path: root/game/addons/zylann.hterrain/hterrain.gd

@tool
extends Node3D

const HT_NativeFactory = preload("./native/factory.gd")
const HT_Mesher = preload("./hterrain_mesher.gd")
const HT_Grid = preload("./util/grid.gd")
const HTerrainData = preload("./hterrain_data.gd")
const HTerrainChunk = preload("./hterrain_chunk.gd")
const HTerrainChunkDebug = preload("./hterrain_chunk_debug.gd")
const HT_Util = preload("./util/util.gd")
const HTerrainCollider = preload("./hterrain_collider.gd")
const HTerrainTextureSet = preload("./hterrain_texture_set.gd")
const HT_Logger = preload("./util/logger.gd")

const SHADER_CLASSIC4 = "Classic4"
const SHADER_CLASSIC4_LITE = "Classic4Lite"
const SHADER_LOW_POLY = "LowPoly"
const SHADER_ARRAY = "Array"
const SHADER_MULTISPLAT16 = "MultiSplat16"
const SHADER_MULTISPLAT16_LITE = "MultiSplat16Lite"
const SHADER_CUSTOM = "Custom"

const MIN_MAP_SCALE = 0.01

# Note, the `str()` syntax is no longer accepted in constants in Godot 4
const _SHADER_TYPE_HINT_STRING = \
   "Classic4," + \
   "Classic4Lite," + \
   "LowPoly," + \
   "Array," + \
   "MultiSplat16," + \
   "MultiSplat16Lite," + \
   "Custom"

# TODO Had to downgrade this to support Godot 3.1.
# Referring to other constants with this syntax isn't working...
#const _SHADER_TYPE_HINT_STRING = str(
#  SHADER_CLASSIC4, ",",
#  SHADER_CLASSIC4_LITE, ",",
#  SHADER_LOW_POLY, ",",
#  SHADER_ARRAY, ",",
#  SHADER_CUSTOM
#)

const _builtin_shaders = {
   SHADER_CLASSIC4: {
      path = "res://addons/zylann.hterrain/shaders/simple4.gdshader",
      global_path = "res://addons/zylann.hterrain/shaders/simple4_global.gdshader"
   },
   SHADER_CLASSIC4_LITE: {
      path = "res://addons/zylann.hterrain/shaders/simple4_lite.gdshader",
      global_path = "res://addons/zylann.hterrain/shaders/simple4_global.gdshader"
   },
   SHADER_LOW_POLY: {
      path = "res://addons/zylann.hterrain/shaders/low_poly.gdshader",
      global_path = "" # Not supported
   },
   SHADER_ARRAY: {
      path = "res://addons/zylann.hterrain/shaders/array.gdshader",
      global_path = "res://addons/zylann.hterrain/shaders/array_global.gdshader"
   },
   SHADER_MULTISPLAT16: {
      path = "res://addons/zylann.hterrain/shaders/multisplat16.gdshader",
      global_path = "res://addons/zylann.hterrain/shaders/multisplat16_global.gdshader"
   },
   SHADER_MULTISPLAT16_LITE: {
      path = "res://addons/zylann.hterrain/shaders/multisplat16_lite.gdshader",
      global_path = "res://addons/zylann.hterrain/shaders/multisplat16_global.gdshader"
   }
}

const _NORMAL_BAKER_PATH = "res://addons/zylann.hterrain/tools/normalmap_baker.gd"
const _LOOKDEV_SHADER_PATH = "res://addons/zylann.hterrain/shaders/lookdev.gdshader"

const SHADER_PARAM_INVERSE_TRANSFORM = "u_terrain_inverse_transform"
const SHADER_PARAM_NORMAL_BASIS = "u_terrain_normal_basis"

const SHADER_PARAM_GROUND_PREFIX = "u_ground_" # + name + _0, _1, _2, _3...

# Those parameters are filtered out in the inspector,
# because they are not supposed to be set through it
const _api_shader_params = {
   "u_terrain_heightmap": true,
   "u_terrain_normalmap": true,
   "u_terrain_colormap": true,
   "u_terrain_splatmap": true,
   "u_terrain_splatmap_1": true,
   "u_terrain_splatmap_2": true,
   "u_terrain_splatmap_3": true,
   "u_terrain_splat_index_map": true,
   "u_terrain_splat_weight_map": true,
   "u_terrain_globalmap": true,

   "u_terrain_inverse_transform": true,
   "u_terrain_normal_basis": true,

   "u_ground_albedo_bump_0": true,
   "u_ground_albedo_bump_1": true,
   "u_ground_albedo_bump_2": true,
   "u_ground_albedo_bump_3": true,

   "u_ground_normal_roughness_0": true,
   "u_ground_normal_roughness_1": true,
   "u_ground_normal_roughness_2": true,
   "u_ground_normal_roughness_3": true,

   "u_ground_albedo_bump_array": true,
   "u_ground_normal_roughness_array": true
}

const _api_shader_ground_albedo_params = {
   "u_ground_albedo_bump_0": true,
   "u_ground_albedo_bump_1": true,
   "u_ground_albedo_bump_2": true,
   "u_ground_albedo_bump_3": true
}

const _ground_texture_array_shader_params = [
   "u_ground_albedo_bump_array",
   "u_ground_normal_roughness_array"
]

const _splatmap_shader_params = [
   "u_terrain_splatmap",
   "u_terrain_splatmap_1",
   "u_terrain_splatmap_2",
   "u_terrain_splatmap_3"
]

const MIN_CHUNK_SIZE = 16
const MAX_CHUNK_SIZE = 64

# Same as HTerrainTextureSet.get_texture_type_name, used for shader parameter names.
# Indexed by HTerrainTextureSet.TYPE_*
const _ground_enum_to_name = [
   "albedo_bump",
   "normal_roughness"
]

const _DEBUG_AABB = false

signal transform_changed(global_transform)

@export_range(0.0, 1.0) var ambient_wind : float:
   get:
      return ambient_wind
   set(amplitude):
      if ambient_wind == amplitude:
         return
      ambient_wind = amplitude
      for layer in _detail_layers:
         layer.update_material()


@export_range(2, 5) var lod_scale := 2.0:
   get:
      return lod_scale
   set(value):
      _lodder.set_split_scale(value)


# Prefer using this instead of scaling the node's transform.
# Node3D.scale isn't used because it's not suitable for terrains,
# it would scale grass too and other environment objects.
# TODO Replace with `size` in world units?
@export var map_scale := Vector3(1, 1, 1):
   get:
      return map_scale
   set(p_map_scale):
      if map_scale == p_map_scale:
         return
      p_map_scale.x = maxf(p_map_scale.x, MIN_MAP_SCALE)
      p_map_scale.y = maxf(p_map_scale.y, MIN_MAP_SCALE)
      p_map_scale.z = maxf(p_map_scale.z, MIN_MAP_SCALE)
      map_scale = p_map_scale
      _on_transform_changed()


