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use rin::math::*;
use rin::graphics::{NodeRef, NodeMut};
use rin::events;
use rinecs::{Entities, Resources, Write, Read, ReadOption, Entity, CreationContext};
use crate::transformation::Transformation;
use crate::time::Clock;
use crate::Scene;
#[derive(Component, Clone, Debug, Serialize, Deserialize)]
pub struct Path(Polyline);
#[derive(Component, Clone, Debug, Serialize, Deserialize)]
pub struct Speed(f32);
impl Speed{
pub fn set(&mut self, d: f32){
self.0 = d
}
}
#[derive(Component, Clone, Debug, Serialize, Deserialize)]
pub struct Delta(f32);
impl Delta{
pub fn set(&mut self, d: f32){
self.0 = d
}
}
#[derive(Component, Clone, Debug, Serialize, Deserialize)]
pub struct CurrentPosition{
idx: usize,
pct: f64
}
impl CurrentPosition{
pub fn idx(&self) -> usize{
self.idx
}
pub fn fidx(&self) -> f64{
self.idx as f64 + self.pct
}
pub fn pct_current_segment(&self) -> f64{
self.pct
}
pub fn reset(&mut self){
self.idx = 0;
self.pct = 0.;
}
}
#[derive(Component, Debug, Serialize)]
pub struct Parameters{
pub doloop: events::Parameter<'static, bool>,
}
pub struct PathFollower;
impl crate::Bundle for PathFollower{
fn setup(self, world: &mut Scene){
world.add_system_with_name(path_follower, "path follower");
}
fn register(world: &mut Scene){
world.register_component::<Path>();
world.register_component::<Speed>();
world.register_component::<Delta>();
world.register_component::<CurrentPosition>();
}
}
#[derive(Filter)]
struct EntityWithPath<'a>{
transformation: Write<'a, Transformation>,
path: Read<'a, Path>,
speed: ReadOption<'a, Speed>,
delta: ReadOption<'a, Delta>,
current_position: Write<'a, CurrentPosition>,
}
impl<'a> EntityWithPath<'a>{
fn next_non_zero_segment(&mut self) -> Option<f32>{
self.path.next_non_zero_segment(self.current_position.idx)
.and_then(|idx| self.path.segment_length(idx))
}
fn arrived(&self) -> bool {
self.current_position.idx == self.path.len() - 1
}
}
fn path_follower(entities: Entities, resources: Resources){
let tdelta = resources.get::<Clock>()
.map(|clock| clock.last_frame_time()
.elapsed_game_time()
.as_seconds());
for mut entity in entities.iter_for::<EntityWithPath>(){
if !entity.path.is_empty() && (!entity.arrived() || entity.path.is_closed()){
let delta = if let Some(delta) = *entity.delta {
delta.0 as f64
}else{
tdelta.unwrap() * entity.speed.unwrap().0 as f64
};
if delta == 0. {
continue;
}
let segment_distance = entity.next_non_zero_segment();
if segment_distance.is_none() {
continue;
}
let segment_distance = segment_distance.unwrap();
let next_pct = entity.current_position.pct + delta / segment_distance as f64;
if next_pct > 1. {
entity.current_position.idx += 1;
if entity.path.is_closed() {
entity.current_position.idx = entity.path
.wrap_index(entity.current_position.idx as isize)
.unwrap();
}
if !entity.arrived() {
let rem = (1. - entity.current_position.pct) * segment_distance as f64;
if let Some(segment_distance) = entity.next_non_zero_segment(){
let rem_delta = delta - rem;
entity.current_position.pct = rem_delta / segment_distance as f64;
}else if !entity.path.is_closed() {
entity.current_position.idx = entity.path.len() - 1;
entity.current_position.pct = 0.;
}else{
continue;
}
}else{
entity.current_position.pct = 0.;
}
}else{
entity.current_position.pct = next_pct;
}
let fidx = entity.current_position.idx as f64 + entity.current_position.pct;
let next_position;
let next_direction;
if !entity.arrived() || entity.path.is_closed() {
next_position = entity.path.lerped_point_at(fidx as f32).unwrap();
next_direction = entity.path.lerped_tangent_at(fidx as f32);
}else{
next_position = *entity.path.last().unwrap();
next_direction = entity.path.tangent_at(entity.path.len() - 1);
}
entity.transformation.set_position(pnt3!(next_position, 0.));
if let Some(next_direction) = next_direction {
let curr_direction = -entity.transformation.y_axis().xy();
let delta_orientation = Rotation2::rotation_between(&curr_direction, &next_direction);
let delta_angle = Rad(delta_orientation.angle());
let delta_orientation = UnitQuat::from_axis_angle(&Vec3::z_axis(), delta_angle.value());
let dst_orientation = delta_orientation * entity.transformation.orientation();
entity.transformation.set_orientation(dst_orientation);
}
}
}
}
pub trait PathFollowerBuilder{
fn add_path_follower(&mut self, entity: &Entity, initial_speed: f32, path: Option<Polyline>);
fn add_path_follower_with_delta_provider(&mut self, entity: &Entity, path: Option<Polyline>);
}
impl<C: CreationContext> PathFollowerBuilder for C{
fn add_path_follower(&mut self, entity: &Entity, initial_speed: f32, path: Option<Polyline>){
let path = path.unwrap_or(Polyline::new());
self.add_component_to(entity, Path(path));
self.add_component_to(entity, Speed(initial_speed));
self.add_component_to(entity, CurrentPosition{idx: 0, pct: 0.});
}
fn add_path_follower_with_delta_provider(&mut self, entity: &Entity, path: Option<Polyline>){
let path = path.unwrap_or(Polyline::new());
self.add_component_to(entity, Path(path));
self.add_component_to(entity, Delta(0.));
self.add_component_to(entity, CurrentPosition{idx: 0, pct: 0.});
}
}