ceiling texture, stair/alcove handling

Scripts/Space/SpaceRegion.gd

@@ -6,23 +6,30 @@ extends SpaceEntity
 
 class_name SpaceRegion
 
+# TODO: Make evelation and height be against the parent.
 @export var elevation: float = 0.0
 @export var height: float = 100.0
 @export var wall_texture: Texture2D
 @export var floor_texture: Texture2D
 @export var ceiling_texture: Texture2D
+@export var top_texture: Texture2D
+
+var _is_convex_cache: bool
 
 
 func generate_geometry(space: Space) -> Node3D:
-	return _generate_geometry(space, true)
+	return _generate_geometry(space, true, null)
 
 
 func _process(delta):
 	if Engine.is_editor_hint():
-		self.texture = floor_texture
+		self.texture = top_texture if top_texture else floor_texture
 
 
-func _generate_geometry(space: Space, looked_from_inside: bool) -> Node3D:
+func _generate_geometry(space: Space,
+						looked_from_inside: bool,
+						parent_region: SpaceRegion
+) -> Node3D:
 	var geometry := MeshInstance3D.new()
 	geometry.name = name
 	geometry.position = Vector3(
@@ -32,29 +39,43 @@ func _generate_geometry(space: Space, looked_from_inside: bool) -> Node3D:
 	)
 
 	var mesh := ArrayMesh.new()
-	mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, _generate_wall_arrays(space, looked_from_inside))
+	var surface_count: int = 0
 
+	mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, _generate_wall_arrays(space, looked_from_inside))
+	surface_count += 1
 	var wall_material := StandardMaterial3D.new()
 	wall_material.albedo_texture = wall_texture
-	mesh.surface_set_material(0, wall_material)
+	mesh.surface_set_material(surface_count - 1, wall_material)
 
 	if (looked_from_inside):
 		mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, _generate_floor_arrays(space))
+		surface_count += 1
 		var floor_material := StandardMaterial3D.new()
 		floor_material.albedo_texture = floor_texture
-		mesh.surface_set_material(1, floor_material)
+		mesh.surface_set_material(surface_count - 1, floor_material)
 
 		mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, _generate_ceiling_arrays(space))
+		surface_count += 1
 		var ceiling_material := StandardMaterial3D.new()
 		ceiling_material.albedo_texture = ceiling_texture
 		ceiling_material.cull_mode = BaseMaterial3D.CULL_FRONT # todo: Don't require state change
-		mesh.surface_set_material(2, ceiling_material)
+		mesh.surface_set_material(surface_count - 1, ceiling_material)
+
+	if parent_region and not parent_region._is_convex_cache:
+		if parent_region.height > height:
+			mesh.add_surface_from_arrays(Mesh.PRIMITIVE_TRIANGLES, _generate_ceiling_arrays(space))
+			surface_count += 1
+			var top_material := StandardMaterial3D.new()
+			top_material.albedo_texture = top_texture
+			mesh.surface_set_material(surface_count - 1, top_material)
 
 	geometry.mesh = mesh
 
+	_is_convex_cache = is_convex()
+
 	for child in get_children():
 		if child is SpaceRegion:
-			geometry.add_child(child._generate_geometry(space, not looked_from_inside))
+			geometry.add_child(child._generate_geometry(space, not looked_from_inside, self))
 
 	geometry.create_trimesh_collision()
 	return geometry
@@ -156,3 +177,94 @@ func _generate_ceiling_arrays(space: Space) -> Array:
 	arrays[Mesh.ARRAY_TEX_UV] = uvs
 