@export var centered := false:
   get:
      return centered
   set(p_centered):
      if p_centered == centered:
         return
      centered = p_centered
      _on_transform_changed()


var _custom_shader : Shader = null
var _custom_globalmap_shader : Shader = null
var _shader_type := SHADER_CLASSIC4_LITE
var _shader_uses_texture_array := false
var _material := ShaderMaterial.new()
var _material_params_need_update := false
# Possible values are the same as the enum `GeometryInstance.SHADOW_CASTING_SETTING_*`.
var _cast_shadow_setting := GeometryInstance3D.SHADOW_CASTING_SETTING_ON

var _render_layer_mask := 1

# Actual number of textures supported by the shader currently selected
var _ground_texture_count_cache := 0

var _used_splatmaps_count_cache := 0
var _is_using_indexed_splatmap := false

var _texture_set := HTerrainTextureSet.new()
var _texture_set_migration_textures = null

var _data: HTerrainData = null

var _mesher := HT_Mesher.new()
var _lodder = HT_NativeFactory.get_quad_tree_lod()
var _viewer_pos_world := Vector3()

# [lod][z][x] -> chunk
# This container owns chunks
var _chunks := []
var _chunk_size: int = 32
var _pending_chunk_updates := []

var _detail_layers := []

var _collision_enabled := true
var _collider: HTerrainCollider = null
var _collision_layer := 1
var _collision_mask := 1

# Stats & debug
var _updated_chunks := 0
var _logger = HT_Logger.get_for(self)

# Editor-only
var _normals_baker = null

var _lookdev_enabled := false
var _lookdev_material : ShaderMaterial


func _init():
   _logger.debug("Create HeightMap")
   # This sets up the defaults. They may be overridden shortly after by the scene loader.

   _lodder.set_callbacks(_cb_make_chunk, _cb_recycle_chunk, _cb_get_vertical_bounds)

   set_notify_transform(true)

   # TODO Temporary!
   # This is a workaround for https://github.com/godotengine/godot/issues/24488
   _material.set_shader_parameter("u_ground_uv_scale", 20)
   _material.set_shader_parameter("u_ground_uv_scale_vec4", Color(20, 20, 20, 20))
   _material.set_shader_parameter("u_depth_blending", true)

   _material.shader = load(_builtin_shaders[_shader_type].path)

   _texture_set.changed.connect(_on_texture_set_changed)
   
   if _collision_enabled:
      if _check_heightmap_collider_support():
         _collider = HTerrainCollider.new(self, _collision_layer, _collision_mask)


func _get_property_list():
   # A lot of properties had to be exported like this instead of using `export`,
   # because Godot 3 does not support easy categorization and lacks some hints
   var props = [
      {
         # Terrain data is exposed only as a path in the editor,
         # because it can only be saved if it has a directory selected.
         # That property is not used in scene saving (data is instead).
         "name": "data_directory",
         "type": TYPE_STRING,
         "usage": PROPERTY_USAGE_EDITOR,
         "hint": PROPERTY_HINT_DIR
      },
      {
         # The actual data resource is only exposed for storage.
         # I had to name it so that Godot won't try to assign _data directly
         # instead of using the setter I made...
         "name": "_terrain_data",
         "type": TYPE_OBJECT,
         "usage": PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_RESOURCE_TYPE,
         # This actually triggers `ERROR: Cannot get class`,
         # if it were to be shown in the inspector.
         # See https://github.com/godotengine/godot/pull/41264
         "hint_string": "HTerrainData"
      },
      {
         "name": "chunk_size",
         "type": TYPE_INT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         #"hint": PROPERTY_HINT_ENUM,
         "hint_string": "16, 32"
      },
      {
         "name": "Collision",
         "type": TYPE_NIL,
         "usage": PROPERTY_USAGE_GROUP
      },
      {
         "name": "collision_enabled",
         "type": TYPE_BOOL,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE
      },
      {
         "name": "collision_layer",
         "type": TYPE_INT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_LAYERS_3D_PHYSICS
      },
      {
         "name": "collision_mask",
         "type": TYPE_INT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_LAYERS_3D_PHYSICS
      },
      {
         "name": "Rendering",
         "type": TYPE_NIL,
         "usage": PROPERTY_USAGE_GROUP
      },
      {
         "name": "shader_type",
         "type": TYPE_STRING,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_ENUM,
         "hint_string": _SHADER_TYPE_HINT_STRING
      },
      {
         "name": "custom_shader",
         "type": TYPE_OBJECT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_RESOURCE_TYPE,
         "hint_string": "Shader"
      },
      {
         "name": "custom_globalmap_shader",
         "type": TYPE_OBJECT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_RESOURCE_TYPE,
         "hint_string": "Shader"
      },
      {
         "name": "texture_set",
         "type": TYPE_OBJECT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_RESOURCE_TYPE,
         "hint_string": "Resource"
         # TODO Cannot properly hint the type of the resource in the inspector. 
         # This triggers `ERROR: Cannot get class 'HTerrainTextureSet'`
         # See https://github.com/godotengine/godot/pull/41264
         #"hint_string": "HTerrainTextureSet"
      },
      {
         "name": "render_layers",
         "type": TYPE_INT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_LAYERS_3D_RENDER
      },
      {
         "name": "cast_shadow",
         "type": TYPE_INT,
         "usage": PROPERTY_USAGE_EDITOR | PROPERTY_USAGE_STORAGE,
         "hint": PROPERTY_HINT_ENUM,
         "hint_string": "Off,On,DoubleSided,ShadowsOnly"
      }
   ]

   if _material.shader != null:
      var shader_params := RenderingServer.get_shader_parameter_list(_material.shader.get_rid())
      for p in shader_params:
         if _api_shader_params.has(p.name):
            continue
         var cp := {}
         for k in p:
            cp[k] = p[k]
         cp.name = str("shader_params/", p.name)
         props.append(cp)

   return props


func _get(key: StringName):
   if key == &"data_directory":
      return _get_data_directory()

   if key == &"_terrain_data":
      if _data == null or _data.resource_path == "":
         # Consider null if the data is not set or has no path,
         # because in those cases we can't save the terrain properly
         return null
      else:
         return _data

   if key == &"texture_set":
      return get_texture_set()

   elif key == &"shader_type":
      return get_shader_type()

   elif key == &"custom_shader":
      return get_custom_shader()
   
   elif key == &"custom_globalmap_shader":
      return _custom_globalmap_shader

   elif key.begins_with("shader_params/"):
      var param_name := key.substr(len("shader_params/"))
      return get_shader_param(param_name)

   elif key == &"chunk_size":
      return _chunk_size
   
   elif key == &"collision_enabled":
      return _collision_enabled
   
   elif key == &"collision_layer":
      return _collision_layer

   elif key == &"collision_mask":
      return _collision_mask

   elif key == &"render_layers":
      return get_render_layer_mask()
   
   elif key == &"cast_shadow":
      return _cast_shadow_setting
   

func _set(key: StringName, value):
   if key == &"data_directory":
      _set_data_directory(value)

