Add entities collisions

6 files changed, 192 insertions, 62 deletions

diff --git a/Makefile b/Makefile
index 002e53b..525d037 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@ build/main.rom: main.gbasm tileset.gbasm
 	gbasm $< $@
 
 run: build/main.rom
-	gb $<
+	gb -s 2 $<
 
 sameboy: build/main.rom
 	sameboy build/main.rom
diff --git a/bunny.gbasm b/bunny.gbasm
index 1386f01..d19b161 100644
--- a/bunny.gbasm
+++ b/bunny.gbasm
@@ -1,5 +1,5 @@
 Initialize_Bunny:
-	LD HL, $mem_entites_list
+	LD HL, $mem_entities_list
 	LD A, $01
 	LD (HL+), A
 
@@ -194,11 +194,11 @@ Fix_Bunny_screen:
 	RET
 
 Move_Bunny:
-	; IF HL IS EVER USED, IT SHOULD BE PUSHED HERE
+	PUSH HL
 	LD C, $00 ; (bit 0 = has_scrolled, bit 1 = has ended movement)
 	LD A, $mem_bunny_direction
 	BIT 3, A
-	JR NZ, =Move_Bunny.check_direction
+	JR NZ, =Move_Bunny.check_collision
 
 	LD A, $mem_button_direction
 	CP $00
@@ -206,6 +206,40 @@ Move_Bunny:
 	SET 3, A
 	LD $mem_bunny_direction, A
 
+	Move_Bunny.check_collision:
+		LD A, $mem_moving_animation_step
+		CP $00
+		JR NZ, =Move_Bunny.check_collision.end
+
+		; THIS ASSUMES THAT THE BUNNY IS ALWAYS THE FIRST ENTITY IN THE LIST
+		LD HL, $mem_entities_list
+		LD A, $mem_bunny_direction
+
+		PUSH BC
+		CALL =Get_Position_After_Move
+		LD A, C
+		CALL =Is_Collisionable
+
+		PUSH AF
+		PUSH HL
+		LD HL, $9ba0
+		CALL =Print_8bit
+		POP HL
+
+		CALL =Carve_Entity_Collision_Map
+		POP AF
+		POP BC
+		CP $00
+		JR Z, =Move_Bunny.check_collision.end
+
+		Move_Bunny.check_collision.collision:
+		LD A, $mem_bunny_direction
+		RES 3, A
+		LD $mem_bunny_direction, A
+		JP =Move_Bunny.end
+
+		Move_Bunny.check_collision.end:
+
 	Move_Bunny.check_direction:
 		LD A, $mem_bunny_direction
 
@@ -218,58 +252,20 @@ Move_Bunny:
 	Move_Bunny.check_direction_end:
 
 	BIT 1, A
-	JR NZ, =Move_Bunny.vertical_move
-
-	Move_Bunny.horizontal_move:
-		Move_Bunny.horizontal_move.check_collision:
-		LD D, B
-		LD A, $mem_bunny_y
-		LD B, A
-		LD A, $mem_bunny_x
+	JR NZ, =Move_Bunny.vertical_viewport_move
 
-		ADD D
-
-		CALL =Is_Solid
-
-		CP $00
-		JR NZ, =Move_Bunny.collision
-
-		LD B, D
-
-	Move_Bunny.horizontal_px_move:
+	Move_Bunny.horizontal_viewport_move:
 		SET 0, C
 		LD A, $reg_viewport_x
 		ADD B
 		LD $reg_viewport_x, A
 		JP =Move_Bunny.check_end_of_movement
 
-	Move_Bunny.vertical_move:
-		Move_Bunny.vertical_move.check_collision:
-		LD D, B
-		LD A, $mem_bunny_y
-		ADD D
-		LD B, A
-		LD A, $mem_bunny_x
-
-		CALL =Is_Solid
-
-		CP $00
-		JR NZ, =Move_Bunny.collision
-
-		LD B, D
-
-	Move_Bunny.vertical_px_move:
+	Move_Bunny.vertical_viewport_move:
 		SET 0, C
 		LD A, $reg_viewport_y
 		ADD B
 		LD $reg_viewport_y, A
-		JP =Move_Bunny.check_end_of_movement
-
-	Move_Bunny.collision:
-		LD A, $mem_bunny_direction
-		RES 3, A
-		LD $mem_bunny_direction, A
-		JP =Move_Bunny.end
 
