Scrolling when bunny goes out of center

5 files changed, 105 insertions, 9 deletions

diff --git a/RAM_Var_map b/RAM_Var_map
index fdcdc0f..2399897 100644
--- a/RAM_Var_map
+++ b/RAM_Var_map
@@ -1,6 +1,8 @@
-FF80 = Bunny X position (in px)
-FF81 = Bunny Y position (in px)
+FF80 = Bunny X position (on the screen in px)
+FF81 = Bunny Y position (on the screen in px)
 FF82 = Current Button Direction (Up = 1, Right = 2, Down = 3, Left = 4)
 FF83 = Current Sprite Direction (Moving)
 FF84 = Px step inside of grid (0x00 to 0x0f)
 FF85 = Last Sprite Direction
+FF86 = Bunny X position (in tiles)
+FF87 = Bunny Y position (in tiles)
diff --git a/bunny.gbasm b/bunny.gbasm
index 62ee751..9e80bef 100644
--- a/bunny.gbasm
+++ b/bunny.gbasm
@@ -1,7 +1,7 @@
 Initialize_Bunny:
-	LD A, $20
+	LD A, $50
 	LD ($80), A
-	LD A, $20
+	LD A, $50
 	LD ($81), A
 	RET
 
@@ -27,32 +27,77 @@ Move_Bunny:
 	Move_Bunny.check_direction_end:
 
 	BIT 1, A
-	JR NZ, =Move_Bunny.vertical_move
+	JR NZ, =Move_Bunny.vertical_px_move
 
-	Move_Bunny.horizontal_move:
+	Move_Bunny.horizontal_px_move:
 		LD A, ($81)
 		ADD B
+		CP $30
+		JR C, =Move_Bunny.horizontal_px_move.scrolling_fallback
+		CP $71
+		JR NC, =Move_Bunny.horizontal_px_move.scrolling_fallback
 		LD ($81), A
 		JP =Move_Bunny.check_end_of_movement
+		Move_Bunny.horizontal_px_move.scrolling_fallback:
+			LD A, ($43)
+			ADD B
+			LD ($43), A
+			JP =Move_Bunny.check_end_of_movement
 
-	Move_Bunny.vertical_move:
+
+	Move_Bunny.vertical_px_move:
 		LD A, ($80)
 		ADD B
+		CP $30
+		JR C, =Move_Bunny.vertical_px_move.scrolling_fallback
+		CP $71
+		JR NC, =Move_Bunny.vertical_px_move.scrolling_fallback
 		LD ($80), A
+		JP =Move_Bunny.check_end_of_movement
+		Move_Bunny.vertical_px_move.scrolling_fallback:
+			LD A, ($42)
+			ADD B
+			LD ($42), A
+			JP =Move_Bunny.check_end_of_movement
 
 	Move_Bunny.check_end_of_movement:
+		LD A, ($84)
+		INC A
 		AND $0f
 		LD ($84), A
 		JR NZ, =Move_Bunny.end
 		LD ($83), A
+		LD A, ($85)
+		DEC A
+
+		BIT 1, A
+		JR NZ, =Move_Bunny.vertical_tile_move
+
+		Move_Bunny.horizontal_tile_move:
+			LD A, ($86)
+			ADD B
+			LD ($86), A
+			JP =Move_Bunny.end
+
+		Move_Bunny.vertical_tile_move:
+			LD A, ($87)
+			ADD B
+			LD ($87), A
 
 	Move_Bunny.end:
 	RET
 
 Display_Bunny: ; X position in $81, Y position in $80
+	LD A, ($86)
+	LD HL, $9800
+	CALL =Print_8bit
+
+	LD A, ($87)
+	LD HL, $9820
+	CALL =Print_8bit
+
 	LD A, ($81)
 	LD B, A
-
 	LD A, ($80)
 	LD C, A
 	LD A, ($84)
diff --git a/main.gbasm b/main.gbasm
index 6b701c8..6eb27f3 100644
--- a/main.gbasm
+++ b/main.gbasm
@@ -2,6 +2,7 @@
 
 Entrypoint:
 	CALL =Load_Tile
+	CALL =Load_Number_Font
 	CALL =Initialize_Bunny
 	
 	EI
@@ -16,5 +17,6 @@ VBLANK_Entrypoint:
 	RET
 
 .INCLUDE "tiles.gbasm"
+.INCLUDE "print.gbasm"
 .INCLUDE "bunny.gbasm"
 .INCLUDE "buttons.gbasm"
diff --git a/print.gbasm b/print.gbasm
new file mode 100644
index 0000000..e5bb898
--- /dev/null
+++ b/print.gbasm
@@ -0,0 +1,18 @@
+Print_8bit: ; Number in A, Memory Tilemap position in HL
+	PUSH AF
+	PUSH BC
+
+	LD C, A
+	SWAP A 				   ; We start by the highest nibble
+	AND $0f
+	OR $10
+	LD (HL+), A
+	
+	LD A, C
+	AND $0f 			   ; Then the lowest
+	OR $10
+	LD (HL+), A
+
+	POP BC
+	POP AF
+	RET
diff --git a/tiles.gbasm b/tiles.gbasm
index f69a87d..cd37801 100644
--- a/tiles.gbasm
+++ b/tiles.gbasm
@@ -5,6 +5,24 @@ Tile_Image_Data:
 	.DB $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $c0, $c0
 	.DB $34, $f4, $ce, $3a, $fe, $0a, $fc, $04, $bc, $c4, $5c, $64, $88, $f8, $f0, $f0
 
+Number_Font_Data:
+	.DB $00, $38, $4c, $c6, $c6, $64, $38, $00 ; 0
+	.DB $00, $18, $38, $18, $18, $18, $7e, $00 ; 1
+	.DB $00, $7c, $c6, $0e, $7c, $e0, $fe, $00 ; 2
+	.DB $00, $7e, $0c, $38, $06, $c6, $7c, $00 ; 3
+	.DB $00, $1c, $3c, $6c, $cc, $fe, $0c, $00 ; 4
+	.DB $00, $fc, $80, $fc, $06, $c6, $7c, $00 ; 5
+	.DB $00, $7c, $c0, $fc, $c6, $c6, $7c, $00 ; 6
+	.DB $00, $fe, $c6, $0c, $18, $30, $30, $00 ; 7
+	.DB $00, $7c, $c6, $7c, $c6, $c6, $7c, $00 ; 8
+	.DB $00, $7c, $c6, $c6, $7e, $06, $7c, $00 ; 9
+	.DB $00, $3c, $46, $46, $7e, $46, $46, $00 ; A
+	.DB $00, $7c, $46, $7c, $46, $46, $7c, $00 ; B
+	.DB $00, $3c, $62, $60, $60, $62, $3c, $00 ; C
+	.DB $00, $7c, $62, $62, $62, $62, $7c, $00 ; D
+	.DB $00, $7e, $60, $7c, $60, $60, $7e, $00 ; D
+	.DB $00, $7e, $60, $7c, $60, $60, $60, $00 ; D
+
 Load_Tile:
 	LD HL, $8010
 	LD DE, =Tile_Image_Data
@@ -19,4 +37,15 @@ Load_Tile:
 		JR NZ =Load_Tile.loop0
 	RET
 
-
+Load_Number_Font: ; Load number font into the tilemap at tiles 0x10-0x19
+	LD HL, $8100
+	LD DE, =Number_Font_Data
+	LD B, $80
+	
+	Load_Number_Font.loop:
+		LD A, (DE)
+		LD (HL+), A
+		LD (HL+), A
+		INC DE
+		DEC B
+		JR NZ, =Load_Number_Font.loop