   # Can't use setget when the exported type is custom,
   # because we were also are forced to use _get_property_list...
   elif key == &"_terrain_data":
      set_data(value)

   elif key == &"texture_set":
      set_texture_set(value)

   # Legacy, left for migration from 1.4
   var key_str := String(key)
   if key_str.begins_with("ground/"):
      for ground_texture_type in HTerrainTextureSet.TYPE_COUNT:
         var type_name = _ground_enum_to_name[ground_texture_type]
         if key_str.begins_with(str("ground/", type_name, "_")):
            var i = key_str.substr(len(key_str) - 1).to_int()
            if _texture_set_migration_textures == null:
               _texture_set_migration_textures = []
            while i >= len(_texture_set_migration_textures):
               _texture_set_migration_textures.append([null, null])
            var texs = _texture_set_migration_textures[i]
            texs[ground_texture_type] = value

   elif key == &"shader_type":
      set_shader_type(value)

   elif key == &"custom_shader":
      set_custom_shader(value)
   
   elif key == &"custom_globalmap_shader":
      _custom_globalmap_shader = value

   elif key.begins_with("shader_params/"):
      var param_name := String(key).substr(len("shader_params/"))
      set_shader_param(param_name, value)

   elif key == &"chunk_size":
      set_chunk_size(value)
      
   elif key == &"collision_enabled":
      set_collision_enabled(value)

   elif key == &"collision_layer":
      _collision_layer = value
      if _collider != null:
         _collider.set_collision_layer(value)

   elif key == &"collision_mask":
      _collision_mask = value
      if _collider != null:
         _collider.set_collision_mask(value)

   elif key == &"render_layers":
      return set_render_layer_mask(value)

   elif key == &"cast_shadow":
      set_cast_shadow(value)


func get_texture_set() -> HTerrainTextureSet:
   return _texture_set


func set_texture_set(new_set: HTerrainTextureSet):
   if _texture_set == new_set:
      return

   if _texture_set != null:
      # TODO This causes `ERROR: Nonexistent signal 'changed' in [Resource:36653]` for some reason
      _texture_set.changed.disconnect(_on_texture_set_changed)

   _texture_set = new_set

   if _texture_set != null:
      _texture_set.changed.connect(_on_texture_set_changed)

   _material_params_need_update = true


func _on_texture_set_changed():
   _material_params_need_update = true
   HT_Util.update_configuration_warning(self, false)


func get_shader_param(param_name: String):
   return _material.get_shader_parameter(param_name)


func set_shader_param(param_name: String, v):
   _material.set_shader_parameter(param_name, v)


func set_render_layer_mask(mask: int):
   _render_layer_mask = mask
   _for_all_chunks(HT_SetRenderLayerMaskAction.new(mask))


func get_render_layer_mask() -> int:
   return _render_layer_mask


func set_cast_shadow(setting: int):
   if setting == _cast_shadow_setting:
      return
   _cast_shadow_setting = setting
   _for_all_chunks(HT_SetCastShadowSettingAction.new(setting))


func get_cast_shadow() -> int:
   return _cast_shadow_setting


func _set_data_directory(dirpath: String):
   if dirpath != _get_data_directory():
      if dirpath == "":
         set_data(null)
      else:
         var fpath := dirpath.path_join(HTerrainData.META_FILENAME)
         if FileAccess.file_exists(fpath):
            # Load existing
            var d = load(fpath)
            set_data(d)
         else:
            # Create new
            var d := HTerrainData.new()
            d.resource_path = fpath
            set_data(d)
   else:
      _logger.warn("Setting twice the same terrain directory??")


func _get_data_directory() -> String:
   if _data != null:
      return _data.resource_path.get_base_dir()
   return ""


func _check_heightmap_collider_support() -> bool:
   return true
   # var v = Engine.get_version_info()
   # if v.major == 3 and v.minor == 0 and v.patch < 4:
   #  _logger.error("Heightmap collision shape not supported in this version of Godot,"
   #     + " please upgrade to 3.0.4 or later")
   #  return false
   # return true


func set_collision_enabled(enabled: bool):
   if _collision_enabled != enabled:
      _collision_enabled = enabled
      if _collision_enabled:
         if _check_heightmap_collider_support():
            _collider = HTerrainCollider.new(self, _collision_layer, _collision_mask)
            # Collision is not updated with data here,
            # because loading is quite a mess at the moment...
            # 1) This function can be called while no data has been set yet
            # 2) I don't want to update the collider more times than necessary
            #    because it's expensive
            # 3) I would prefer not defer that to the moment the terrain is
            #    added to the tree, because it would screw up threaded loading
      else:
         # Despite this object being a Reference,
         # this should free it, as it should be the only reference
         _collider = null


func _for_all_chunks(action):
   for lod in len(_chunks):
      var grid = _chunks[lod]
      for y in len(grid):
         var row = grid[y]
         for x in len(row):
            var chunk = row[x]
            if chunk != null:
               action.exec(chunk)


func get_chunk_size() -> int:
   return _chunk_size


func set_chunk_size(p_cs: int):
   assert(typeof(p_cs) == TYPE_INT)
   _logger.debug(str("Setting chunk size to ", p_cs))
   var cs := HT_Util.next_power_of_two(p_cs)
   if cs < MIN_CHUNK_SIZE:
      cs = MIN_CHUNK_SIZE
   if cs > MAX_CHUNK_SIZE:
      cs = MAX_CHUNK_SIZE
   if p_cs != cs:
      _logger.debug(str("Chunk size snapped to ", cs))
   if cs == _chunk_size:
      return
   _chunk_size = cs
   _reset_ground_chunks()


# Compat
func set_map_scale(p_map_scale: Vector3):
   map_scale = p_map_scale


# Compat
func set_centered(p_centered: bool):
   centered = p_centered


# Gets the global transform to apply to terrain geometry,
# which is different from Node3D.global_transform gives.
# global_transform must only have translation and rotation. Scale support is undefined.
func get_internal_transform() -> Transform3D:
   var gt := global_transform
   var it := Transform3D(gt.basis * Basis().scaled(map_scale), gt.origin)
   if centered and _data != null:
      var half_size := 0.5 * (_data.get_resolution() - 1.0)
      it.origin += it.basis * (-Vector3(half_size, 0, half_size))
   return it


func get_internal_transform_unscaled():
   var gt := global_transform
   if centered and _data != null:
      var half_size := 0.5 * (_data.get_resolution() - 1.0)
      gt.origin += gt.basis * (-Vector3(half_size, 0, half_size))
   return gt


