Generate a single tunnel in dungeon generation

7 files changed, 188 insertions, 50 deletions

diff --git a/definitions.gbasm b/definitions.gbasm
index f6b757e..2df133f 100644
--- a/definitions.gbasm
+++ b/definitions.gbasm
@@ -10,6 +10,9 @@
 .DEFINE VRAM_start $8000
 .DEFINE OAM_start $FE00
 
+.DEFINE dungeon_generation_step $20
+.DEFINE intial_duplication_probablity $2
+
 .DEFINE mem_bunny_x_px ($c000)
 .DEFINE mem_bunny_y_px ($c001)
 .DEFINE mem_button_direction ($c002)
@@ -23,6 +26,13 @@
 .DEFINE mem_rng_state_1 ($c00a) ; 2 bytes
 .DEFINE mem_rng_state_2 ($c00b) ; 2 bytes
 
+.DEFINE mem_dungeon_generation_heads $c700 ; Takes the memory from c700 to c717
+; struct head {
+; 	direction: u8 (really u3 but padding),
+; 	x: u8,
+;	y: u8,
+; }
+
 .DEFINE mem_dungeon_map $c800 ; Takes the memory from c800 to c87f
 
 .DEFINE enum_direction_left $01
diff --git a/init.gbasm b/init.gbasm
index 8483d4a..ac9b67b 100644
--- a/init.gbasm
+++ b/init.gbasm
@@ -41,12 +41,12 @@ Wait_VBlank:
 	LD $reg_lcd_controller, A
 
 Empty_VRAM: ; (Clear screen)
-	LD hl, $VRAM_start ; We set the HL register to the start of VRAM
+	LD HL, $VRAM_start ; We set the HL register to the start of VRAM
 	Empty_VRAM.loop:
 		XOR A
-		LD (HL+), a 						; We set the memory pointed to by HL to 0 and increase HL
-		LD a, $a0
-		CP h        						; Until h has reached $a0 ($a0000 is the end of VRAM)
+		LD (HL+), A 						; We set the memory pointed to by HL to 0 and increase HL
+		LD A, $a0
+		CP H        						; Until h has reached $a0 ($a0000 is the end of VRAM)
 		JR NZ, =Empty_VRAM.loop
 
 	; BG Palette
diff --git a/main.gbasm b/main.gbasm
index a315d48..3dc2427 100644
--- a/main.gbasm
+++ b/main.gbasm
@@ -2,11 +2,11 @@
 .INCLUDE "init.gbasm"
 
 Entrypoint:
-	CALL =Initialize_Dungeon
+	CALL =Initialize_RNG
+	CALL =Dungeon_Generation
 	CALL =Initialize_Bunny
 	CALL =Load_Tile
 	CALL =Load_Map
-	CALL =Initialize_RNG
 
 	; LCDC
 	LD A, $87
@@ -21,11 +21,11 @@ VBLANK_Entrypoint:
 	CALL =Pad_Button_Check
 	CALL =Move_Bunny
 	CALL =Display_Bunny
-	CALL =RNG_Step
 	RET
 
