MapLoader.asm

#import "Constants.asm"

BasicUpstart2(start)

.label Row = $02B0
.label Col = $02B1
.label TileNumber = $02B2
.label FrameCounter = $02A8
.label BellFrameCounter = $02B3
.label ScrollFrameCounter = $02B4
.label Direction = $02B5

start:

    lda 1
    and #%11111110
    sta 1

    lda #BLACK
    sta EXTCOL
    lda #BLUE
    sta BGCOL0

    lda $DD00
    and #%11111100
    ora #%00000010      //<- your desired VIC bank value, Bank 1
    sta $DD00

    lda $D018
    and #%00000001
    ora #%00001000      //<- your desired CharMem bank value, Screem @ $4000, Character @ $6000
    sta $D018

    lda SCROLX
    and #%11110111
    ora #%00010000      // Set multicolour mode for characters
    sta SCROLX

    lda #BROWN 
    sta BGCOL1
    lda #GREY
    sta BGCOL2

    jsr DrawScreen          // Draw Map on the Screen

loop:
    sei
    lda #90                // Scanline -> A
    cmp RASTER              // Compare A to current raster line
    bne loop

    inc $D020

EndControls:
    inc FrameCounter        // increase frame counter
    lda FrameCounter
    and #127                // Only count 0 -> 127 (128 cycles)
    cmp #2                // 4 second frame counter (4 frames = .5 secs per frame)
    bne !ByPassReSet+
    lda #0                  // reset frame
    sta FrameCounter

    lda Direction
    beq !ByPassScroll+
    cmp #1
    bne DirectionLeft
    dec ScrollFrameCounter
    lda ScrollFrameCounter
    and #%00000111
    sta ScrollFrameCounter

    lda SCROLX
    and #%11111000
    ora ScrollFrameCounter
    sta SCROLX

    lda ScrollFrameCounter
    bne !ByPassScroll+
    jsr ScrollLeft
    jmp !ByPassScroll+

DirectionLeft:
    inc ScrollFrameCounter
    lda ScrollFrameCounter
    and #%00000111
    sta ScrollFrameCounter

    lda ScrollFrameCounter
    bne !ByPassScrollHere+
    jsr ScrollRight

!ByPassScrollHere:
    lda SCROLX
    and #%11111000
    ora ScrollFrameCounter
    sta SCROLX

!ByPassScroll:

    lda 197
    cmp #scanCode_A
    bne TestForDKey
    lda #1
    sta Direction
    jmp EndControls

TestForDKey:
    cmp #scanCode_D
    bne Nothing
    lda #2
    sta Direction
    jmp EndControls

Nothing:
    lda #0
    sta Direction

!ByPassReSet:
    cli

    dec $D020
    jmp loop

CalculateBellFrame:
    lda FrameCounter
    lsr  // /2
    lsr  // /4
    lsr  // /8
    lsr  // 16
    lsr  // 32
    //sta BellFrameCounter
    rts

DrawScreen:
    lda #<SCREENRAM + (5*40) 
    sta Screen
    lda #>SCREENRAM + (5*40) 
    sta Screen + 1

    lda #<COLOURRAM + (5*40) 
    sta Colour
    lda #>COLOURRAM + (5*40) 
    sta Colour + 1

    lda #<MAP_1
    sta MapTile
    lda #>MAP_1
    sta MapTile + 1

    lda #0
    sta Row

DrawRowLoop:
    lda #0
    sta Col

DrawColumnLoop:
    ldy #0

    lda #0
    sta TileCharLookup
    sta TileCharLookup + 1

    lda MapTile: $DEAD      // Get Current Tile Number

    sta TileNumber
    sta TileCharLookup

    asl TileCharLookup           // * 2
    rol TileCharLookup + 1
    asl TileCharLookup
    rol TileCharLookup + 1      // * 4

    clc 
    lda #<MAP_TILES
    adc TileCharLookup
    sta TileCharLookup
    lda #>MAP_TILES
    adc TileCharLookup + 1
    sta TileCharLookup + 1

DrawTile:
    lda TileCharLookup: $B00B, y        // get Tile Character

    ldx TileLocationOffSet,y            // Character Offset.
    sta Screen: $BABE, x

    ldx TileNumber
    lda COLOUR_TILES, x                  // Colour information for tile

    ldx TileLocationOffSet, y
    sta Colour: $BEEF,x                 // Character Colour Ram

    iny
    cpy #$04
    bne DrawTile

    LIBMATH_ADD8BITTO16BIT_AV(MapTile,$01)

    LIBMATH_ADD8BITTO16BIT_AV(Screen,$02)

    LIBMATH_ADD8BITTO16BIT_AV(Colour,$02)

    inc Col 
    ldx Col 
    cpx #$14
    beq EndDrawColumnLoop
    jmp DrawColumnLoop

 EndDrawColumnLoop:  
    LIBMATH_ADD8BITTO16BIT_AV(Screen,$28)

    LIBMATH_ADD8BITTO16BIT_AV(Colour,$28)

    inc Row 
    ldx Row 
    cpx #$0A
    beq EndDrawRowLoop
    jmp DrawRowLoop

EndDrawRowLoop:
    rts

TileLocationOffSet:
    .byte 0, 1, 40, 41

BellAnimationTiles:
    .byte 27, 29, 27, 31

* = $2000 "Map data"
    MAP_TILES:
        .import binary "..\02. CharPad\Quasidemo - Tiles.bin"
    
    COLOUR_TILES:
        .import binary "..\02. CharPad\Quasidemo - TileAttribs.bin"