# Converts a world-space position into a map-space position.
# Map space X and Z coordinates correspond to pixel coordinates of the heightmap.
func world_to_map(world_pos: Vector3) -> Vector3:
   return get_internal_transform().affine_inverse() * world_pos


func _notification(what: int):
   match what:
      NOTIFICATION_PREDELETE:
         _logger.debug("Destroy HTerrain")
         # Note: might get rid of a circular ref in GDScript port
         _clear_all_chunks()

      NOTIFICATION_ENTER_WORLD:
         _logger.debug("Enter world")

         if _texture_set_migration_textures != null and _texture_set.get_slots_count() == 0:
            # Convert from 1.4 textures properties to HTerrainTextureSet
            # TODO Unfortunately this might not always work,
            # once again because Godot wants the editor's UndoRedo to have modified the
            # resource for it to be saved... which sucks, sucks, and sucks.
            # I'll never say it enough.
            _texture_set.set_mode(HTerrainTextureSet.MODE_TEXTURES)
            while _texture_set.get_slots_count() < len(_texture_set_migration_textures):
               _texture_set.insert_slot(-1)
            for slot_index in len(_texture_set_migration_textures):
               var texs = _texture_set_migration_textures[slot_index]
               for type in len(texs):
                  _texture_set.set_texture(slot_index, type, texs[type])
            _texture_set_migration_textures = null

         _for_all_chunks(HT_EnterWorldAction.new(get_world_3d()))
         if _collider != null:
            _collider.set_world(get_world_3d())
            _collider.set_transform(get_internal_transform())

      NOTIFICATION_EXIT_WORLD:
         _logger.debug("Exit world")
         _for_all_chunks(HT_ExitWorldAction.new())
         if _collider != null:
            _collider.set_world(null)

      NOTIFICATION_TRANSFORM_CHANGED:
         _on_transform_changed()

      NOTIFICATION_VISIBILITY_CHANGED:
         _logger.debug("Visibility changed")
         _for_all_chunks(HT_VisibilityChangedAction.new(is_visible_in_tree()))


func _on_transform_changed():
   _logger.debug("Transform changed")

   if not is_inside_tree():
      # The transform and other properties can be set by the scene loader,
      # before we enter the tree
      return

   var gt = get_internal_transform()

   _for_all_chunks(HT_TransformChangedAction.new(gt))

   _material_params_need_update = true

   if _collider != null:
      _collider.set_transform(gt)

   transform_changed.emit(gt)


func _enter_tree():
   _logger.debug("Enter tree")

   if Engine.is_editor_hint() and _normals_baker == null:
      _normals_baker = load(_NORMAL_BAKER_PATH).new()
      add_child(_normals_baker)
      _normals_baker.set_terrain_data(_data)

   set_process(true)


func _clear_all_chunks():
   # The lodder has to be cleared because otherwise it will reference dangling pointers
   _lodder.clear()

   #_for_all_chunks(DeleteChunkAction.new())

   for i in len(_chunks):
      _chunks[i].clear()


func _get_chunk_at(pos_x: int, pos_y: int, lod: int) -> HTerrainChunk:
   if lod < len(_chunks):
      return HT_Grid.grid_get_or_default(_chunks[lod], pos_x, pos_y, null)
   return null


func get_data() -> HTerrainData:
   return _data


func has_data() -> bool:
   return _data != null


func set_data(new_data: HTerrainData):
   assert(new_data == null or new_data is HTerrainData)

   _logger.debug(str("Set new data ", new_data))

   if _data == new_data:
      return

   if has_data():
      _logger.debug("Disconnecting old HeightMapData")
      _data.resolution_changed.disconnect(_on_data_resolution_changed)
      _data.region_changed.disconnect(_on_data_region_changed)
      _data.map_changed.disconnect(_on_data_map_changed)
      _data.map_added.disconnect(_on_data_map_added)
      _data.map_removed.disconnect(_on_data_map_removed)

      if _normals_baker != null:
         _normals_baker.set_terrain_data(null)
         _normals_baker.queue_free()
         _normals_baker = null

   _data = new_data

   # Note: the order of these two is important
   _clear_all_chunks()

   if has_data():
      _logger.debug("Connecting new HeightMapData")

      # This is a small UX improvement so that the user sees a default terrain
      if is_inside_tree() and Engine.is_editor_hint():
         if _data.get_resolution() == 0:
            _data._edit_load_default()

      if _collider != null:
         _collider.create_from_terrain_data(_data)

      _data.resolution_changed.connect(_on_data_resolution_changed)
      _data.region_changed.connect(_on_data_region_changed)
      _data.map_changed.connect(_on_data_map_changed)
      _data.map_added.connect(_on_data_map_added)
      _data.map_removed.connect(_on_data_map_removed)

      if _normals_baker != null:
         _normals_baker.set_terrain_data(_data)

      _on_data_resolution_changed()

   _material_params_need_update = true
   
   HT_Util.update_configuration_warning(self, true)
   
   _logger.debug("Set data done")


# The collider might be used in editor for other tools (like snapping to floor),
# so the whole collider can be updated in one go.
# It may be slow for ingame use, so prefer calling it when appropriate.
func update_collider():
   assert(_collision_enabled)
   assert(_collider != null)
   _collider.create_from_terrain_data(_data)


func _on_data_resolution_changed():
   _reset_ground_chunks()


func _reset_ground_chunks():
   if _data == null:
      return

   _clear_all_chunks()

   _pending_chunk_updates.clear()

   _lodder.create_from_sizes(_chunk_size, _data.get_resolution())

   _chunks.resize(_lodder.get_lod_count())

   var cres := _data.get_resolution() / _chunk_size
   var csize_x := cres
   var csize_y := cres

   for lod in _lodder.get_lod_count():
      _logger.debug(str("Create grid for lod ", lod, ", ", csize_x, "x", csize_y))
      var grid = HT_Grid.create_grid(csize_x, csize_y)
      _chunks[lod] = grid
      csize_x /= 2
      csize_y /= 2