 .INCLUDE "tiles.gbasm"
-.INCLUDE "map.gbasm"
+.INCLUDE "map/loading.gbasm"
+.INCLUDE "map/generation.gbasm"
 .INCLUDE "bunny.gbasm"
 .INCLUDE "buttons.gbasm"
 .INCLUDE "rng.gbasm"
diff --git a/map/generation.gbasm b/map/generation.gbasm
new file mode 100644
index 0000000..1bedffc
--- /dev/null
+++ b/map/generation.gbasm
@@ -0,0 +1,168 @@
+Initial_dungeon:
+	.DB $00, $00, $00, $00,
+	.DB $00, $00, $00, $00,
+	.DB $00, $00, $00, $00,
+	.DB $00, $00, $00, $00,
+	.DB $00, $00, $00, $00,
+	.DB $00, $00, $00, $00,
+	.DB $00, $00, $00, $00,
+	.DB $03, $e0, $00, $00,
+	.DB $02, $20, $00, $00,
+	.DB $02, $20, $00, $00,
+	.DB $02, $20, $00, $00,
+	.DB $02, $20, $00, $00,
+	.DB $02, $20, $00, $00,
+	.DB $0e, $20, $00, $00,
+	.DB $3f, $20, $00, $00,
+	.DB $3f, $20, $00, $00,
+	.DB $3f, $3f, $80, $00,
+	.DB $3f, $00, $80, $00,
+	.DB $3f, $00, $80, $00,
+	.DB $3f, $00, $80, $00,
+	.DB $3f, $00, $80, $00,
+	.DB $3f, $00, $80, $00,
+	.DB $00, $01, $f8, $00,
+	.DB $00, $01, $f8, $00,
+	.DB $00, $01, $f8, $00,
+	.DB $00, $01, $f8, $00,
+	.DB $00, $01, $f8, $00,
+	.DB $00, $01, $ff, $80,
+	.DB $00, $01, $f8, $80,
+	.DB $00, $01, $f8, $80,
+	.DB $00, $00, $ff, $80,
+	.DB $00, $00, $00, $00,
+
+Initialize_Dungeon:
+	LD HL, $mem_dungeon_map
+	LD DE, =Initial_dungeon
+	LD BC, $0100
+	JP =memcpy
+
+Carve_Tunnel: ; X in A, Y in B
+	PUSH BC
+	PUSH HL
+	LD A, C
+
+	LD H, $00
+	CP $10
+	RL B
+	AND $0f
+	CP $08
+	RL B
+	AND $07
+	LD L, A
+
+	LD C, B
+	LD B, $c8
+	LD A, (BC)
+
+	OR (HL)
+	LD (BC), A
+
+	POP HL
+	POP BC
+ 	RET
+
+Dungeon_Generation:
+	; Head initialization
+	LD HL, $mem_dungeon_generation_heads
+	CALL =RNG_Step
+	AND $03
+	ADD $01
+	LD (HL+), A
+	LD A, $10
+	LD (HL+), A
+	LD (HL+), A
+
+	LD A, $20
+	PUSH AF
+
+	Dungeon_Generation.Step:
+		LD HL, $mem_dungeon_generation_heads
+
+		Dungeon_Generation.Head_loop:
+			LD B, (HL)
+			LD A, B
+
+			CP $00
+			JR Z, =Dungeon_Generation.Head_loop.end
+
+			CALL =RNG_Step
+			AND $07
+			JR NZ, =Dungeon_Generation.Direction_Change.end
+			Dungeon_Generation.Direction_Change:
+				DEC B
+				CALL =RNG_Step
+				AND $01
+				XOR B
+				XOR $02
+				INC A
+				LD B, A
+				LD (HL), B
+			Dungeon_Generation.Direction_Change.end:
+
+			INC HL
+
+			LD C, (HL)
+			LD A, B
+
+			CP $01
+			JR NZ =Dungeon_Generation.Left.end
+			Dungeon_Generation.Left:
+				DEC C
+			Dungeon_Generation.Left.end:
+
+			CP $02
+			JR NZ =Dungeon_Generation.Right.end
+			Dungeon_Generation.Right:
+				INC C
+			Dungeon_Generation.Right.end:
+			
+			AND $e0
+
+			JR NZ, =Dungeon_Generation.DonT_Update_X
+			LD (HL), C
+			Dungeon_Generation.DonT_Update_X:
+
+			INC HL
+
+			LD C, (HL)
+			LD A, B
+
+			CP $03
+			JR NZ =Dungeon_Generation.Up.end
+			Dungeon_Generation.Up:
+				DEC C
+			Dungeon_Generation.Up.end:
+
+			CP $04
+			JR NZ =Dungeon_Generation.Down.end
+			Dungeon_Generation.Down:
+				INC C
+			Dungeon_Generation.Down.end:
+			
+			AND $e0
+
+			JR NZ, =Dungeon_Generation.DonT_Update_Y
+			LD (HL), C
+			Dungeon_Generation.DonT_Update_Y:
+
+			DEC HL 
+			LD A, (HL+)
+			LD C, A
+			LD A, (HL+)
+			LD B, A
+			LD A, C
+			CALL =Carve_Tunnel
+			JP =Dungeon_Generation.Head_loop
+
+		Dungeon_Generation.Head_loop.end:
+
+		POP AF
+		DEC A
+		PUSH AF
+		CP $00
+		JR NZ, =Dungeon_Generation.Step
+
+	POP AF
+	RET
diff --git a/map.gbasm b/map/loading.gbasm
index d664203..8b3f414 100644
--- a/map.gbasm
+++ b/map/loading.gbasm
@@ -236,47 +236,6 @@ Load_Block: ; X in A, Y in B
 	POP BC
 	RET
 
-Initial_dungeon:
-	.DB $00, $00, $00, $00,
-	.DB $00, $00, $00, $00,
-	.DB $00, $00, $00, $00,
-	.DB $00, $00, $00, $00,
-	.DB $00, $00, $00, $00,
-	.DB $00, $00, $00, $00,
-	.DB $00, $00, $00, $00,
-	.DB $03, $e0, $00, $00,
-	.DB $02, $20, $00, $00,
-	.DB $02, $20, $00, $00,
-	.DB $02, $20, $00, $00,
-	.DB $02, $20, $00, $00,
-	.DB $02, $20, $00, $00,
-	.DB $0e, $20, $00, $00,
-	.DB $3f, $20, $00, $00,
-	.DB $3f, $20, $00, $00,
-	.DB $3f, $3f, $80, $00,
-	.DB $3f, $00, $80, $00,
-	.DB $3f, $00, $80, $00,
-	.DB $3f, $00, $80, $00,
-	.DB $3f, $00, $80, $00,
-	.DB $3f, $00, $80, $00,
-	.DB $00, $01, $f8, $00,
-	.DB $00, $01, $f8, $00,
-	.DB $00, $01, $f8, $00,
-	.DB $00, $01, $f8, $00,
-	.DB $00, $01, $f8, $00,
-	.DB $00, $01, $ff, $80,
-	.DB $00, $01, $f8, $80,
-	.DB $00, $01, $f8, $80,
-	.DB $00, $00, $ff, $80,
-	.DB $00, $00, $00, $00,
-
-Initialize_Dungeon:
-	LD HL, $mem_dungeon_map
-	LD DE, =Initial_dungeon
-	LD BC, $0100
-	JP =memcpy
-
-
 Is_Solid: ; X in A, Y in B, Result A
 	PUSH BC
 
diff --git a/rng.gbasm b/rng.gbasm
index 8649024..f639946 100644
--- a/rng.gbasm
+++ b/rng.gbasm
@@ -9,7 +9,7 @@ Debug_RNG:
 Initialize_RNG:
 	LD A, $42
 	LD $mem_rng_state_1, A
-	LD A, $69
+	LD A, $15
 	LD $mem_rng_state_2, A
 	RET
 
diff --git a/tiles.gbasm b/tiles.gbasm
index b66222c..faeda8d 100644
--- a/tiles.gbasm
+++ b/tiles.gbasm
@@ -127,3 +127,4 @@ Load_Number_Font: ; Load number font into the tilemap at tiles 0x10-0x1f
 		INC DE
 		DEC B
 		JR NZ, =Load_Number_Font.loop
+	RET