1 files changed, 53 insertions, 24 deletions
diff --git a/Scripts/cloth.js b/Scripts/cloth.js
index 9389ef6..600ac8f 100644
--- a/Scripts/cloth.js
+++ b/Scripts/cloth.js
@@ -76,6 +76,11 @@ export class Spring {
 
     return direction;
   }
+
+  update(vertices) {
+    let length = vectorLength(vertices[this.index1], vertices[this.index2]);
+    this.currentLength = length;
+  }
 }
 
 /**
@@ -94,7 +99,7 @@ export class Cloth {
 
   vertexWeights = [];
 
-
+  vertexRigidness = [];
 
   /**
    * creates a rectangular piece of cloth
@@ -170,6 +175,12 @@ export class Cloth {
      * with generated vertices and faces
      */
     this.createExplicit(vertices, faces);
+
+    /**
+     * hand cloth from left and right upper corners
+     */
+    this.vertexRigidness[0] = true;
+    this.vertexRigidness[numPointsWidth-1] = true;
   }
 
   /**
@@ -189,6 +200,7 @@ export class Cloth {
       this.geometry.vertices.push(vertices[i]);
       this.previousPositions.push(vertices[i]);
       this.vertexWeights.push(0);
+      this.vertexRigidness.push(false);
     }
     /**
      * copy faces,
@@ -306,22 +318,30 @@ export class Cloth {
    * @param {number} dt 
    */
   simulate(dt) {
-
-
-
     for (let i in this.geometry.vertices) {
       let currentPosition;
       let acceleration = this.getAcceleration(i, dt);
+
+      // TODO: decide on clamping
+      acceleration.clampLength(0, 100);
  
-      currentPosition = this.verlet(this.geometry.vertices[i], this.previousPositions[i], acceleration, dt/2000);
+      currentPosition = this.verlet(this.geometry.vertices[i], this.previousPositions[i], acceleration, dt/500);
+      //currentPosition = this.euler(this.geometry.vertices[i], acceleration, dt/10);
      
       this.previousPositions[i] = currentPosition;
       this.geometry.vertices[i] = currentPosition;
-      
     }
-    console.log(this.geometry.vertices[0]);
+
+    //this.getAcceleration(1, dt, true);
+    
     this.time += dt;
 
+    for (let face of this.faces) {
+      for (let spring of face.springs) {
+        spring.update(this.geometry.vertices);
+      }
+    }
+
     /**
      * let THREE JS compute bounding sphere around generated mesh
      * needed for View Frustum Culling internally
@@ -341,22 +361,26 @@ export class Cloth {
  *  @param {number} dt The time passed since last frame
  */
 getAcceleration(vertexIndex, dt) {
+  if (this.vertexRigidness[vertexIndex])
+    return new THREE.Vector3(0, 0, 0);
 
   let vertex = this.geometry.vertices[vertexIndex];
 
   // Mass of vertex
   let M = this.vertexWeights[vertexIndex];
   // constant gravity
-  let g = new THREE.Vector3(0, -1.8, 0);
+  let g = new THREE.Vector3(0, -9.8, 0);
   // stiffness
-  let k = 5;
+  let k = 300;
 
   // Wind vector
+  // TODO: include wind vector
   let fWind = new THREE.Vector3(
     Math.sin(vertex.x * vertex.y * this.time),
     Math.cos(vertex.z* this.time),
     Math.sin(Math.cos(5 * vertex.x * vertex.y * vertex.z))
   );
+  fWind = new THREE.Vector3(0, 0, 0);
 
   /**
    * constant determined by the properties of the surrounding fluids (air)
@@ -365,17 +389,19 @@ getAcceleration(vertexIndex, dt) {
   let a = 1;
 
   let velocity = new THREE.Vector3(
-    (vertex.x - this.previousPositions[vertexIndex].x) / dt,
-    (vertex.y - this.previousPositions[vertexIndex].y) / dt,
-    (vertex.z - this.previousPositions[vertexIndex].z) / dt
+    (vertex.x - this.previousPositions[vertexIndex].x) * dt,
+    (vertex.y - this.previousPositions[vertexIndex].y) * dt,
+    (vertex.z - this.previousPositions[vertexIndex].z) * dt
   );
 
-
-  let fAirResistance = velocity.multiplyScalar(-a);
+  // TODO: include air resistance
+  let fAirResistance = velocity.multiply(velocity).multiplyScalar(-a);
+  fAirResistance = new THREE.Vector3(0, 0, 0);
 
   let springSum = new THREE.Vector3(0, 0, 0);
 
   // Get the bounding springs and add them to the needed springs
+  // TODO: optimize
   for (let i in this.faces) {
     if (this.faces[i].a == vertexIndex || this.faces[i].b == vertexIndex || this.faces[i].c == vertexIndex || this.faces[i].d == vertexIndex) {
       for (let j in this.faces[i].springs) {
@@ -385,26 +411,20 @@ getAcceleration(vertexIndex, dt) {
           let springDirection = spring.getDirection(this.geometry.vertices);
 
 
-          if (this.faces[i].springs[j].index1 == vertexIndex)
+          if (this.faces[i].springs[j].index2 == vertexIndex)
             springDirection.multiplyScalar(-1);
 
           springSum.add(springDirection.multiplyScalar(k * (spring.currentLength - spring.restLength)));
-
         }
       }
     }
   }
-
   
   let result = new THREE.Vector3(1, 1, 1);
 
-  
   result.multiplyScalar(M).multiply(g).add(fWind).add(fAirResistance).sub(springSum);
   
-
   return result;
-
-
 }
 
 /**
@@ -422,14 +442,23 @@ verlet(currentPosition, previousPosition, acceleration, passedTime) {
   // Dependency for one vertex: gravity, fluids/air, springs
 
   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),
+    (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;
 }
 
+euler(currentPosition, acceleration, passedTime) {
+  let nextPosition = new THREE.Vector3(
+    currentPosition.x + acceleration.x * passedTime,
+    currentPosition.y + acceleration.y * passedTime,
+    currentPosition.z + acceleration.z * passedTime,
+  );
+
+  return nextPosition;
+}
 
 }