 	Move_Bunny.check_end_of_movement:
 		LD A, $mem_moving_animation_step
@@ -313,4 +309,5 @@ Move_Bunny:
 	Move_Bunny.end:
 	LD A, C
 	LD $mem_map_loading_flags, A
+	POP HL
 	RET
diff --git a/definitions.gbasm b/definitions.gbasm
index 7342611..d44be40 100644
--- a/definitions.gbasm
+++ b/definitions.gbasm
@@ -45,7 +45,13 @@
 ;	y: u8,
 ; }
 
+; a bit of 1 is equivalent to an entity being on the tile
+.DEFINE mem_entities_collisions $c780 ; Takes the memory from c780 to c7ff
+
+; a bit of 1 is equivalent to the tile being free
 .DEFINE mem_dungeon_map $c800 ; Takes the memory from c800 to c87f
+.DEFINE mem_dungeon_map_high $c8
+
 .DEFINE mem_room_list $c880 ; Takes the memory from c880 to c89f
 .DEFINE mem_number_of_rooms ($c8a0)
 ; struct room {
@@ -64,7 +70,7 @@
 ; 	_padding: u24
 ; }
 
-.DEFINE mem_entites_list $c980 ; Until c9ff
+.DEFINE mem_entities_list $c980 ; Until c9ff
 ; struct entity {
 ;	sprite: u8,
 ;	x: u8,
diff --git a/entities.gbasm b/entities.gbasm
index 3c279be..28df2d8 100644
--- a/entities.gbasm
+++ b/entities.gbasm
@@ -1,7 +1,7 @@
 Prepare_Entities:
 	LD A, $00
 	LD $tmp_var_1, A
-	LD HL, $mem_entites_list
+	LD HL, $mem_entities_list
 	CALL =Prepare_Entity
 	CALL =Prepare_Entity
 	CALL =Prepare_Entity
@@ -39,7 +39,6 @@ Prepare_Entity:
 	LD A, (HL+)
 	LD E, A
 
-
 	CP $00
 	JP Z, =Prepare_Entity.skip
 
@@ -285,7 +284,9 @@ Prepare_Entity:
 	RET
 
 Entities_Behaviours:
-	LD HL, $mem_entites_list
+	CALL =Reset_Entities_Collision_Map
+
+	LD HL, $mem_entities_list
 	CALL =Entity_Behaviour
 	CALL =Entity_Behaviour
 	CALL =Entity_Behaviour
@@ -340,9 +341,49 @@ Entity_Behaviour:
 	LD L, A
 	RET
 
-Entity_collision: ; entity (whatever alignement) in HL, direction to test in A, Result in A
-	PUSH HL
+Carve_Entity_Collision_Map: ; X in C, Y in B
 	PUSH BC
+	PUSH HL
+	PUSH AF
+
+	LD A, C
+	AND $e0
+	JR NZ, =Carve_Entity_Collision_Map.end
+
+	LD A, B
+	AND $e0
+	JR NZ, =Carve_Entity_Collision_Map.end
+
+	LD A, C
+
+	LD H, $00
+	CP $10
+	RL B
+	AND $0f
+	CP $08
+	RL B
+	AND $07
+	LD L, A
+
+	LD A, B
+	LD BC, $mem_entities_collisions
+	OR C
+	LD C, A
+	LD A, (BC)
+
+	OR (HL)
+	LD (BC), A
+
+	Carve_Entity_Collision_Map.end:
+
+	POP AF
+	POP HL
+	POP BC
+	RET
+
+
+Get_Position_After_Move: ; entity (whatever alignement) in HL, direction to test in A, X Result in C, Y result in B
+	PUSH HL
 	PUSH AF
 
 	LD A, L
@@ -357,6 +398,9 @@ Entity_collision: ; entity (whatever alignement) in HL, direction to test in A,
 	LD B, A
 
