The title screen looks somewhat empty, doesn't it? Well, let's fill it with highscores! Lazy as I am I'm storing the highscore scores and names in two separate texts which are simply displayed with the common display routine.

After Game Over we check for a new spot. If we manage to enter the list all lower entries are moved down. For now that happens automatically and only affects the scores. Name entry follows up next.



First the newly added text fields, note that '-' is used as line break and '*' as end of text marker.
Another note: If you default fill high scores always have an easily beatable top score. People like to be better than someone else.

HIGHSCORE_SCORE
          !text "00050000-"
          !text "00040000-"
          !text "00030000-"
          !text "00020000-"
          !text "00010000-"
          !text "00001000-"
          !text "00000300-"
          !text "00000100*"
          
HIGHSCORE_NAME
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL-"
          !text "SUPERNATURAL*"

In the title screen layout code we add the display routines:

          ;display high scores
          ;x,y pos of name
          lda #6
          sta PARAM1
          lda #10
          sta PARAM2
          lda #<HIGHSCORE_NAME
          sta ZEROPAGE_POINTER_1
          lda #>HIGHSCORE_NAME
          sta ZEROPAGE_POINTER_1 + 1
          jsr DisplayText
          
          ;x,y pos of score
          lda #25
          sta PARAM1
          lda #10
          sta PARAM2
          lda #<HIGHSCORE_SCORE
          sta ZEROPAGE_POINTER_1
          lda #>HIGHSCORE_SCORE
          sta ZEROPAGE_POINTER_1 + 1
          jsr DisplayText

And last but not least, the actual checking for a highscore. You'll see that the score is not actually kept in a variable. Instead the screen chars at the display are used to compare against the text.

;------------------------------------------------------------
;check if the player got a new highscore entry
;------------------------------------------------------------
!zone CheckForHighscore
CheckForHighscore
          lda #0
          sta PARAM1
          ldy #0
          
.CheckScoreEntry
          ldx #0
          sty PARAM2
          
.CheckNextDigit
          lda SCREEN_CHAR + ( 23 * 40 + 8 ),x
          cmp HIGHSCORE_SCORE,y
          bcc .NotHigher
          bne .IsHigher
          
          ;need to check next digit
          iny
          inx
          cpx #HIGHSCORE_SCORE_SIZE
          beq .IsHigher
          jmp .CheckNextDigit
          
.NotHigherinc PARAM1
          lda PARAM1
          cmp #HIGHSCORE_ENTRY_COUNT
          beq .NoNewHighscore
          
          ;y points somewhere inside the score, recalc next line pos
          lda PARAM2
          clcadc #( HIGHSCORE_SCORE_SIZE + 1 )
          tay
          jmp .CheckScoreEntry
          
.NoNewHighscorejmp TitleScreen
          
.IsHigher;shift older entries down, add new entry
          lda #( HIGHSCORE_ENTRY_COUNT - 1 )
          sta PARAM2
          
          ;y carries the offset in the score text, position at start of second last entry
          ldy #( ( HIGHSCORE_SCORE_SIZE + 1 ) * ( HIGHSCORE_ENTRY_COUNT - 2 ) )
          
.CopyScore
          lda PARAM2
          cmp PARAM1
          beq .SetNewScore
          
          ;copy score
          ldx #0
          
.CopyNextScoreDigit
          lda HIGHSCORE_SCORE,y
          sta HIGHSCORE_SCORE + ( HIGHSCORE_SCORE_SIZE + 1 ),y
          iny
          inx
          cpx #HIGHSCORE_SCORE_SIZE
          bne .CopyNextScoreDigit
          tya
          sec
          sbc #( HIGHSCORE_SCORE_SIZE + HIGHSCORE_SCORE_SIZE + 1 )
          tay
          dec PARAM2
          jmp .CopyScore
          
.SetNewScore;y points at score above the new entry
          tya
          clcadc #( HIGHSCORE_SCORE_SIZE + 1 )
          tay
          ldx #0
          
.SetNextScoreDigit
          lda SCREEN_CHAR + ( 23 * 40 + 8 ),x
          sta HIGHSCORE_SCORE,y
          iny
          inx
          cpx #HIGHSCORE_SCORE_SIZE
          bne .SetNextScoreDigit
          jmp TitleScreen

step22.zip

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