   _mesher.configure(_chunk_size, _chunk_size, _lodder.get_lod_count())


func _on_data_region_changed(min_x, min_y, size_x, size_y, channel):
   # Testing only heights because it's the only channel that can impact geometry and LOD
   if channel == HTerrainData.CHANNEL_HEIGHT:
      set_area_dirty(min_x, min_y, size_x, size_y)

      if _normals_baker != null:
         _normals_baker.request_tiles_in_region(Vector2(min_x, min_y), Vector2(size_x, size_y))


func _on_data_map_changed(type: int, index: int):
   if type == HTerrainData.CHANNEL_DETAIL \
   or type == HTerrainData.CHANNEL_HEIGHT \
   or type == HTerrainData.CHANNEL_NORMAL \
   or type == HTerrainData.CHANNEL_GLOBAL_ALBEDO:

      for layer in _detail_layers:
         layer.update_material()

   if type != HTerrainData.CHANNEL_DETAIL:
      _material_params_need_update = true


func _on_data_map_added(type: int, index: int):
   if type == HTerrainData.CHANNEL_DETAIL:
      for layer in _detail_layers:
         # Shift indexes up since one was inserted
         if layer.layer_index >= index:
            layer.layer_index += 1
         layer.update_material()
   else:
      _material_params_need_update = true
   HT_Util.update_configuration_warning(self, true)


func _on_data_map_removed(type: int, index: int):
   if type == HTerrainData.CHANNEL_DETAIL:
      for layer in _detail_layers:
         # Shift indexes down since one was removed
         if layer.layer_index > index:
            layer.layer_index -= 1
         layer.update_material()
   else:
      _material_params_need_update = true
   HT_Util.update_configuration_warning(self, true)


func get_shader_type() -> String:
   return _shader_type


func set_shader_type(type: String):
   if type == _shader_type:
      return
   _shader_type = type
   
   if _shader_type == SHADER_CUSTOM:
      _material.shader = _custom_shader
   else:
      _material.shader = load(_builtin_shaders[_shader_type].path)

   _material_params_need_update = true
   
   if Engine.is_editor_hint():
      notify_property_list_changed()


func get_custom_shader() -> Shader:
   return _custom_shader


func set_custom_shader(shader: Shader):
   if _custom_shader == shader:
      return

   if _custom_shader != null:
      _custom_shader.changed.disconnect(_on_custom_shader_changed)

   if Engine.is_editor_hint() and shader != null and is_inside_tree():
      # When the new shader is empty, allow to fork from the previous shader
      if shader.code.is_empty():
         _logger.debug("Populating custom shader with default code")
         var src := _material.shader
         if src == null:
            src = load(_builtin_shaders[SHADER_CLASSIC4].path)
         shader.code = src.code
         # TODO If code isn't empty,
         # verify existing parameters and issue a warning if important ones are missing

   _custom_shader = shader

   if _shader_type == SHADER_CUSTOM:
      _material.shader = _custom_shader

   if _custom_shader != null:
      _custom_shader.changed.connect(_on_custom_shader_changed)
      if _shader_type == SHADER_CUSTOM:
         _material_params_need_update = true
   
   if Engine.is_editor_hint():
      notify_property_list_changed()


func _on_custom_shader_changed():
   _material_params_need_update = true


func _update_material_params():
   assert(_material != null)
   _logger.debug("Updating terrain material params")
   
   var terrain_textures := {}
   var res := Vector2(-1, -1)
   
   var lookdev_material : ShaderMaterial
   if _lookdev_enabled:
      lookdev_material = _get_lookdev_material()

   # TODO Only get textures the shader supports

   if has_data():
      for map_type in HTerrainData.CHANNEL_COUNT:
         var count := _data.get_map_count(map_type)
         for i in count:
            var param_name: String = HTerrainData.get_map_shader_param_name(map_type, i)
            terrain_textures[param_name] = _data.get_texture(map_type, i)
      res.x = _data.get_resolution()
      res.y = res.x

   # Set all parameters from the terrain system.

   if is_inside_tree():
      var gt := get_internal_transform()
      var t := gt.affine_inverse()
      _material.set_shader_parameter(SHADER_PARAM_INVERSE_TRANSFORM, t)

      # This is needed to properly transform normals if the terrain is scaled
      var normal_basis = gt.basis.inverse().transposed()
      _material.set_shader_parameter(SHADER_PARAM_NORMAL_BASIS, normal_basis)
      
      if lookdev_material != null:
         lookdev_material.set_shader_parameter(SHADER_PARAM_INVERSE_TRANSFORM, t)
         lookdev_material.set_shader_parameter(SHADER_PARAM_NORMAL_BASIS, normal_basis)
   
   for param_name in terrain_textures:
      var tex = terrain_textures[param_name]
      _material.set_shader_parameter(param_name, tex)
      if lookdev_material != null:
         lookdev_material.set_shader_parameter(param_name, tex)

   if _texture_set != null:
      match _texture_set.get_mode():
         HTerrainTextureSet.MODE_TEXTURES:
            var slots_count := _texture_set.get_slots_count()
            for type in HTerrainTextureSet.TYPE_COUNT:
               for slot_index in slots_count:
                  var texture := _texture_set.get_texture(slot_index, type)
                  var shader_param := _get_ground_texture_shader_param_name(type, slot_index)
                  _material.set_shader_parameter(shader_param, texture)

         HTerrainTextureSet.MODE_TEXTURE_ARRAYS:
            for type in HTerrainTextureSet.TYPE_COUNT:
               var texture_array := _texture_set.get_texture_array(type)
               var shader_params := _get_ground_texture_array_shader_param_name(type)
               _material.set_shader_parameter(shader_params, texture_array)

   _shader_uses_texture_array = false
   _is_using_indexed_splatmap = false
   _used_splatmaps_count_cache = 0

   var shader := _material.shader
   if shader != null:
      var param_list := RenderingServer.get_shader_parameter_list(shader.get_rid())
      _ground_texture_count_cache = 0
      for p in param_list:
         if _api_shader_ground_albedo_params.has(p.name):
            _ground_texture_count_cache += 1
         elif p.name == "u_ground_albedo_bump_array":
            _shader_uses_texture_array = true
         elif p.name == "u_terrain_splat_index_map":
            _is_using_indexed_splatmap = true
         elif p.name in _splatmap_shader_params:
            _used_splatmaps_count_cache += 1


# TODO Rename is_shader_using_texture_array()
# Tells if the current shader is using a texture array.
# This will only be valid once the material has been updated internally.
# (for example it won't be valid before the terrain is added to the SceneTree)
func is_using_texture_array() -> bool:
   return _shader_uses_texture_array


# Gets how many splatmaps the current shader is using.
# This will only be valid once the material has been updated internally.
# (for example it won't be valid before the terrain is added to the SceneTree)
func get_used_splatmaps_count() -> int:
   return _used_splatmaps_count_cache


# Tells if the current shader is using a splatmap type based on indexes and weights.
# This will only be valid once the material has been updated internally.
# (for example it won't be valid before the terrain is added to the SceneTree)
func is_using_indexed_splatmap() -> bool:
   return _is_using_indexed_splatmap


static func _get_common_shader_params(shader1: Shader, shader2: Shader) -> Array:
   var shader1_param_names := {}
   var common_params := []
   
   var shader1_params := RenderingServer.get_shader_parameter_list(shader1.get_rid())
   var shader2_params := RenderingServer.get_shader_parameter_list(shader2.get_rid())
   
   for p in shader1_params:
      shader1_param_names[p.name] = true
   
   for p in shader2_params:
      if shader1_param_names.has(p.name):
         common_params.append(p.name)
   
   return common_params


# Helper used for globalmap baking
func setup_globalmap_material(mat: ShaderMaterial):
   mat.shader = get_globalmap_shader()
   if mat.shader == null:
      _logger.error("Could not find a shader to use for baking the global map.")
      return
   # Copy all parameters shaders have in common
   var common_params = _get_common_shader_params(mat.shader, _material.shader)
   for param_name in common_params:
      var v = _material.get_shader_parameter(param_name)
      mat.set_shader_parameter(param_name, v)


