tile-gradient-particles

[gd_scene load_steps=9 format=3 uid="uid://world_start_1218"]

[ext_resource type="Script" path="res://scripts/world.gd" id="1_world"]

[sub_resource type="Gradient" id="Gradient_water"]
offsets = PackedFloat32Array(0, 1)
colors = PackedColorArray(0.1, 0.2, 0.6, 1, 0.3, 0.7, 0.9, 1)

[sub_resource type="GradientTexture1D" id="GradientTexture1D_water"]
gradient = SubResource("Gradient_water")

[sub_resource type="Gradient" id="Gradient_dirt"]
offsets = PackedFloat32Array(0, 1)
colors = PackedColorArray(0.35, 0.22, 0.1, 1, 0.65, 0.5, 0.3, 1)

[sub_resource type="GradientTexture1D" id="GradientTexture1D_dirt"]
gradient = SubResource("Gradient_dirt")

[sub_resource type="Gradient" id="Gradient_grass"]
offsets = PackedFloat32Array(0, 1)
colors = PackedColorArray(0.1, 0.35, 0.05, 1, 0.3, 0.65, 0.1, 1)

[sub_resource type="GradientTexture1D" id="GradientTexture1D_grass"]
gradient = SubResource("Gradient_grass")

[sub_resource type="TileSet" id="TileSet_world"]
custom_data_layer_0/name = "tile_type"
custom_data_layer_0/type = 2

[node name="World" type="Node2D"]
script = ExtResource("1_world")
water_color = SubResource("GradientTexture1D_water")
dirt_color = SubResource("GradientTexture1D_dirt")
grass_color = SubResource("GradientTexture1D_grass")

[node name="TileMap" type="TileMap" parent="."]
tile_set = SubResource("TileSet_world")
format = 2
layer_0/name = "terrain"
layer_0/z_index = -10

extends Node2D
class_name World

enum TILE_TYPES { NONE, WATER, DIRT, GRASS }

@export var water_color: GradientTexture1D
@export var dirt_color: GradientTexture1D
@export var grass_color: GradientTexture1D

@onready var tile_map: TileMap = $TileMap

static var _instance: World = null

var _gradient_map: Dictionary

func _ready():
	if _instance == null:
		_instance = self
	_gradient_map = {
		TILE_TYPES.NONE: null,
		TILE_TYPES.WATER: water_color,
		TILE_TYPES.DIRT: dirt_color,
		TILE_TYPES.GRASS: grass_color,
	}


static func get_tile_data_at(position: Vector2) -> TileData:
	var local_position: Vector2i = _instance.tile_map.local_to_map(position)
	return _instance.tile_map.get_cell_tile_data(0, local_position)


static func get_custom_data_at(position: Vector2, custom_data_name: String) -> Variant:
	var data = get_tile_data_at(position)
	if data == null:
		return null
	return data.get_custom_data(custom_data_name)


static func get_gradient_at(position: Vector2) -> GradientTexture1D:
	var tile_type = get_custom_data_at(position, "tile_type")
	if tile_type == null:
		return null
	return _instance._gradient_map.get(tile_type, null)

[gd_scene load_steps=5 format=3 uid="uid://tank_start_1218"]

[ext_resource type="Script" path="res://scripts/tank.gd" id="1_tank_script"]

[sub_resource type="RectangleShape2D" id="RectangleShape2D_1"]
size = Vector2(26, 26)

[sub_resource type="ParticleProcessMaterial" id="ParticleProcessMaterial_left"]
emission_shape = 3
emission_box_extents = Vector3(10.0, 1.0, 0.0)
direction = Vector3(0.0, -1.0, 0.0)
spread = 30.0
gravity = Vector3(0.0, 0.0, 0.0)
initial_velocity_min = 15.0
initial_velocity_max = 30.0
damping_min = 10.0
damping_max = 20.0
scale_min = 0.3
scale_max = 0.8

[sub_resource type="ParticleProcessMaterial" id="ParticleProcessMaterial_right"]
emission_shape = 3
emission_box_extents = Vector3(10.0, 1.0, 0.0)
direction = Vector3(0.0, 1.0, 0.0)
spread = 30.0
gravity = Vector3(0.0, 0.0, 0.0)
initial_velocity_min = 15.0
initial_velocity_max = 30.0
damping_min = 10.0
damping_max = 20.0
scale_min = 0.3
scale_max = 0.8

[node name="Tank" type="CharacterBody2D"]
script = ExtResource("1_tank_script")

[node name="BodySprite" type="Sprite2D" parent="."]

[node name="CollisionShape2D" type="CollisionShape2D" parent="."]
shape = SubResource("RectangleShape2D_1")

[node name="LeftTrackParticles" type="GPUParticles2D" parent="."]
position = Vector2(0.0, -12.0)
z_index = -5
amount = 16
process_material = SubResource("ParticleProcessMaterial_left")
lifetime = 0.5
emitting = false

[node name="RightTrackParticles" type="GPUParticles2D" parent="."]
position = Vector2(0.0, 12.0)
z_index = -5
amount = 16
process_material = SubResource("ParticleProcessMaterial_right")
lifetime = 0.5
emitting = false

extends CharacterBody2D
class_name Tank

const SPEED = 64.0
const TURN_SPEED = 2.0

var direction := Vector2.RIGHT

@onready var left_track_particles: GPUParticles2D = $LeftTrackParticles
@onready var right_track_particles: GPUParticles2D = $RightTrackParticles
@onready var _left_material: ParticleProcessMaterial = $LeftTrackParticles.process_material
@onready var _right_material: ParticleProcessMaterial = $RightTrackParticles.process_material

var _current_gradient: GradientTexture1D = null

func _physics_process(delta):
	var drive_input := 0.0
	var turn_input := 0.0
	if InputMap.has_action("move_backward") and InputMap.has_action("move_forward"):
		drive_input = Input.get_axis("move_backward", "move_forward")
	if InputMap.has_action("turn_left") and InputMap.has_action("turn_right"):
		turn_input = Input.get_axis("turn_left", "turn_right")
	if turn_input != 0.0:
		direction = direction.rotated(turn_input * (PI / 2.0) * TURN_SPEED * delta)
		rotation = direction.angle()
	if drive_input != 0.0:
		velocity = direction.normalized() * drive_input * SPEED
	else:
		velocity = Vector2.ZERO
	move_and_slide()
	_update_track_particles()


func _update_track_particles() -> void:
	var gradient = World.get_gradient_at(global_position)
	if gradient != _current_gradient:
		_current_gradient = gradient
		_left_material.color_ramp = gradient
		_right_material.color_ramp = gradient
	var is_moving := velocity.length_squared() > 0.0
	left_track_particles.emitting = is_moving
	right_track_particles.emitting = is_moving