X-Git-Url: https://gitweb.ps.run/cloth_sim/blobdiff_plain/999a549825d3de0b53e2922462ed1e120e176ec2..8199b09231f15b0f84480656a0e92827d795fcdc:/Scripts/cloth.js

diff --git a/Scripts/cloth.js b/Scripts/cloth.js
index 0c4f02c..ff55549 100644
--- a/Scripts/cloth.js
+++ b/Scripts/cloth.js
@@ -4,7 +4,9 @@ const MASS = 0.1;
 const GRAVITY = new THREE.Vector3(0, -9.81 * MASS, 0);
 const K = 1;
 
-let tmpCorrection;
+const options = {
+  wind: true,
+};
 
 class Constraint {
   constructor(p1, p2, restDist) {
@@ -18,16 +20,28 @@ class Constraint {
     const currentDist = diff.length();
     if (currentDist == 0) return;
     if (currentDist <= this.restDist) return;
-    const correction = diff.multiplyScalar(1 - (this.restDist / currentDist));
+    //const correction = diff.multiplyScalar(1 - (this.restDist / currentDist));
+    const correction = diff.multiplyScalar((currentDist - this.restDist) / currentDist);
     correction.multiplyScalar(K);
-    tmpCorrection = correction;
+    correction.clampLength(0, 1);
     const correctionHalf = correction.multiplyScalar(0.5);
-    this.p1.position.add(correctionHalf);
-    this.p2.position.sub(correctionHalf);
+
+    let p1movable = this.p1.movable && this.p1.movableTmp;
+    let p2movable = this.p2.movable && this.p2.movableTmp;
+
+    if (p1movable && p2movable) {
+      this.p1.position.add(correctionHalf);
+      this.p2.position.sub(correctionHalf);
+    } else if (! p1movable && p2movable) {
+      this.p2.position.sub(correction);
+    } else if (p1movable && ! p2movable) {
+      this.p1.position.add(correction);
+    }
   }
 }
 
 class Particle {
+  movableTmp = true;
   movable = true;
 
   constructor(x, y, z, mass) {
@@ -50,8 +64,10 @@ class Particle {
     nextPosition.add(this.position);
     nextPosition.add(this.acceleration.multiplyScalar(dt*dt));
 
-    this.previous = this.position;
-    this.position = nextPosition;
+    if (this.movable && this.movableTmp) {
+      this.previous = this.position;
+      this.position = nextPosition;
+    }
 
     this.acceleration.set(0, 0, 0);
   }
@@ -63,7 +79,7 @@ class Cloth {
     this.height = height;
     this.numPointsWidth = numPointsWidth;
     this.numPointsHeight = numPointsHeight;
-    this.windFactor = new THREE.Vector3(0.5, 0.2, 0.2);
+    this.windFactor = new THREE.Vector3(3, 2, 2);
 
     /**
      * distance between two vertices horizontally/vertically
@@ -90,9 +106,12 @@ class Cloth {
       }
     }
 
-    this.particles[this.getVertexIndex(0, 0)].movable = false;
-    this.particles[this.getVertexIndex(0, numPointsHeight-1)].movable = false;
-    this.particles[this.getVertexIndex(numPointsWidth-1, 0)].movable = false;
+    //this.particles[this.getVertexIndex(0, 0)].movable = false;
+    const n = 3;
+    for (let i = 0; i < numPointsHeight; i++)
+      this.particles[this.getVertexIndex(0, i)].movable = false;
+    //this.particles[this.getVertexIndex(0, numPointsHeight-1)].movable = false;
+    //this.particles[this.getVertexIndex(numPointsWidth-1, 0)].movable = false;
 
     const REST_DIST_X = width / (numPointsWidth-1);
     const REST_DIST_Y = height / (numPointsHeight-1);
@@ -168,13 +187,9 @@ class Cloth {
     const positions = geometry.attributes.position.array;
     for (let i in this.particles) {
       let p = this.particles[i];
-      if (p.movable) {
-        positions[i*3+0] = p.position.x;
-        positions[i*3+1] = p.position.y;
-        positions[i*3+2] = p.position.z;
-      } else {
-        p.position = p.previous;
-      }
+      positions[i*3+0] = p.position.x;
+      positions[i*3+1] = p.position.y;
+      positions[i*3+2] = p.position.z;
     }
     geometry.attributes.position.needsUpdate = true;
     geometry.computeBoundingSphere();
@@ -190,7 +205,8 @@ class Cloth {
         this.windFactor.z * Math.sin(Math.cos(5 * vertex.x * vertex.y * vertex.z))
       );
       // normalize then multiply?
-      particle.addForce(fWind);
+      if (options.wind)
+        particle.addForce(fWind);
       // calculate wind with normal?
 
       particle.addForce(GRAVITY);
@@ -202,8 +218,42 @@ class Cloth {
     for (let constraint of this.constraints) {
       constraint.satisfy();
     }
-    //console.log(tmpCorrection);
+
+    this.intersect();
   }
+
+  intersect() {
+    let npw = this.numPointsWidth;
+    function getX(i) { return i % npw; }
+    function getY(i) { return Math.floor(i / npw); }
+
+    for (let i in this.particles) {
+      for (let j in this.particles) {  
+        let p1 = this.particles[i];
+        let p2 = this.particles[j];
+
+        p1.movableTmp = true;
+        p2.movableTmp = true;
+
+        if (i == j || (Math.abs(getX(i) - getX(j)) == 1 && Math.abs(getY(i) - getY(j)) == 1))
+          continue;
+
+        let dist = p1.position.distanceTo(p2.position);
+        const collisionDistance = Math.min(this.width / this.numPointsWidth, this.height / this.numPointsHeight);
+        if (dist < collisionDistance) {
+          p1.movableTmp = false;
+          p2.movableTmp = false;
+          let diff = p1.position.clone().sub(p2.position).normalize();
+          diff.multiplyScalar((collisionDistance - dist) * 1.001 / 2);
+          if (p1.movable)
+            p1.position.add(diff);
+          if (p2.movable)
+            p2.position.sub(diff);
+        }
+      }
+    }
+  }
+
   /**
    * helper function to calculate index of vertex
    * in "vertices" array based on its x and y positions