TouhouGD/script/manager/camera_manager.gd

extends Camera3D
class_name CameraManager

@export var global_effect_curve: Curve

var target: int
var target_character_pos: Vector2      = Vector2.ZERO
var target_pos: Vector2                = Vector2.ZERO
var target_pos_y: float
var target_pos_now: Vector2            = Vector2.ZERO
var level_size: Vector2                = Vector2(12.8, 7.68)
var level_pos: Vector2                 = Vector2.ZERO
var offset: float                      = 10
var shake_offset_x: float
var camera_limit: Vector3              = Vector3(6.4, 1.7, 3.58) #x,z-up,z-down
var camera_size: float                 = 7.2
var basic_size: Vector2                = Vector2(640, 360)
var scale_y: float                     = cos(deg_to_rad(45.0)) * 2.0 #1.414
var sample_rate: float                 = 3.6
var stage_size: Vector2                = basic_size * sample_rate
var stage_scale: Vector2               = Vector2(1, scale_y) / sample_rate
var stage_offset_y: float              = (scale_y - 1.0) * 0.5 / sample_rate * stage_size.y
var screen_pos_scale: Vector2          = Vector2(sample_rate, sample_rate/scale_y)
var screen_pos_offset: Vector2         = Vector2(0, -stage_offset_y)
var global_effect_list: Array[Variant] = []


class GlobalEffect:
	var effect_type: Enum.EGlobalEffect
	var life_time: float
	var life_time_now: float
	var value: float


func _ready():
	Global.camera_mgr = self
	SignalManager.character_create.connect(on_character_create)
	SignalManager.character_pos_changed.connect(on_character_pos_changed)
	SignalManager.character_destroy.connect(on_character_destroy)
	SignalManager.level_size_change.connect(on_level_size_change)
	SignalManager.level_pos_change.connect(on_level_pos_change)
	SignalManager.level_loading_end.connect(on_level_loading_end)


func _process(delta):
	update_global_effect(delta)
	update_camera_pos(delta)


func update_global_effect(delta):
	var remove_list: Array[Variant] = []
	for global_effect: GlobalEffect in global_effect_list:
		global_effect.life_time_now += delta
		global_effect.life_time_now = min(global_effect.life_time_now, global_effect.life_time)
		if global_effect.life_time_now == global_effect.life_time:
			remove_list.append(global_effect)
		var rate: float  = global_effect.life_time_now/global_effect.life_time
		var value: float = global_effect_curve.sample(rate)*global_effect.value
		match global_effect.effect_type:
			Enum.EGlobalEffect.CameraSize:
				size = camera_size * (1 - value)
				refresh_target_pos()
			Enum.EGlobalEffect.CameraShake:
				shake_offset_x = (sin(rate * PI * 10) - 0.5)*0.04*value
			Enum.EGlobalEffect.ColorShift:
				Global.view_mgr.set_post_processing("shift_strength", value)
			Enum.EGlobalEffect.Blur:
				Global.view_mgr.set_post_processing("blur_strength", value)
			Enum.EGlobalEffect.SpeedLine:
				Global.view_mgr.set_post_processing("speed_line_strength", value)
			_: pass
	for global_effect: GlobalEffect in remove_list:
		global_effect_list.erase(global_effect)


func update_camera_pos(delta):
	target_pos_lerp(0, delta, 6)
	target_pos_lerp(1, delta, 6)
	position.x = (target_pos_now.x + shake_offset_x)
	position.z = (target_pos_now.y + target_pos_y + offset)
	position.y = (target_pos_y + offset)


func target_pos_lerp(index: int, delta: float, delta_scale: float):
	var target_pos_real: Vector2 = target_pos
	var diff                     = abs(target_pos_now[index] - target_pos_real[index])
	if diff < Setting.pixel_size:
		target_pos_now[index] = target_pos_real[index]
	else:
		var weight_min = Setting.pixel_size / 2 / diff
		var weight     = max(delta * delta_scale, weight_min)
		target_pos_now[index] = lerp(target_pos_now[index], target_pos_real[index], weight)


func on_character_create(id: int, type: int, pos: Vector3):
	if type == Enum.ECharacterType.Player:
		target = id
		on_character_pos_changed(id, pos)
		on_level_loading_end()


func on_character_pos_changed(id: int, pos: Vector3):
	if id == target:
		target_character_pos.x = pos.x
		target_character_pos.y = pos.z
		target_pos_y = pos.y
		refresh_target_pos()


func on_character_destroy(id: int): target = 0


func refresh_target_pos():
	var pos: Vector2            = target_character_pos
	var camera_size_diff: float = (camera_size - size)/2.0
	var x_min: float            = level_pos.x + camera_limit.x - camera_size_diff
	var x_max: float            = level_pos.x + level_size.x - camera_limit.x + camera_size_diff
	var y_min: float            = level_pos.y + camera_limit.y - target_pos_y - camera_size_diff
	var y_max: float            = level_pos.y + level_size.y - camera_limit.z - target_pos_y + camera_size_diff
	target_pos.x = Util.snap_float(clamp(pos.x, x_min, x_max))
	target_pos.y = Util.snap_float(clamp(pos.y-target_pos_y, y_min, y_max))


func on_level_size_change(size: Vector2): level_size = size


func on_level_pos_change(pos: Vector2): level_pos = pos


func on_level_loading_end():
	target_pos_now.x = target_pos.x
	target_pos_now.y = target_pos.y


func get_screen_pos(pos: Vector3) -> Vector2:
	var ret: Vector2 = unproject_position(pos)
	ret.x /= screen_pos_scale.x
	ret.y /= screen_pos_scale.y
	ret.x += screen_pos_offset.x
	ret.y += screen_pos_offset.y
	return ret


func add_global_effect(effect_type: Enum.EGlobalEffect, life_time: float, value: float) -> void:
	value *= 0.5
	for global_effect: GlobalEffect in global_effect_list:
		if global_effect.effect_type == effect_type:
			global_effect.life_time = life_time
			global_effect.life_time_now = 0
			global_effect.value = value
			return
	var global_effect = GlobalEffect.new()
	global_effect.effect_type = effect_type
	global_effect.life_time = life_time
	global_effect.life_time_now = 0
	global_effect.value = value
	global_effect_list.append(global_effect)
	return


func effect(pause_time) -> void:
	if not pause_time:
		return
	var basic_pause_time: float = 0.3
	var effect_time             = pause_time * 2
	var rate                    = pause_time/basic_pause_time
	add_global_effect(Enum.EGlobalEffect.CameraShake, effect_time, 0.8 * rate)
	add_global_effect(Enum.EGlobalEffect.CameraSize, effect_time, 0.1 * rate)
	add_global_effect(Enum.EGlobalEffect.ColorShift, effect_time, 0.8 * rate)
	add_global_effect(Enum.EGlobalEffect.Blur, effect_time, 0.8 * rate)
	#add_global_effect(Enum.EGlobalEffect.SpeedLine,effect_time,0.2* rate)
	return


func effect_shake(pause_time) -> void:
	if not pause_time:
		return
	var basic_pause_time: float = 0.3
	var effect_time             = pause_time * 2
	var rate                    = pause_time/basic_pause_time
	add_global_effect(Enum.EGlobalEffect.CameraShake, effect_time, 0.8 * rate)
	return