    CHAR_ColourS:
        .import binary "..\02. CharPad\Quasidemo - CharAttribs.bin"
    
    MAP_1:
        .import binary "..\02. CharPad\Quasidemo - Map (20x11).bin"

* = $6000 "Chars data"
    CHARS:
        .import binary "..\02. CharPad\Quasidemo - Chars.bin"

.macro LIBMATH_ADD8BITTO16BIT_AV(AddAddress,AddValue)
{
    clc
    lda AddAddress
    adc #AddValue
    sta AddAddress
    lda AddAddress + 1
    adc #$00
    sta AddAddress + 1
}

.macro DrawTile(TileLocationZeroPage, TileScreen, TileColour)
{
    ldy #0
!Tile:
    lda (TileLocationZeroPage), y        // get Tile Character

    ldx TileLocationOffSet,y            // Character Offset.
    sta TileScreen, x

    ldx TileNumber
    lda COLOUR_TILES, x                  // Colour information for tile

    ldx TileLocationOffSet, y
    sta TileColour,x                 // Character Colour Ram

    iny
    cpy #$04
    bne !Tile-
}

    // inc FrameCounter        // increase frame counter
    // lda FrameCounter
    // and #127                // Only count 0 -> 127 (128 cycles)
    //cmp #128                // 4 second frame counter (4 frames = .5 secs per frame)
    //bne AnimateBell
    //lda #0                  // reset frame
    // sta FrameCounter

// AnimateBell:
    //jsr CalculateBellFrame  // work out which frame the bell is currently on

    //cmp BellFrameCounter    // Bell Frame Counter same as before, no need to re-draw frame
    //bne DrawBellFrame
//     jmp EvaluateSpriteControl

// DrawBellFrame:
//     sta BellFrameCounter

//     lda #0
//     sta ZeroPageLow
//     sta ZeroPageLow + 1
    
//     ldx BellFrameCounter
//     lda BellAnimationTiles,x    // get bell tile frame for the frame counter
//     sta TileNumber

//     sta ZeroPageLow             // work out tile character offset
//     asl ZeroPageLow             // * 2
//     rol ZeroPageLow + 1
//     asl ZeroPageLow
//     rol ZeroPageLow + 1         // * 4

//     clc 
//     lda #<MAP_TILES             // add offset to Map Tiles Address Location
//     adc ZeroPageLow
//     sta ZeroPageLow
//     lda #>MAP_TILES
//     adc ZeroPageLow + 1
//     sta ZeroPageLow + 1

//     DrawTile(ZeroPageLow, $4162, $D962)     // Draw Tile

//     LIBMATH_ADD8BITTO16BIT_AV(ZeroPageLow,$04)  
//     inc TileNumber
//     DrawTile(ZeroPageLow, $4164, $D964)     // Draw Next Tile

// EvaluateSpriteControl:

* = * "Scroll Right"
ScrollRight:
{
    .label Rows         = ZeroPageParam1
    .label Cols         = ZeroPageParam2
    .label ScreenLoc    = ZeroPageLow
    .label ColourLoc    = ZeroPageLow2

    .label CharTransfer = ZeroPageParam3
    .label ColTransfer = ZeroPageParam3

    .label StartOfScrollingScreen = SCREENRAM + (5 * 40)
    .label StartOfScrollingColour = COLOURRAM + (5 * 40)

RowColumnCollection:
    .for (var row=0; row<20; row++)
    {
        lda StartOfScrollingScreen + (row * 40) + 39
        pha
        lda StartOfScrollingColour + (row * 40) + 39
        pha 

        .for (var col=38; col>=0; col--)
        {
            lda StartOfScrollingScreen + (row * 40) + col
            sta StartOfScrollingScreen + (row * 40) + col + 1
            
            lda StartOfScrollingColour + (row * 40) + col
            sta StartOfScrollingColour + (row * 40) + col + 1
        }

    //     ldy #38
    // !ColumnLooper:
    //     lda StartOfScrollingScreen + (row * 40),y
    //     iny
    //     sta StartOfScrollingScreen + (row * 40),y
    //     dey

    //     lda StartOfScrollingColour + (row * 40),y
    //     iny
    //     sta StartOfScrollingColour + (row * 40),y
    //     dey

    //     dey
    //     bpl !ColumnLooper-

        pla
        sta StartOfScrollingColour + (row * 40)
        pla
        sta StartOfScrollingScreen + (row * 40)
    }
    rts
}

* = * "Scroll Left"
ScrollLeft:
{
    .label Rows         = ZeroPageParam1
    .label Cols         = ZeroPageParam2
    .label ScreenLoc    = ZeroPageLow
    .label ColourLoc    = ZeroPageLow2

    .label CharTransfer = ZeroPageParam3
    .label ColTransfer = ZeroPageParam3

    .label StartOfScrollingScreen = SCREENRAM + (5 * 40)
    .label StartOfScrollingColour = COLOURRAM + (5 * 40)

    RowColumnCollection:
        .for (var row=0; row<20; row++)
        {
            lda StartOfScrollingScreen + (row * 40)
            pha
            lda StartOfScrollingColour + (row * 40)
            pha 

            .for (var col=0; col<39; col++)
            {
                lda StartOfScrollingScreen + (row * 40) + col + 1
                sta StartOfScrollingScreen + (row * 40) + col
                
                lda StartOfScrollingColour + (row * 40) + col + 1
                sta StartOfScrollingColour + (row * 40) + col
            }

            pla
            sta StartOfScrollingColour + (row * 40) + 39
            pla
            sta StartOfScrollingScreen + (row * 40) + 39
        }
        rts
}