low stack mode

Author: zohassadar

CHANGELOG.md

@@ -4,6 +4,7 @@
 * Crunch Mode
 * Marathon Mode
 * Hidden Score Mode
+* Low Stack Mode
 * M Score changed to Classic Scoring + Millions counter
 * Invisible linecap turns entire playfield invisible
 * Invisible mode preserves original piece colors

README.md

@@ -25,6 +25,7 @@
     * [Garbage](#garbage)
     * [Drought](#drought)
     * [DAS Delay](#das-delay)
+    * [Low Stack](#low-stack)
     * [Double Killscreen](#double-killscreen)
     * [Invisible](#invisible)
     * [Hard Drop](#hard-drop)
@@ -220,6 +221,12 @@ Create artificially inflated droughts. Increasing the value causes less I pieces
 
 Change the auto-shift delay rate.
 
+### Low Stack
+
+![Low-Stack](./assets/screens/lowstack.png)
+
+Choose a height limit for your stack and stay below or else it's game over.  
+
 ### Double Killscreen
 
 The pieces fall by two blocks every frame. It's hard.

assets/screens/lowstack.png

@@ -34,6 +34,7 @@ BTYPE_START_LINES := $25 ; bcd
 MENU_HIGHLIGHT_COLOR := $12 ; $12 in gym, $16 in original
 BLOCK_TILES := $7B
 EMPTY_TILE := $EF
+LOW_STACK_LINE := $DF
 TETRIMINO_X_HIDE := $EF
 
 PAUSE_SPRITE_X := $74
@@ -70,6 +71,7 @@ MODE_CHECKERBOARD
 MODE_GARBAGE
 MODE_DROUGHT
 MODE_DAS
+MODE_LOWSTACK
 MODE_KILLX2
 MODE_INVISIBLE
 MODE_HARDDROP
@@ -129,6 +131,7 @@ MENU_TOP_MARGIN_SCROLL := 7 ; in blocks
     .byte $4    ; MODE_GARBAGE
     .byte $12   ; MODE_DROUGHT
     .byte $10   ; MODE_DAS
+    .byte $0F   ; MODE_LOWSTACK
     .byte $0    ; MODE_KILLX2
     .byte $0    ; MODE_INVISIBLE
     .byte $0    ; MODE_HARDDROP
@@ -164,6 +167,7 @@ MENU_TOP_MARGIN_SCROLL := 7 ; in blocks
     .byte   "GARBGE"
     .byte   "LOBARS"
     .byte   "DASDLY"
+    .byte   "LOSTAK"
     .byte   "KILLX2"
     .byte   "INVZBL"
     .byte   "HRDDRP"

src/chr/game_tileset.png

@@ -59,11 +59,12 @@ drawTiles(buffer, lookup, `
 #a    GARBAGE                 d#
 #a    DROUGHT                 d#
 #a    DAS DELAY               d#
+#a    LOW STACK               d#
 #a    KILLSCREEN »2           d#
 #a    INVISIBLE               d#
 #a    HARD DROP               d#
-#a    TAP/ROLL SPEED          d#
 `);drawTiles(extra, lookup, `
+#a    TAP/ROLL SPEED          d#
 #a    SCORING                 d#
 #a    HZ DISPLAY              d#
 #a    INPUT DISPLAY           d#
@@ -76,7 +77,6 @@ drawTiles(buffer, lookup, `
 #a    QUAL MODE               d#
 #a    PAL MODE                d#
 #a                            d#
-#a                            d#
 #a V5                         d#
 #a                            d#
 #a                            d#

src/constants.asm

@@ -52,7 +52,11 @@ render_playfield:
         jsr copyPlayfieldRowToVRAM
         jsr copyPlayfieldRowToVRAM
         jsr copyPlayfieldRowToVRAM
-        rts
+        lda practiseType
+        cmp #MODE_LOWSTACK
+        bne @ret
+        jmp copyLowStackRowToVram
+@ret:   rts
 
 vramPlayfieldRows:
         .word   $20CC,$20EC,$210C,$212C
@@ -61,6 +65,22 @@ vramPlayfieldRows:
         .word   $224C,$226C,$228C,$22AC
         .word   $22CC,$22EC,$230C,$232C
 
+copyLowStackRowToVram:
+        lda lowStackRow
+        asl
+        tax
+        lda vramPlayfieldRows+1,x
+        sta PPUADDR
+        lda vramPlayfieldRows,x
+        sta PPUADDR
+        ldx #$0A
+        lda #LOW_STACK_LINE
+@drawLine:
+        sta PPUDATA
+        dex
+        bne @drawLine
+        rts
+
 copyPlayfieldRowToVRAM:
         ldx vramRow
         cpx #$15

src/nametables/game_type_menu.js

@@ -1,7 +1,7 @@
 playState_lockTetrimino:
         jsr isPositionValid
         beq @notGameOver
-; gameOver:
+@gameOver:
         lda outOfDateRenderFlags ; Flag needed to reveal hidden score
         ora #$04
         sta outOfDateRenderFlags
@@ -78,6 +78,25 @@ playState_lockTetrimino:
         inx
         dec generalCounter3
         bne @lockSquare
+        lda practiseType
+        cmp #MODE_LOWSTACK
+        bne @notAboveLowStack
+        jsr checkIfAboveLowStackLine
+        bcc @notAboveLowStack
+        ldx #<lowStackNopeGraphic
+        ldy #>lowStackNopeGraphic
+        lda lowStackRow
+        cmp #$09
+        bcs @drawOnUpperHalf
+; draw on lower half
+        adc #$03 ; carry already clear
+        bne @copyGraphic
+@drawOnUpperHalf:
+        sbc #$04 ; carry already set
+@copyGraphic:
+        jsr copyGraphicToPlayfieldAtCustomRow
+        jmp @gameOver
+@notAboveLowStack:
         lda #$00
         sta lineIndex
         jsr updatePlayfield

src/nmi/render_util.asm

@@ -103,6 +103,8 @@ copyGraphicToPlayfieldAtCustomRow:
         rts
 
 ; $28 is ! in game tileset
+lowStackNopeGraphic:
+        .byte   "N","O","P","E",$FF,$28,$00
 haltEndingGraphic:
         .byte   $FF,"G","G",$FF,$28,$00
 typebSuccessGraphic:

src/playstate/lock.asm

@@ -111,6 +111,22 @@ updateMusicSpeed:
         jsr setMusicTrack
 @ret:   rts
 
+checkIfAboveLowStackLine:
+; carry set - block found
+        ldx lowStackRow
+        lda multBy10Table,x
+        tay
+        ldx #$0A
+        sec
+@checkForBlockInRow:
+        lda playfield,y
+        bpl @foundBlockInRow
+        iny
+        dex
+        bne @checkForBlockInRow
+        clc
+@foundBlockInRow:
+        rts
 
 ; canon is adjustMusicSpeed
 setMusicTrack: