Krakout: Check whether the just-finished score makes the high-score table

B412: Check whether the just-finished score makes the high-score table

Decides on game over whether the score earns a place in the high-score table. A tie or better goes to name entry.
check_highscore	B412	CALL clear_screen
	B415	LD A,$47	Fill the attributes with bright white on black.
	B417	CALL fill_attrs	Fill the attributes with bright white on black.
	B41A	LD HL,score_units	Clear the print terminator on the live score's last digit, so every digit compares as plain ASCII against the table entries.
	B41D	RES 7,(HL)
	B41F	LD DE,score_display	Walk the live score against the table entries, highest first.
	B422	LD HL,highscore_entries
	B425	LD B,$0A
One table entry's turn. The slot counter counts down from 10 at the top slot to 1 at the bottom. An entry that qualifies hands the name entry the matched record, the live score and the slot counter.
highscore_compare_entry	B427	PUSH BC	Save the two cursors and the slot counter, then ready the digit compare.
	B428	PUSH DE
	B429	PUSH HL
	B42A	LD B,$08
The score is fixed-width, zero-padded ASCII, so a plain byte compare of the eight digits ranks two of them. The first digit where the live score is greater qualifies it and branches to name entry. A smaller digit abandons the entry and steps to the next record. All eight equal is a tie, and it qualifies.
highscore_compare_digit	B42C	LD A,(DE)	Compare one digit: live score against table entry.
	B42D	CP (HL)	Compare one digit: live score against table entry.
	B42E	JR Z,highscore_digit_equal	Equal digit: compare the next one.
	B430	JR NC,enter_highscore_name	Live digit higher: the score beats this entry, go enter the name.
	B432	JR highscore_next_entry	Live digit lower: this entry outranks the score, try the next.
highscore_digit_equal	B434	INC HL	Step to the next (less-significant) digit; all 8 matched falls through.
	B435	INC DE
	B436	DJNZ highscore_compare_digit
	B438	JR enter_highscore_name	All 8 digits equal: a tie qualifies too.
highscore_next_entry	B43A	POP HL	Reject this entry: advance the table cursor by the 22-byte record stride, restore the live-score cursor, and loop to the next-lower entry.
	B43B	LD DE,$0016
	B43E	ADD HL,DE
	B43F	POP DE
	B440	POP BC
	B441	DJNZ highscore_compare_entry
	B443	JP draw_highscore_table	Score below all 10 entries: redisplay the table without name entry.

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Routines