Routines
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62600: Draw Colour Flash Rectangle
Used by the routine at Extra_Life_Flash.
Renders one frame of the extra life colour flash animation. The frame index in A controls the inset from the edges: 11 paints a narrow band near the centre of the attribute area; 0 fills the full screen border. Each call fills the top row, the left and right border cells of each middle row, and the bottom row with the flash colour.
Input
A Frame index (0-11); lower values produce a wider rectangle
Draw_Colour_Flash_Rectangle 62600 LD HL,22528 Point to the start of the attribute area.
62603 LD C,A Copy the frame index to BC and DE.
62604 LD B,0
62606 LD E,A
62607 LD D,0
62609 SLA E Shift DE left by 5 to compute the attribute row offset.
62611 RL D
62613 SLA E
62615 RL D
62617 SLA E
62619 RL D
62621 SLA E
62623 RL D
62625 SLA E
62627 RL D
62629 ADD HL,DE Point to the starting attribute cell for this frame.
62630 ADD HL,BC
62631 PUSH HL Stash the starting attribute address on the stack.
62632 LD A,32 Calculate the top row fill width and set the loop counter.
62634 SUB C
62635 SUB C
62636 LD B,A
62637 LD (50438),A Save the row fill width.
62640 LD A,(50439) Load the flash colour.
Fill the top row of the rectangle.
Draw_Colour_Flash_Rectangle_Top 62643 LD (HL),A Fill the top row with the flash colour.
62644 INC HL
62645 DJNZ Draw_Colour_Flash_Rectangle_Top
62647 POP HL Restore the row pointer and advance to the next attribute row.
62648 LD DE,32
62651 ADD HL,DE
62652 LD A,22 Calculate the middle row count; jump to Draw_Colour_Flash_Rectangle_Bottom if none.
62654 SUB C
62655 SUB C
62656 JR Z,Draw_Colour_Flash_Rectangle_Bottom
62658 LD B,A Set the middle section row counter.
62659 LD A,(50438) Calculate the stride to the far border cell and save it.
62662 DEC A
62663 LD E,A
62664 LD D,0
62666 LD (50436),DE
62670 LD A,(50439) Load the flash colour.
For each middle row, paint the left and right border cells.
Draw_Colour_Flash_Rectangle_Middle 62673 PUSH HL Paint the left and right border cells and advance to the next row.
62674 LD (HL),A
62675 LD DE,(50436)
62679 ADD HL,DE
62680 LD (HL),A
62681 POP HL
62682 LD DE,32
62685 ADD HL,DE
62686 DJNZ Draw_Colour_Flash_Rectangle_Middle
Fill the bottom row of the rectangle.
Draw_Colour_Flash_Rectangle_Bottom 62688 LD A,(50438) Set up to fill the bottom row with the flash colour.
62691 LD B,A
62692 LD A,(50439)
Draw_Colour_Flash_Rectangle_Bottom_Fill 62695 LD (HL),A Fill the bottom row with the flash colour.
62696 INC HL
62697 DJNZ Draw_Colour_Flash_Rectangle_Bottom_Fill
62699 RET Return.
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