trainsim/main.ts

import { lerp } from "./math/lerp.ts";
import { ComplexPath, PathSegment } from "./math/path.ts";
import { Mover } from "./physics/mover.ts";
import { Train, TrainCar } from "./train.ts";
import { fillCircle, drawCircle } from 'drawing';
import { generateSquareTrack, IControlNode, loadFromJson } from "./track.ts";
import { drawLine } from "./drawing/line.ts";
import { initializeDoodler, Vector } from 'doodler';



const engineSprites = document.createElement('img');
engineSprites.src = './sprites/EngineSprites.png';
engineSprites.style.display = 'none';
engineSprites.id = 'engine-sprites';
document.body.append(engineSprites);

initializeDoodler({
  width: 400,
  height: 400,
  bg: '#333'
});

const path = loadFromJson();

const controls = {
  ArrowUp: false,
  ArrowRight: false,
  ArrowDown: false,
  ArrowLeft: false,
}

let t = 0;
let currentSeg = 0;
let speed = 1;

// const trainCount = 1;
// const trains = Array(trainCount).fill(null).map((_, i) => new Train(path.segments[i % path.segments.length], 5));
const car = new TrainCar(55, engineSprites, 80, 20, {at: new Vector(0, 80), height: 20, width: 80})
const train = new Train(path, [car]);

let dragEndCounter = 0
let selectedNode: IControlNode | undefined;

doodler.createLayer(() => {
  for (let i = 0; i < path.evenPoints.length; i+=10) {
    const p = path.evenPoints[i];
    const next = path.evenPoints[(i + 1)%path.evenPoints.length];
    const last = path.evenPoints.at(i - 1);
    if (!last) break;
    const tan = Vector.sub(last, next);

    doodler.drawRotated(p, tan.heading(), () => {
      doodler.line(p, p.copy().add(0,10), {color: '#291b17', weight: 4})
      doodler.line(p, p.copy().add(0,-10), {color: '#291b17', weight: 4})
      doodler.line(p.copy().add(-6,5), p.copy().add(6,5), {color: 'grey', weight: 2})
      doodler.line(p.copy().add(-6,-5), p.copy().add(6,-5), {color: 'grey', weight: 2})
    })
  }
  path.draw();
  train.move();

  selectedNode?.anchor.drawDot();
  selectedNode?.controls.forEach(e => e.drawDot());
})

let editable = false;

const clickables = new Map()

let selectedPoint: Vector;

document.addEventListener('keyup', e => {
  if (e.key === 'd') {
    // console.log(trains)
    // console.log(path.segments.reduce((a,b) => a + b.calculateApproxLength(1000), 0))
    // console.log(path.evenPoints);
  }

  if (e.key === 'ArrowUp') {
    // for (const train of trains) {
    //   train.speed += .1;
    // }
    speed += .1
  }
  if (e.key === 'ArrowDown') {
    // for (const train of trains) {
    //   train.speed -= .1;
    // }
    speed -= .1
  }

  if (e.key === 'm' && selectedPoint) {
    const points = path.points;
    const index = points.findIndex(p => p === selectedPoint);
    if (index > -1) {
      const prev = points.at(index - 1)!;
      const next = points[(index + 1) % points.length];

      const toPrev = Vector.sub(prev, selectedPoint);
      toPrev.setMag(next.dist(selectedPoint));
      toPrev.rotate(Math.PI)
      const toNext = Vector.add(toPrev, selectedPoint);
      next.set(toNext);

      path.calculateApproxLength();
      path.calculateEvenlySpacedPoints(1);
    }
  }

  if (e.key === 'e') {
    editable = !editable;
    for (const t of path.segments) {
      t.editable = !t.editable;
      for (const p of t.points) {
        if (t.editable) {
          doodler.registerDraggable(p, 10)
          doodler.addDragEvents({
            point: p,
            onDragEnd: () => {
              dragEndCounter++
              t.length = t.calculateApproxLength(100)
              path.evenPoints = path.calculateEvenlySpacedPoints(1)
            },
            onDrag: (movement) => {
              // todo - remove ! after updating doodler
              path.handleNodeEdit(p, movement!)
            }
          })
        }
        else {
          doodler.unregisterDraggable(p)
        }
      }
    }
    for (const p of path.points) {
      if (editable) {
        const onClick = () => {
          selectedPoint = p;
          selectedNode = path.nodes.find(e => e.anchor === p || e.controls.includes(p));
        }

        clickables.set(p, onClick);
        doodler.registerClickable(p.copy().sub(10, 10), p.copy().add(10, 10), onClick);
      }
      else {
        const the = clickables.get(p);
        doodler.unregisterClickable(the);
      }
    }
  }
})

// document.addEventListener('keydown', e => {
//   const valid = ["ArrowUp",
//     "ArrowRight",
//     "ArrowDown",
//     "ArrowLeft",]
//   if (valid.includes(e.key))
//     controls[e.key as keyof typeof controls] = true;
// })
// document.addEventListener('keyup', e => {
//   const valid = ["ArrowUp",
//     "ArrowRight",
//     "ArrowDown",
//     "ArrowLeft",]
//   if (valid.includes(e.key))
//     controls[e.key as keyof typeof controls] = false;
// })

// function getSteeringForce(mover: Mover, dir: string) {
//   const dirs = {
//     ArrowUp: 0,
//     ArrowRight: .1 * Math.PI,
//     ArrowDown: Math.PI,
//     ArrowLeft: -.1 * Math.PI,
//   }

//   const target = mover.velocity.copy();
//   target.normalize();
//   target.mult(10);
//   target.rotate(dirs[dir as keyof typeof dirs]);
//   const force = Vector.sub(target, mover.velocity);
//   force.limit(.1)
//   return force;
// }

document.addEventListener('keydown', e => {
  if (e.ctrlKey && e.key === 's') {
    e.preventDefault();
    path.segments.forEach((s: any) => {
      s.next = s.next.id
      s.prev = s.prev.id
      delete s.ctx
    })
    delete path.ctx;
    const json = JSON.stringify(path);
    localStorage.setItem('railPath', json);
  }
})