fix verlet integration, add wind

2 files changed, 34 insertions, 39 deletions

diff --git a/Scripts/cloth.js b/Scripts/cloth.js
index 038b235..266af16 100644
--- a/Scripts/cloth.js
+++ b/Scripts/cloth.js
@@ -373,7 +373,7 @@ getAcceleration(vertexIndex, dt) {
   // constant gravity

   let g = new THREE.Vector3(0, -9.8, 0);

   // stiffness

-  let k = 500;

+  let k = 1000;

 

   // Wind vector

   let fWind = new THREE.Vector3(

@@ -381,13 +381,12 @@ getAcceleration(vertexIndex, dt) {
     Math.cos(vertex.z * this.time),

     Math.sin(Math.cos(5 * vertex.x * vertex.y * vertex.z))

   );

-  fWind.set(0, 0, 0);

 

   /**

    * constant determined by the properties of the surrounding fluids (air)

    * achievement of cloth effects through try out

    * */

-  let a = 0.01;

+  let a = 0.1;

   

   let velocity = new THREE.Vector3(

     (this.previousPositions[vertexIndex].x - vertex.x) / dt,

@@ -490,13 +489,19 @@ verlet(currentPosition, previousPosition, acceleration, passedTime) {
   // next position = 2 * current Position - previous position + acceleration * (passed time)^2

   // acceleration (dv/dt) = F(net)

   // Dependency for one vertex: gravity, fluids/air, springs

-

+  const DRAG = 0.97;

   let nextPosition = new THREE.Vector3(

-    (2 * currentPosition.x) - previousPosition.x + acceleration.x * (passedTime * passedTime),

-    (2 * currentPosition.y) - previousPosition.y + acceleration.y * (passedTime * passedTime),

-    (2 * currentPosition.z) - previousPosition.z + acceleration.z * (passedTime * passedTime),

+    (currentPosition.x - previousPosition.x) * DRAG + currentPosition.x + acceleration.x * (passedTime * passedTime),

+    (currentPosition.y - previousPosition.y) * DRAG + currentPosition.y + acceleration.y * (passedTime * passedTime),

+    (currentPosition.z - previousPosition.z) * DRAG + currentPosition.z + acceleration.z * (passedTime * passedTime),

   );

 

+  // let nextPosition = new THREE.Vector3(

+  //   (2 * currentPosition.x) - previousPosition.x + acceleration.x * (passedTime * passedTime),

+  //   (2 * currentPosition.y) - previousPosition.y + acceleration.y * (passedTime * passedTime),

+  //   (2 * currentPosition.z) - previousPosition.z + acceleration.z * (passedTime * passedTime),

+  // );

+

   return nextPosition;

 }

 

@@ -510,5 +515,12 @@ euler(currentPosition, acceleration, passedTime) {
   return nextPosition;

 }

 

+wind(intersects) {

+  let intersect = intersects[0];

+  this.geometry.vertices[intersect.face.a].z -= 0.05;

+  this.geometry.vertices[intersect.face.b].z -= 0.05;

+  this.geometry.vertices[intersect.face.c].z -= 0.05;

+}

+

 }

 

diff --git a/Scripts/main.js b/Scripts/main.js
index 4e7c2ef..20a6e92 100644
--- a/Scripts/main.js
+++ b/Scripts/main.js
@@ -8,35 +8,6 @@ import { Face, Spring, Cloth } from './cloth.js';
  * evtl. an Stoff ziehen

  */

 

-

-class Point {

-  constructor(x, y) {

-    this.x = x;

-    this.y = y;

-  }

-

-  add(that) {

-    return new Point(

-      this.x + that.x,

-      this.y + that.y

-    );

-  }

-

-  sub(that) {

-    return new Point(

-      this.x - that.x,

-      this.y - that.y

-    );

-  }

-

-  dist(that) {

-    let a = this.x - that.x;

-    let b = this.y - that.y;

-    return Math.sqrt(a * a + b * b)

-  }

-}

-

-

 /**

  * setup THREE JS Scene, Camera and Renderer

  */

@@ -64,7 +35,7 @@ function setup_scene(canvasSpace) {
 document.body.onload = init;

 

 function init() {

-  let mousePos = new Point();

+  let mousePos = new THREE.Vector2();

   let previousClothSimulation;

   

   /**

@@ -99,6 +70,8 @@ function init() {
   const light = new THREE.DirectionalLight( 0xffffff, 0.5 );

   light.position.set( 0, 1, 0.5 );

   scene.add( light );

+  

+  let raycaster = new THREE.Raycaster();

 

   /**

    * function called every frame

@@ -107,17 +80,27 @@ function init() {
   function animate(dt) {

     cloth.simulate(dt/1000);

 

+    raycaster.setFromCamera( new THREE.Vector2((mousePos.x / w) * 2 - 1, ((h - mousePos.y) / h) * 2 - 1), camera );

+

+    const intersects = raycaster.intersectObject( mesh );

+

+    if ( intersects.length > 0 ) {

+      cloth.wind(intersects);

+    }

     setTimeout(() => {

       animate(frameTime);

     }, frameTime);

     renderer.render(scene, camera);

   }

 

+

   /** add callback for window resize */

   let canvas = document.getElementsByTagName("canvas")[0];

+  let w = window.innerWidth;

+  let h = window.innerHeight - canvasSpace;

   let resize = function () {

-    let w = window.innerWidth;

-    let h = window.innerHeight - 200;

+    w = window.innerWidth;

+    h = window.innerHeight - canvasSpace;

     canvas.width = w;

     canvas.height = h;

   }