER bits now contain former INK colour) | ||||||
| 47786 | OR C | Merge modified PAPER value back in, to give new attribute (i.e. swapped INK and PAPER colours)... | ||||||
| 47787 | LD C,A | ...and load into C | ||||||
| 47788 | LD A,(HL) | Load attribute at current position in attribute file into A | ||||||
| 47789 | AND 192 | Reset INK and PAPER bits, preserving BRIGHT and FLASH only... | ||||||
| 47791 | OR C | ...and merge in swapped INK and PAPER values | ||||||
| 47792 | LD (HL),A | Write this new attribute value back to the attribute file | ||||||
| 47793 | INC HL | Advance HL to next byte in attribute file | ||||||
| 47794 | DJNZ 47792 | Decrease B (remaining number of characters to invert) and loop back to 47792 for next character block | ||||||
| 47796 | RET | Return | ||||||
| Prev: 47703 | Up: Map | Next: 47797 |