Recursive Subdivision

​

​

class Face {

​

​

  Vec3D a;

  Vec3D b;

  Vec3D c;

​

  Face(Vec3D _a,Vec3D _b,Vec3D _c) {

    a = _a;

    b = _b;

    c = _c;

  }

​

​

  void run() {

​

    float period = 1000;

    float amplitude = 4;

    int ite = int(amplitude * cos(TWO_PI * frameCount / period))+4;

​

​

    iterate(a,b,c, ite);

  }

​

​

  void iterate(Vec3D v1, Vec3D v2,Vec3D v3,int gens) {

​

​

​

    //Vec3D cen = calcCentroid(v1,v2,v3);

​

    Vec3D cen = calcCentroid2(v1,v2,v3);

​

​

    Vec3D nor = calcNormal(v1,v2,v3);

​

    float len = calcLen(v1,v2,v3);

​

    Vec3D dispPt = drawVector(cen, nor, len/30);

​

​

    if( gens == 0) {

      display(v1, v2, v3);

    }

​

    if( gens > 0) {

​

      iterate(v1, v2, dispPt, gens-1); 

      iterate(v2, v3, dispPt, gens-1); 

      iterate(v3, v1, dispPt, gens-1);

    }

  }

​

​

​

  float calcLen(Vec3D v1, Vec3D v2, Vec3D v3) {

​

    float len = 0;

​

    Vec3D dif1 = v1.sub(v2);

    Vec3D dif2 = v2.sub(v3);

    Vec3D dif3 = v3.sub(v1);

​

    float m1 = dif1.magnitude();

    float m2 = dif2.magnitude();

    float m3 = dif3.magnitude();

​

    len = m1 + m2 + m3;

​

​

    return len;

  }

​

​

​

​

  Vec3D drawVector (Vec3D p, Vec3D v, float sca) {

​

    Vec3D vec = v.copy();

    vec.normalize();

    vec.scaleSelf(sca);

​

    vec.addSelf(p);

​

    stroke(255,0,0);

    //vLine(p,vec);

​

    return vec;

  }

​

  void vLine(Vec3D v1, Vec3D v2) {

    line(v1.x,v1.y, v1.z,v2.x,v2.y,v2.z );

  }

​

​

  Vec3D calcCentroid2(Vec3D v1, Vec3D v2, Vec3D v3) {

​

    Vec3D md1 = mdPt(v1,v2);

    Vec3D md2 = mdPt(v2,v3);

    Vec3D md3 = mdPt(v3,v1);

​

    //vLine(v1, md2);

​

    Vec3D sub1 = md1.sub(v3);

    //float m1 = sub1.magnitude();

    //sub1.normalize();

    sub1.scaleSelf(1);

    sub1.addSelf(md1);

​

    Vec3D sub2 = md2.sub(v1);

    sub2.scaleSelf(1);

    sub2.addSelf(md2);

​

    Vec3D sub3 = md3.sub(v2);

    sub3.scaleSelf(1);

    sub3.addSelf(md3);

​

​

    Vec3D sum  = new Vec3D();

    sum.addSelf(sub1);

    sum.addSelf(sub2);

    sum.addSelf(sub3);

​

    sum.scaleSelf(1.0/3.0);

​

    //vPt(sum);

​

    return sum;

  }

​

  Vec3D mdPt(Vec3D v1, Vec3D v2) {

​

    Vec3D md1 = v2.sub(v1);

    md1.scaleSelf(1.0/2);

    md1.addSelf(v1);

​

    //stroke(0,0,255);

    //strokeWeight(5);

    //vPt(md1);

​

    return md1;

  }

​

  Vec3D calcNormal(Vec3D v1, Vec3D v2, Vec3D v3) {

​

    Vec3D dif1 = v1.sub(v2);

    dif1.normalize();

    Vec3D dif2 = v1.sub(v3);

    dif2.normalize();

​

    Vec3D cros = dif1.cross(dif2);

    cros.normalize();

​

    return cros;

  }

​

​

​

  Vec3D calcCentroid(Vec3D v1, Vec3D v2, Vec3D v3) {

    Vec3D sum = v1.add(v2);

    sum.addSelf(v3);

​

    sum.scaleSelf(1.0/3.0);

​

    stroke(255,0,0);

    // strokeWeight(5);

    //vPt(sum);

​

    return sum;

  }

​

​

  void display(Vec3D v1, Vec3D v2, Vec3D v3) {

​

    stroke(255,90);

    fill(0,255,170,80);

    beginShape();

    vex(v1);

    vex(v2);

    vex(v3);

    vex(v1);

    endShape();

  }

​

  void vPt(Vec3D v) {

    point(v.x,v.y,v.z);

  }

​

  void vex(Vec3D v) {

    vertex(v.x,v.y,v.z);

  }

}

​

​