看向目标
八个锥体对同一个移动的球体调用 look_at。每帧一次调用就替代了全部三角函数。
上方的编辑器正在运行这个项目。改一行代码,它就会重新加载。
用到的 Godot 类
Node3DMeshInstance3DOmniLight3D
代码
scripts/main.gd
extends Node
const POINTERS: int = 8
const RING: float = 6.0
const ROAM: float = 2.2
var pointers: Array[Node3D] = []
var target: Node3D
var elapsed: float = 0.0
func _ready() -> void:
_add_environment()
_add_light()
_add_ground()
for i in POINTERS:
var turn: float = TAU * i / POINTERS
pointers.append(_add_pointer(Vector3(cos(turn), 0, sin(turn)) * RING + Vector3(0, 1.1, 0), float(i) / POINTERS))
target = _add_target()
var camera: Camera3D = Camera3D.new()
camera.position = Vector3(0, 6.0, 11.5)
add_child(camera)
camera.look_at(Vector3(0, 2.0, 0), Vector3.UP)
camera.current = true
_aim()
print('every cone runs look_at on the yellow orb, so all eight track it at once')
func _process(delta: float) -> void:
elapsed += delta
# the orb stays inside the ring, so it never lines up with a cone and makes look_at singular
target.position = Vector3(
sin(elapsed * 0.8) * ROAM,
2.2 + sin(elapsed * 1.3) * 0.7,
cos(elapsed * 0.5) * ROAM
)
_aim()
func _aim() -> void:
for pointer in pointers:
pointer.look_at(target.position, Vector3.UP)
func _add_pointer(at: Vector3, hue: float) -> Node3D:
var cone: CylinderMesh = CylinderMesh.new()
cone.top_radius = 0.0
cone.bottom_radius = 0.5
cone.height = 1.8
cone.radial_segments = 12
var material: StandardMaterial3D = StandardMaterial3D.new()
material.albedo_color = Color.from_hsv(hue, 0.5, 0.95)
material.roughness = 0.45
# look_at aims the local -Z, and a cone from CylinderMesh grows along +Y
var visual: MeshInstance3D = MeshInstance3D.new()
visual.mesh = cone
visual.material_override = material
visual.rotation_degrees = Vector3(-90, 0, 0)
var base: CylinderMesh = CylinderMesh.new()
base.top_radius = 0.55
base.bottom_radius = 0.55
base.height = 0.25
var stand: MeshInstance3D = MeshInstance3D.new()
stand.mesh = base
stand.material_override = _make_material('#2a2f3d', 0.7)
var pointer: Node3D = Node3D.new()
pointer.position = at
pointer.add_child(visual)
add_child(pointer)
stand.position = Vector3(at.x, 0.12, at.z)
add_child(stand)
return pointer
func _add_target() -> Node3D:
var mesh: SphereMesh = SphereMesh.new()
mesh.radius = 0.75
mesh.height = 1.5
var material: StandardMaterial3D = StandardMaterial3D.new()
material.albedo_color = Color('#f3d48d')
material.emission_enabled = true
material.emission = Color('#f3d48d')
material.emission_energy_multiplier = 1.0
var orb: MeshInstance3D = MeshInstance3D.new()
orb.mesh = mesh
orb.material_override = material
orb.position = Vector3(0, 2.4, ROAM)
add_child(orb)
var glow: OmniLight3D = OmniLight3D.new()
glow.light_color = Color('#f3d48d')
glow.light_energy = 2.2
glow.omni_range = 14.0
orb.add_child(glow)
return orb
func _add_ground() -> void:
var mesh: PlaneMesh = PlaneMesh.new()
mesh.size = Vector2(300, 300)
var ground: MeshInstance3D = MeshInstance3D.new()
ground.mesh = mesh
ground.material_override = _make_material('#242938', 0.95)
add_child(ground)
func _make_material(hex: String, roughness: float) -> StandardMaterial3D:
var material: StandardMaterial3D = StandardMaterial3D.new()
material.albedo_color = Color(hex)
material.roughness = roughness
return material
func _add_environment() -> void:
var sky_material: ProceduralSkyMaterial = ProceduralSkyMaterial.new()
sky_material.sky_top_color = Color(0.07, 0.09, 0.18)
sky_material.sky_horizon_color = Color(0.26, 0.29, 0.4)
sky_material.ground_bottom_color = Color(0.05, 0.06, 0.09)
sky_material.ground_horizon_color = Color(0.18, 0.2, 0.28)
var sky: Sky = Sky.new()
sky.sky_material = sky_material
var env: Environment = Environment.new()
env.background_mode = Environment.BG_SKY
env.sky = sky
env.ambient_light_source = Environment.AMBIENT_SOURCE_SKY
env.ambient_light_energy = 0.75
var world: WorldEnvironment = WorldEnvironment.new()
world.environment = env
add_child(world)
func _add_light() -> void:
var light: DirectionalLight3D = DirectionalLight3D.new()
light.rotation_degrees = Vector3(-58, -35, 0)
light.light_energy = 1.1
add_child(light)