contextual collisions, tilemap support for collision of tiles

nodes/Context.gd

@@ -9,7 +9,7 @@ func local_position_to_context_position(_p_position: Vector2) -> Vector2:
     push_error("Abstract class method is unimplemented")
     return Vector2.ZERO
 
-func is_path_traversible(_p_from: Vector2, _p_to: Vector2) -> bool:
+func is_path_traversible(_p_game_object: Node2D, _p_from: Vector2, _p_to: Vector2) -> bool:
     push_error("Abstract class method is unimplemented")
     return false
 

nodes/GridContext.gd

@@ -9,20 +9,34 @@ export var cell_size: Vector2 = Vector2(64, 64) setget _set_cell_size
 
 signal cell_size_changed(p_old_cell_size, p_new_cell_size)
 
+var _colliders: Dictionary # Node to null (set)
+
 func local_position_to_context_position(p_position: Vector2) -> Vector2:
     return p_position / cell_size
 
-func is_path_traversible(p_from: Vector2, p_to: Vector2) -> bool:
-    # todo:
+func is_path_traversible(p_game_object: Node2D, p_from: Vector2, p_to: Vector2) -> bool:
+    for collider in _colliders:
+        if not collider.is_path_traversible(p_game_object, p_from, p_to):
+            return false
     return true
 
+# todo: Effectful traversal.
 func try_moving(p_game_object: Node2D, p_from: Vector2, p_to: Vector2) -> bool:
-    if not is_path_traversible(p_from, p_to):
+    if not is_path_traversible(p_game_object, p_from, p_to):
         return false
-    
+
     p_game_object.position = cell_size * p_to
     return true
 
+func register_collider(p_collider: Node) -> void:
+    _colliders[p_collider] = null
+    if p_collider.connect("child_exiting_tree", self, "_on_collider_exiting_tree") != OK:
+        assert(false)
+
+func _on_collider_exiting_tree(p_collider) -> void:
+    if not _colliders.erase(p_collider):
+        pass
+
 func _set_cell_size(p_new_cell_size: Vector2) -> void:
     if p_new_cell_size.x == 0 or p_new_cell_size.y == 0:
         push_error("Cell size cannot be zero")

nodes/TileMapObject.gd

@@ -7,6 +7,7 @@ extends TileMap
 export var expose_collisions: bool = true
 
 var _descriptor_name_to_id: Dictionary # String to int
+var _id_to_descriptor_name: Dictionary # int to String
 
 func change_tile_texture(p_tile: String, p_texture: Texture) -> void:
     if not p_tile in _descriptor_name_to_id:
@@ -16,8 +17,19 @@ func change_tile_texture(p_tile: String, p_texture: Texture) -> void:
     var id := _descriptor_name_to_id[p_tile] as int
     tile_set.tile_set_texture(id, p_texture)
 
+func is_path_traversible(p_game_object: Node2D, p_from: Vector2, p_to: Vector2) -> bool:
+    if p_from.distance_squared_to(p_to) == 1:
+        var id := get_cell(int(p_to.x), int(p_to.y))
+        if id == -1: return true
+        var descriptor = _id_to_descriptor_name[id] as String
+        return get_node(descriptor).is_traversible_for(p_game_object)
+    else:
+        print_debug("Unimplemented")
+        return false
+
 func _enter_tree() -> void:
     tile_set = TileSet.new()
+    get_parent().register_collider(self)
 
     # It's okay to fail here for non-grid contexts.
     if get_parent().connect("cell_size_changed", self, "_update_cell_size"):
@@ -41,6 +53,7 @@ func _update_cell_size(_p_old_cell_size: Vector2, p_new_cell_size: Vector2) -> v
 func _on_child_entered_tree(p_node: Node) -> void:
     var id := tile_set.get_last_unused_tile_id()
     _descriptor_name_to_id[p_node.name] = id
+    _id_to_descriptor_name[id] = p_node.name
     tile_set.create_tile(id)
     tile_set.tile_set_texture(id, p_node.texture)
 
@@ -51,3 +64,5 @@ func _on_child_exiting_tree(p_node: Node) -> void:
     tile_set.remove_tile(id)
     if not _descriptor_name_to_id.erase(p_node.name):
         assert(false)
+    if not _id_to_descriptor_name.erase(id):
+        assert(false)

nodes/TileMapTileDescriptor.gd

@@ -7,6 +7,9 @@ export var texture: Texture setget _set_texture
 # todo: More layer customizeability.
 export var is_solid: bool
 
+func is_traversible_for(_p_game_object: Node2D) -> bool:
+    return not is_solid
+
 func _set_texture(p_texture: Texture) -> void:
     texture = p_texture
     if is_inside_tree():

scenes/Game.tscn

@@ -40,10 +40,10 @@ script = ExtResource( 7 )
 
 [node name="Brickwall" parent="GridContext/TileMapObject" instance=ExtResource( 8 )]
 
-[node name="GameObject" parent="GridContext" instance=ExtResource( 5 )]
+[node name="Player" parent="GridContext" instance=ExtResource( 5 )]
 position = Vector2( 384, 128 )
 
-[node name="Visual" type="Sprite" parent="GridContext/GameObject"]
+[node name="Visual" type="Sprite" parent="GridContext/Player"]
 scale = Vector2( 4, 4 )
 texture = ExtResource( 2 )
 centered = false
@@ -53,9 +53,9 @@ __meta__ = {
 }
 target_size = Vector2( 64, 64 )
 
-[node name="4WayController" parent="GridContext/GameObject" instance=ExtResource( 3 )]
+[node name="4WayController" parent="GridContext/Player" instance=ExtResource( 3 )]
 
-[node name="Camera2D" type="Camera2D" parent="GridContext/GameObject"]
+[node name="Camera2D" type="Camera2D" parent="GridContext/Player"]
 position = Vector2( 32, 32 )
 __meta__ = {
 "_edit_lock_": true