 	return arrays
+
+
+## Check whether region polygon forms a convex geometry.
+##
+## Based on: https://math.stackexchange.com/a/1745427
+func is_convex() -> bool:
+	if self.polygon.size() < 3:
+		return false
+
+	var wSign: float = 0        # First nonzero orientation (positive or negative)
+
+	var xSign: float = 0
+	var xFirstSign: float = 0   # Sign of first nonzero edge vector x
+	var xFlips: float = 0       # Number of sign changes in x
+
+	var ySign: float = 0
+	var yFirstSign: float = 0   # Sign of first nonzero edge vector y
+	var yFlips: float = 0       # Number of sign changes in y
+
+	var curr: Vector2 = self.polygon[-2]   # Second-to-last vertex
+	var next: Vector2 = self.polygon[-1]   # Last vertex
+
+	for v in self.polygon:      	 	# Each vertex, in order
+		var prev: Vector2 = curr        # Previous vertex
+		curr = next          			# Current vertex
+		next = v             			# Next vertex
+
+		# Previous edge vector ("before"):
+		var bx: float = curr.x - prev.x
+		var by: float = curr.y - prev.y
+
+		# Next edge vector ("after"):
+		var ax: float = next.x - curr.x
+		var ay: float = next.y - curr.y
+
+		# Calculate sign flips using the next edge vector ("after"),
+		# recording the first sign.
+		if ax > 0:
+			if xSign == 0:
+				xFirstSign = +1
+			elif xSign < 0:
+				xFlips = xFlips + 1
+			xSign = +1
+		elif ax < 0:
+			if xSign == 0:
+				xFirstSign = -1
+			elif xSign > 0:
+				xFlips = xFlips + 1
+			xSign = -1
+
+		if xFlips > 2:
+			return false
+
+		if ay > 0:
+			if ySign == 0:
+				yFirstSign = +1
+			elif ySign < 0:
+				yFlips = yFlips + 1
+			ySign = +1
+		elif ay < 0:
+			if ySign == 0:
+				yFirstSign = -1
+			elif ySign > 0:
+				yFlips = yFlips + 1
+			ySign = -1
+
+		if yFlips > 2:
+			return false
+
+		# Find out the orientation of this pair of edges,
+		# and ensure it does not differ from previous ones.
+		var w := bx * ay - ax * by
+		if (wSign == 0) and (w != 0):
+			wSign = w
+		elif (wSign > 0) and (w < 0):
+			return false
+		elif (wSign < 0) and (w > 0):
+			return false
+
+	# Final/wraparound sign flips:
+	if (xSign != 0) and (xFirstSign != 0) and (xSign != xFirstSign):
+		xFlips = xFlips + 1
+	if (ySign != 0) and (yFirstSign != 0) and (ySign != yFirstSign):
+		yFlips = yFlips + 1
+
+	# Concave polygons have two sign flips along each axis.
+	if (xFlips != 2) or (yFlips != 2):
+		return false
+
+	# This is a convex polygon.
+	return true

Spaces/Dungeon.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=7 format=3 uid="uid://deff7lt34nj0h"]
+[gd_scene load_steps=8 format=3 uid="uid://deff7lt34nj0h"]
 
 [ext_resource type="Script" path="res://Scripts/Space/Space.gd" id="1_ckp7u"]
 [ext_resource type="Script" path="res://Scripts/Space/SpaceRegion.gd" id="2_s3h7s"]
@@ -6,6 +6,7 @@
 [ext_resource type="Texture2D" uid="uid://icmmuqquxhq3" path="res://Art/Stone_06-128x128.png" id="3_ondo6"]
 [ext_resource type="Texture2D" uid="uid://eempmja460l5" path="res://Art/Stone_11-128x128.png" id="4_mnswr"]
 [ext_resource type="Script" path="res://Scripts/Space/SpaceSpawn.gd" id="4_rhl23"]
+[ext_resource type="Texture2D" uid="uid://buoupwtftxjse" path="res://Art/Stone_05-128x128.png" id="5_evp07"]
 
 [node name="Dungeon" type="Node2D"]
 script = ExtResource("1_ckp7u")
@@ -24,10 +25,22 @@ ceiling_texture = ExtResource("4_mnswr")
 
 [node name="Column" type="Polygon2D" parent="Room"]
 texture_repeat = 2
-polygon = PackedVector2Array(8, -40, 48, -64, 88, -24, 64, 0, 24, -8)
+texture = ExtResource("3_ondo6")
+polygon = PackedVector2Array(8, -40, 48, -64, 88, -40, 72, -8, 72, -32, 48, -48, 24, -32, 24, -8)
 uv = PackedVector2Array(1.88, 5.28, 0.6, 1.44, 5.24, 0.64, 5.24, 0.64, 9.94, 3.84, 5.72, 6.56, 5.72, 6.56, 1.88, 5.28, 5.24, 0.64)
 script = ExtResource("2_s3h7s")
 wall_texture = ExtResource("3_ondo6")
+floor_texture = ExtResource("3_ondo6")
+
+[node name="Floor" type="Polygon2D" parent="Room/Column"]
+texture_repeat = 2
+texture = ExtResource("5_evp07")
+polygon = PackedVector2Array(72, -8, 72, -32, 48, -48, 24, -32, 24, -8)
+uv = PackedVector2Array(1.88, 5.28, 0.6, 1.44, 5.24, 0.64, 5.24, 0.64, 9.94, 3.84, 5.72, 6.56, 5.72, 6.56, 1.88, 5.28, 5.24, 0.64)
+script = ExtResource("2_s3h7s")
+height = 20.0
+wall_texture = ExtResource("3_ondo6")
+top_texture = ExtResource("5_evp07")
 
 [node name="Spawn" type="Sprite2D" parent="Room"]
 position = Vector2(-48, 32)