 	POP AF
+	BIT 3, A
+	JR Z, =Get_Position_After_Move.direction_end
+
 	PUSH BC
 
 	DEC A
@@ -367,24 +411,21 @@ Entity_collision: ; entity (whatever alignement) in HL, direction to test in A,
 	DEC A
 
 	BIT 1, B
-	JR NZ, =Entity_collision.vertical
+	JR NZ, =Get_Position_After_Move.vertical
 
-	Entity_collision.horizontal:
+	Get_Position_After_Move.horizontal:
 		POP BC
 		ADD C
 		LD C, A
-		JR =Entity_collision.direction_end
+		JR =Get_Position_After_Move.direction_end
 
-	Entity_collision.vertical:
+	Get_Position_After_Move.vertical:
 		POP BC
 		ADD B
 		LD B, A
 
-	Entity_collision.direction_end:
-		LD A, C
-		CALL =Is_Solid
+	Get_Position_After_Move.direction_end:
 
-	POP BC
 	POP HL
 	RET
 
@@ -458,7 +499,12 @@ Fox_AI:
 	OR $08
 	LD B, A
 
-	CALL =Entity_collision
+	PUSH BC
+	CALL =Get_Position_After_Move
+	LD A, C
+	CALL =Is_Collisionable
+	CALL =Carve_Entity_Collision_Map
+	POP BC
 	CP $00
 	JR Z, =Fox_AI.change_direction
 
@@ -471,3 +517,84 @@ Fox_AI:
 
 	POP HL
 	RET
+
+Is_Collisionable: ; X in A, Y in B, Result A
+	PUSH BC
+	PUSH HL
+
+	CP $20
+	JR NC, =Is_Collisionable.Solid
+
+	LD C, A
+	LD A, B
+	CP $20
+	JR NC, =Is_Collisionable.Solid
+	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, $mem_dungeon_map_high
+	LD A, (BC)
+	PUSH AF
+	LD A, C
+	LD BC, $mem_entities_collisions
+	OR C
+	LD C, A
+	LD A, (BC)
+	XOR $ff ; 1 in the dungeon map means walkable, 1 in the entity map means unwalkable, we need to invert it.
+	LD B, A
+	POP AF
+	AND B
+
+	AND (HL)
+	CP $01
+	LD A, $00
+	RL A
+
+	POP HL
+	POP BC
+	RET
+
+	Is_Collisionable.Solid:
+	LD A, $01
+	POP HL
+	POP BC
+
+	RET
+
+Reset_Entities_Collision_Map:
+	LD A, $mem_moving_animation_step
+	CP $02
+	JR NZ, =Reset_Entities_Collision_Map.end
+
+	LD HL, $mem_entities_collisions
+	LD BC, $0080
+	CALL =bzero
+
+	LD HL, $mem_entities_list
+	Reset_Entities_Collision_Map.loop:
+		INC L
+		INC L
+		INC L
+
+		LD A, (HL)
+		CALL =Get_Position_After_Move
+		CALL =Carve_Entity_Collision_Map
+
+		LD A, L
+		AND $f8
+		ADD $08
+		LD L, A
+		CP $00
+		JR NZ, =Reset_Entities_Collision_Map.loop
+
+	Reset_Entities_Collision_Map.end:
+	RET
diff --git a/map/generation.gbasm b/map/generation.gbasm
index a08b539..dba1678 100644
--- a/map/generation.gbasm
+++ b/map/generation.gbasm
@@ -22,7 +22,7 @@ Carve_Map: ; X in C, Y in B
 	LD L, A
 
 	LD C, B
-	LD B, $c8
+	LD B, $mem_dungeon_map_high
 	LD A, (BC)
 
 	OR (HL)
diff --git a/map/loading.gbasm b/map/loading.gbasm
index be4c8a4..7c4a0e9 100644
--- a/map/loading.gbasm
+++ b/map/loading.gbasm
@@ -316,7 +316,7 @@ Is_Solid: ; X in A, Y in B, Result A
 	LD L, A
 
 	LD C, B
-	LD B, $c8
+	LD B, $mem_dungeon_map_high
 	LD A, (BC)
 
 	AND (HL)