# Gets which shader will be used to bake the globalmap
func get_globalmap_shader() -> Shader:
   if _shader_type == SHADER_CUSTOM:
      if _custom_globalmap_shader != null:
         return _custom_globalmap_shader
      _logger.warn("The terrain uses a custom shader but doesn't have one for baking the "
         + "global map. Will attempt to use a built-in shader.")
      if is_using_texture_array():
         return load(_builtin_shaders[SHADER_ARRAY].global_path) as Shader
      return load(_builtin_shaders[SHADER_CLASSIC4].global_path) as Shader
   return load(_builtin_shaders[_shader_type].global_path) as Shader


# Compat
func set_lod_scale(p_lod_scale: float):
   lod_scale = p_lod_scale


# Compat
func get_lod_scale() -> float:
   return lod_scale


func get_lod_count() -> int:
   return _lodder.get_lod_count()


#        3
#      o---o
#    0 |   | 1
#      o---o
#        2
# Directions to go to neighbor chunks
const s_dirs = [
   [-1, 0], # SEAM_LEFT
   [1, 0], # SEAM_RIGHT
   [0, -1], # SEAM_BOTTOM
   [0, 1] # SEAM_TOP
]

#       7   6
#     o---o---o
#   0 |       | 5
#     o       o
#   1 |       | 4
#     o---o---o
#       2   3
#
# Directions to go to neighbor chunks of higher LOD
const s_rdirs = [
   [-1, 0],
   [-1, 1],
   [0, 2],
   [1, 2],
   [2, 1],
   [2, 0],
   [1, -1],
   [0, -1]
]


func _edit_update_viewer_position(camera: Camera3D):
   _update_viewer_position(camera)


func _update_viewer_position(camera: Camera3D):
   if camera == null:
      var viewport := get_viewport()
      if viewport != null:
         camera = viewport.get_camera_3d()
   
   if camera == null:
      return
   
   if camera.projection == Camera3D.PROJECTION_ORTHOGONAL:
      # In this mode, due to the fact Godot does not allow negative near plane,
      # users have to pull the camera node very far away, but it confuses LOD
      # into very low detail, while the seen area remains the same.
      # So we need to base LOD on a different metric.
      var cam_pos := camera.global_transform.origin
      var cam_dir := -camera.global_transform.basis.z
      var max_distance := camera.far * 1.2
      var hit_cell_pos = cell_raycast(cam_pos, cam_dir, max_distance)
      
      if hit_cell_pos != null:
         var cell_to_world := get_internal_transform()
         var h := _data.get_height_at(hit_cell_pos.x, hit_cell_pos.y)
         _viewer_pos_world = cell_to_world * Vector3(hit_cell_pos.x, h, hit_cell_pos.y)
         
   else:
      _viewer_pos_world = camera.global_transform.origin


func _process(delta: float):
   if not Engine.is_editor_hint():
      # In editor, the camera is only accessible from an editor plugin
      _update_viewer_position(null)

   if has_data():
      if _data.is_locked():
         # Can't use the data for now
         return

      if _data.get_resolution() != 0:
         var gt := get_internal_transform()
         # Viewer position such that 1 unit == 1 pixel in the heightmap
         var viewer_pos_heightmap_local := gt.affine_inverse() * _viewer_pos_world
         #var time_before = OS.get_ticks_msec()
         _lodder.update(viewer_pos_heightmap_local)
         #var time_elapsed = OS.get_ticks_msec() - time_before
         #if Engine.get_frames_drawn() % 60 == 0:
         #  _logger.debug(str("Lodder time: ", time_elapsed))

      if _data.get_map_count(HTerrainData.CHANNEL_DETAIL) > 0:
         # Note: the detail system is not affected by map scale,
         # so we have to send viewer position in world space
         for layer in _detail_layers:
            layer.process(delta, _viewer_pos_world)

   _updated_chunks = 0

   # Add more chunk updates for neighboring (seams):
   # This adds updates to higher-LOD chunks around lower-LOD ones,
   # because they might not needed to update by themselves, but the fact a neighbor
   # chunk got joined or split requires them to create or revert seams
   var precount = _pending_chunk_updates.size()
   for i in precount:
      var u: HT_PendingChunkUpdate = _pending_chunk_updates[i]

      # In case the chunk got split
      for d in 4:
         var ncpos_x = u.pos_x + s_dirs[d][0]
         var ncpos_y = u.pos_y + s_dirs[d][1]

         var nchunk := _get_chunk_at(ncpos_x, ncpos_y, u.lod)
         if nchunk != null and nchunk.is_active():
            # Note: this will append elements to the array we are iterating on,
            # but we iterate only on the previous count so it should be fine
            _add_chunk_update(nchunk, ncpos_x, ncpos_y, u.lod)

      # In case the chunk got joined
      if u.lod > 0:
         var cpos_upper_x := u.pos_x * 2
         var cpos_upper_y := u.pos_y * 2
         var nlod := u.lod - 1

         for rd in 8:
            var ncpos_upper_x = cpos_upper_x + s_rdirs[rd][0]
            var ncpos_upper_y = cpos_upper_y + s_rdirs[rd][1]

            var nchunk := _get_chunk_at(ncpos_upper_x, ncpos_upper_y, nlod)
            if nchunk != null and nchunk.is_active():
               _add_chunk_update(nchunk, ncpos_upper_x, ncpos_upper_y, nlod)

   # Update chunks
   var lvisible := is_visible_in_tree()
   for i in len(_pending_chunk_updates):
      var u: HT_PendingChunkUpdate = _pending_chunk_updates[i]
      var chunk := _get_chunk_at(u.pos_x, u.pos_y, u.lod)
      assert(chunk != null)
      _update_chunk(chunk, u.lod, lvisible)
      _updated_chunks += 1

   _pending_chunk_updates.clear()

   if _material_params_need_update:
      _update_material_params()
      HT_Util.update_configuration_warning(self, false)
      _material_params_need_update = false

   # DEBUG
#  if(_updated_chunks > 0):
#     _logger.debug(str("Updated {0} chunks".format(_updated_chunks)))


func _update_chunk(chunk: HTerrainChunk, lod: int, p_visible: bool):
   assert(has_data())

   # Check for my own seams
   var seams := 0
   var cpos_x := chunk.cell_origin_x / (_chunk_size << lod)
   var cpos_y := chunk.cell_origin_y / (_chunk_size << lod)
   var cpos_lower_x := cpos_x / 2
   var cpos_lower_y := cpos_y / 2

