From 487e995ac47811627e9a0324906111a09990230d Mon Sep 17 00:00:00 2001
From: Pawel Lampe <pawel.lampe@gmail.com>
Date: Wed, 24 Jan 2024 21:58:14 +0100
Subject: [PATCH] Improve rebaking, #74

---
 project.godot                     |  1 +
 source/match/TerrainNavigation.gd | 46 +++++++++++++++++++++++++++++--
 2 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/project.godot b/project.godot
index 9fdb71a..a486ae5 100644
--- a/project.godot
+++ b/project.godot
@@ -33,6 +33,7 @@ gdscript/warnings/standalone_expression=0
 gdscript/warnings/incompatible_ternary=0
 gdscript/warnings/static_called_on_instance=0
 gdscript/warnings/assert_always_false=0
+gdscript/warnings/integer_division=0
 
 [display]
 
diff --git a/source/match/TerrainNavigation.gd b/source/match/TerrainNavigation.gd
index 478ceac..4b97ca8 100644
--- a/source/match/TerrainNavigation.gd
+++ b/source/match/TerrainNavigation.gd
@@ -4,6 +4,7 @@ const DOMAIN = Constants.Match.Navigation.Domain.TERRAIN
 
 var _earliest_frame_to_perform_next_rebake = null
 var _is_baking = false
+var _map_geometry = NavigationMeshSourceGeometryData3D.new()
 
 @onready var navigation_map_rid = get_world_3d().navigation_map
 
@@ -20,7 +21,6 @@ func _ready():
 	)
 	NavigationServer3D.map_force_update(navigation_map_rid)
 	MatchSignals.schedule_navigation_rebake.connect(_on_schedule_navigation_rebake)
-	_navigation_region.bake_finished.connect(_on_bake_finished)
 
 
 func _process(_delta):
@@ -31,7 +31,7 @@ func _process(_delta):
 	):
 		_is_baking = true
 		_earliest_frame_to_perform_next_rebake = null
-		_navigation_region.bake_navigation_mesh(true)
+		_rebake()
 
 
 func bake():
@@ -39,7 +39,46 @@ func bake():
 		_navigation_region.navigation_mesh.get_polygon_count() == 0,
 		"bake() should be called exactly once - during runtime"
 	)
-	_navigation_region.bake_navigation_mesh(false)
+	NavigationServer3D.parse_source_geometry_data(
+		_navigation_region.navigation_mesh, _map_geometry, get_tree().root
+	)
+	for node in get_tree().get_nodes_in_group("terrain_navigation_input"):
+		node.remove_from_group("terrain_navigation_input")
+	NavigationServer3D.bake_from_source_geometry_data(
+		_navigation_region.navigation_mesh, _map_geometry
+	)
+	_sync_navmesh_changes()
+
+
+func _rebake():
+	# parse geometry other than map itself
+	var full_geometry = NavigationMeshSourceGeometryData3D.new()
+	NavigationServer3D.parse_source_geometry_data(
+		_navigation_region.navigation_mesh, full_geometry, get_tree().root
+	)
+
+	# add pre-parsed map geometry manually
+	# TODO: get rid of it when NavigationServer3D.parse_source_geometry_data() adds `append` param
+	var new_indices = full_geometry.get_indices()
+	var original_indices_num = new_indices.size()
+	var new_vertices = full_geometry.get_vertices()
+	var original_vertices_num = new_vertices.size()
+	new_indices.append_array(_map_geometry.get_indices())
+	new_vertices.append_array(_map_geometry.get_vertices())
+	for i in range(original_indices_num, new_indices.size()):
+		new_indices[i] += original_vertices_num / 3
+	full_geometry.set_indices(new_indices)
+	full_geometry.set_vertices(new_vertices)
+
+	NavigationServer3D.bake_from_source_geometry_data_async(
+		_navigation_region.navigation_mesh, full_geometry, _on_bake_finished
+	)
+
+
+# TODO: remove whenever Godot fixes that on its side
+func _sync_navmesh_changes():
+	"""this function forces synchronization between server-level primitives and nodes"""
+	_navigation_region.navigation_mesh = _navigation_region.navigation_mesh
 
 
 func _safety_checks():
@@ -74,4 +113,5 @@ func _on_schedule_navigation_rebake(domain):
 
 
 func _on_bake_finished():
+	_sync_navmesh_changes()
 	_is_baking = false