   # Check for lower-LOD chunks around me
   for d in 4:
      var ncpos_lower_x = (cpos_x + s_dirs[d][0]) / 2
      var ncpos_lower_y = (cpos_y + s_dirs[d][1]) / 2
      if ncpos_lower_x != cpos_lower_x or ncpos_lower_y != cpos_lower_y:
         var nchunk := _get_chunk_at(ncpos_lower_x, ncpos_lower_y, lod + 1)
         if nchunk != null and nchunk.is_active():
            seams |= (1 << d)

   var mesh := _mesher.get_chunk(lod, seams)
   chunk.set_mesh(mesh)

   # Because chunks are rendered using vertex shader displacement,
   # the renderer cannot rely on the mesh's AABB.
   var s := _chunk_size << lod
   var aabb := _data.get_region_aabb(chunk.cell_origin_x, chunk.cell_origin_y, s, s)
   aabb.position.x = 0
   aabb.position.z = 0
   chunk.set_aabb(aabb)

   chunk.set_visible(p_visible)
   chunk.set_pending_update(false)


func _add_chunk_update(chunk: HTerrainChunk, pos_x: int, pos_y: int, lod: int):
   if chunk.is_pending_update():
      #_logger.debug("Chunk update is already pending!")
      return

   assert(lod < len(_chunks))
   assert(pos_x >= 0)
   assert(pos_y >= 0)
   assert(pos_y < len(_chunks[lod]))
   assert(pos_x < len(_chunks[lod][pos_y]))

   # No update pending for this chunk, create one
   var u := HT_PendingChunkUpdate.new()
   u.pos_x = pos_x
   u.pos_y = pos_y
   u.lod = lod
   _pending_chunk_updates.push_back(u)

   chunk.set_pending_update(true)

   # TODO Neighboring chunks might need an update too
   # because of normals and seams being updated


# Used when editing an existing terrain
func set_area_dirty(origin_in_cells_x: int, origin_in_cells_y: int, \
               size_in_cells_x: int, size_in_cells_y: int):

   var cpos0_x := origin_in_cells_x / _chunk_size
   var cpos0_y := origin_in_cells_y / _chunk_size
   var csize_x := (size_in_cells_x - 1) / _chunk_size + 1
   var csize_y := (size_in_cells_y - 1) / _chunk_size + 1

   # For each lod
   for lod in _lodder.get_lod_count():
      # Get grid and chunk size
      var grid = _chunks[lod]
      var s : int = _lodder.get_lod_factor(lod)

      # Convert rect into this lod's coordinates:
      # Pick min and max (included), divide them, then add 1 to max so it's excluded again
      var min_x := cpos0_x / s
      var min_y := cpos0_y / s
      var max_x := (cpos0_x + csize_x - 1) / s + 1
      var max_y := (cpos0_y + csize_y - 1) / s + 1

      # Find which chunks are within
      for cy in range(min_y, max_y):
         for cx in range(min_x, max_x):
            var chunk = HT_Grid.grid_get_or_default(grid, cx, cy, null)
            if chunk != null and chunk.is_active():
               _add_chunk_update(chunk, cx, cy, lod)


# Called when a chunk is needed to be seen
func _cb_make_chunk(cpos_x: int, cpos_y: int, lod: int):
   # TODO What if cpos is invalid? _get_chunk_at will return NULL but that's still invalid
   var chunk := _get_chunk_at(cpos_x, cpos_y, lod)

   if chunk == null:
      # This is the first time this chunk is required at this lod, generate it
      
      var lod_factor : int = _lodder.get_lod_factor(lod)
      var origin_in_cells_x := cpos_x * _chunk_size * lod_factor
      var origin_in_cells_y := cpos_y * _chunk_size * lod_factor
      
      var material = _material
      if _lookdev_enabled:
         material = _get_lookdev_material()

      if _DEBUG_AABB:
         chunk = HTerrainChunkDebug.new(
            self, origin_in_cells_x, origin_in_cells_y, material)
      else:
         chunk = HTerrainChunk.new(self, origin_in_cells_x, origin_in_cells_y, material)
      chunk.parent_transform_changed(get_internal_transform())

      chunk.set_render_layer_mask(_render_layer_mask)
      chunk.set_cast_shadow_setting(_cast_shadow_setting)

      var grid = _chunks[lod]
      var row = grid[cpos_y]
      row[cpos_x] = chunk

   # Make sure it gets updated
   _add_chunk_update(chunk, cpos_x, cpos_y, lod)

   chunk.set_active(true)
   return chunk


# Called when a chunk is no longer seen
func _cb_recycle_chunk(chunk: HTerrainChunk, cx: int, cy: int, lod: int):
   chunk.set_visible(false)
   chunk.set_active(false)


func _cb_get_vertical_bounds(cpos_x: int, cpos_y: int, lod: int):
   var chunk_size : int = _chunk_size * _lodder.get_lod_factor(lod)
   var origin_in_cells_x := cpos_x * chunk_size
   var origin_in_cells_y := cpos_y * chunk_size
   # This is a hack for speed,
   # because the proper algorithm appears to be too slow for GDScript.
   # It should be good enough for most common cases, unless you have super-sharp cliffs.
   return _data.get_point_aabb(
      origin_in_cells_x + chunk_size / 2, 
      origin_in_cells_y + chunk_size / 2)
#  var aabb = _data.get_region_aabb(
#     origin_in_cells_x, origin_in_cells_y, chunk_size, chunk_size)
#  return Vector2(aabb.position.y, aabb.end.y)


# static func _get_height_or_default(im: Image, pos_x: int, pos_y: int):
#  if pos_x < 0 or pos_y < 0 or pos_x >= im.get_width() or pos_y >= im.get_height():
#     return 0.0
#  return im.get_pixel(pos_x, pos_y).r


# Performs a raycast to the terrain without using the collision engine.
# This is mostly useful in the editor, where the collider can't be updated in realtime.
# Returns cell hit position as Vector2, or null if there was no hit.
# TODO Cannot type hint nullable return value
func cell_raycast(origin_world: Vector3, dir_world: Vector3, max_distance: float):
   assert(typeof(origin_world) == TYPE_VECTOR3)
   assert(typeof(dir_world) == TYPE_VECTOR3)
   if not has_data():
      return null
   # Transform to local (takes map scale into account)
   var to_local := get_internal_transform().affine_inverse()
   var origin = to_local * origin_world
   var dir = to_local.basis * dir_world
   return _data.cell_raycast(origin, dir, max_distance)


static func _get_ground_texture_shader_param_name(ground_texture_type: int, slot: int) -> String:
   assert(typeof(slot) == TYPE_INT and slot >= 0)
   _check_ground_texture_type(ground_texture_type)
   return str(SHADER_PARAM_GROUND_PREFIX, _ground_enum_to_name[ground_texture_type], "_", slot)


# @obsolete
func get_ground_texture(slot: int, type: int) -> Texture:
   _logger.error(
      "HTerrain.get_ground_texture is obsolete, " +
      "use HTerrain.get_texture_set().get_texture(slot, type) instead")
   var shader_param = _get_ground_texture_shader_param_name(type, slot)
   return _material.get_shader_parameter(shader_param)


# @obsolete
func set_ground_texture(slot: int, type: int, tex: Texture):
   _logger.error(
      "HTerrain.set_ground_texture is obsolete, " +
      "use HTerrain.get_texture_set().set_texture(slot, type, texture) instead")
   assert(tex == null or tex is Texture)
   var shader_param := _get_ground_texture_shader_param_name(type, slot)
   _material.set_shader_parameter(shader_param, tex)


func _get_ground_texture_array_shader_param_name(type: int) -> String:
   return _ground_texture_array_shader_params[type] as String


# @obsolete
func get_ground_texture_array(type: int) -> TextureLayered:
   _logger.error(
      "HTerrain.get_ground_texture_array is obsolete, " +
      "use HTerrain.get_texture_set().get_texture_array(type) instead")
   var param_name := _get_ground_texture_array_shader_param_name(type)
   return _material.get_shader_parameter(param_name)


# @obsolete
func set_ground_texture_array(type: int, texture_array: TextureLayered):
   _logger.error(
      "HTerrain.set_ground_texture_array is obsolete, " +
      "use HTerrain.get_texture_set().set_texture_array(type, texarray) instead")
   var param_name := _get_ground_texture_array_shader_param_name(type)
   _material.set_shader_parameter(param_name, texture_array)


func _internal_add_detail_layer(layer):
   assert(_detail_layers.find(layer) == -1)
   _detail_layers.append(layer)


func _internal_remove_detail_layer(layer):
   assert(_detail_layers.find(layer) != -1)
   _detail_layers.erase(layer)


# Returns a list copy of all child HTerrainDetailLayer nodes.
# The order in that list has no relevance.
func get_detail_layers() -> Array:
   return _detail_layers.duplicate()


# @obsolete
func set_detail_texture(slot, tex):
   _logger.error(
      "HTerrain.set_detail_texture is obsolete, use HTerrainDetailLayer.texture instead")


# @obsolete
func get_detail_texture(slot):
   _logger.error(
      "HTerrain.get_detail_texture is obsolete, use HTerrainDetailLayer.texture instead")


# Compat
func set_ambient_wind(amplitude: float):
   ambient_wind = amplitude


static func _check_ground_texture_type(ground_texture_type: int):
   assert(typeof(ground_texture_type) == TYPE_INT)
   assert(ground_texture_type >= 0 and ground_texture_type < HTerrainTextureSet.TYPE_COUNT)


# @obsolete
func get_ground_texture_slot_count() -> int:
   _logger.error("get_ground_texture_slot_count is obsolete, " \
      + "use get_cached_ground_texture_slot_count instead")
   return get_max_ground_texture_slot_count()

# @obsolete
func get_max_ground_texture_slot_count() -> int:
   _logger.error("get_ground_texture_slot_count is obsolete, " \
      + "use get_cached_ground_texture_slot_count instead")
   return get_cached_ground_texture_slot_count()


# This is a cached value based on the actual number of texture parameters
# in the current shader. It won't update immediately when the shader changes,
# only after a frame. This is mostly used in the editor.
func get_cached_ground_texture_slot_count() -> int:
   return _ground_texture_count_cache


func _edit_debug_draw(ci: CanvasItem):
   _lodder.debug_draw_tree(ci)


func _get_configuration_warnings() -> PackedStringArray:
   var warnings := PackedStringArray()

   if _data == null:
      warnings.append("The terrain is missing data.\n" \
         + "Select the `Data Directory` property in the inspector to assign it.")

   if _texture_set == null:
      warnings.append("The terrain does not have a HTerrainTextureSet assigned\n" \
         + "This is required if you want to paint textures on it.")

   else:
      var mode := _texture_set.get_mode()

      if mode == HTerrainTextureSet.MODE_TEXTURES and is_using_texture_array():
         warnings.append("The current shader needs texture arrays,\n" \
            + "but the current HTerrainTextureSet is setup with individual textures.\n" \
            + "You may need to switch it to TEXTURE_ARRAYS mode,\n" \
            + "or re-import images in this mode with the import tool.")

      elif mode == HTerrainTextureSet.MODE_TEXTURE_ARRAYS and not is_using_texture_array():
         warnings.append("The current shader needs individual textures,\n" \
            + "but the current HTerrainTextureSet is setup with texture arrays.\n" \
            + "You may need to switch it to TEXTURES mode,\n" \
            + "or re-import images in this mode with the import tool.")

   # TODO Warn about unused data maps, have a tool to clean them up
   return warnings


func set_lookdev_enabled(enable: bool):
   if _lookdev_enabled == enable:
      return
   _lookdev_enabled = enable
   _material_params_need_update = true
   if _lookdev_enabled:
      _for_all_chunks(HT_SetMaterialAction.new(_get_lookdev_material()))
   else:
      _for_all_chunks(HT_SetMaterialAction.new(_material))


func set_lookdev_shader_param(param_name: String, value):
   var mat = _get_lookdev_material()
   mat.set_shader_parameter(param_name, value)


func is_lookdev_enabled() -> bool:
   return _lookdev_enabled


func _get_lookdev_material() -> ShaderMaterial:
   if _lookdev_material == null:
      _lookdev_material = ShaderMaterial.new()
      _lookdev_material.shader = load(_LOOKDEV_SHADER_PATH)
   return _lookdev_material


class HT_PendingChunkUpdate:
   var pos_x := 0
   var pos_y := 0
   var lod := 0


class HT_EnterWorldAction:
   var world : World3D = null
   func _init(w):
      world = w
   func exec(chunk):
      chunk.enter_world(world)


class HT_ExitWorldAction:
   func exec(chunk):
      chunk.exit_world()


class HT_TransformChangedAction:
   var transform : Transform3D
   func _init(t):
      transform = t
   func exec(chunk):
      chunk.parent_transform_changed(transform)


class HT_VisibilityChangedAction:
   var visible := false
   func _init(v):
      visible = v
   func exec(chunk):
      chunk.set_visible(visible and chunk.is_active())


#class HT_DeleteChunkAction:
#  func exec(chunk):
#     pass


class HT_SetMaterialAction:
   var material : Material = null
   func _init(m):
      material = m
   func exec(chunk):
      chunk.set_material(material)


class HT_SetRenderLayerMaskAction:
   var mask: int = 0
   func _init(m: int):
      mask = m
   func exec(chunk):
      chunk.set_render_layer_mask(mask)


class HT_SetCastShadowSettingAction:
   var setting := 0
   func _init(s: int):
      setting = s
   func exec(chunk):
      chunk.set_cast_shadow_setting(setting)