gistfile1.txt

THREE.Geometry.prototype.computeVertexNormalsWithCrease = function (maxSmoothAngle)
{
  var v, vl, f, fl, face,
    faceIndicesPerVertex = [];

  for (v = 0, vl = this.vertices.length; v < vl; v ++) {

    faceIndicesPerVertex.push([])

  }

  for (f = 0, fl = this.faces.length; f < fl; f ++) {

    face = this.faces[ f ];

    if ( face instanceof THREE.Face3 ) {

      faceIndicesPerVertex[face.a].push(f);
      faceIndicesPerVertex[face.b].push(f);
      faceIndicesPerVertex[face.c].push(f);

    } else if ( face instanceof THREE.Face4 ) {

      faceIndicesPerVertex[face.a].push(f);
      faceIndicesPerVertex[face.b].push(f);
      faceIndicesPerVertex[face.c].push(f);
      faceIndicesPerVertex[face.d].push(f);

    }

  }

  // for each face...

  for (f = 0, fl = this.faces.length; f < fl; f ++) {

    face = this.faces[ f ];

    var faceVertexCount;
    if ( face instanceof THREE.Face3 )
      faceVertexCount = 3;
    else if ( face instanceof THREE.Face4 )
      faceVertexCount = 4;
    else
      continue;

    // for each vertex of the face...

    for ( var fv = 0; fv < faceVertexCount; fv ++ ) {

      var vertexIndex = face[ 'abcd'.charAt( fv ) ];

      var vertexFaces = faceIndicesPerVertex[ vertexIndex ];

      var vertexNormal = face.normal.clone();

      // for each neighbouring face that shares this vertex...

      for ( var vf = 0; vf < vertexFaces.length; vf ++ ) {

        var neighbourFaceIndex = vertexFaces[vf];

        var neighbourFace = this.faces[neighbourFaceIndex];

        // disregard the face we're working with
        if (neighbourFace === face)
          continue;

        // given both normals are unit vectors, the angle is just acos(a.dot(b))
        var theta = Math.acos(face.normal.dot(neighbourFace.normal));

        if (theta <= maxSmoothAngle) {

          vertexNormal.add(neighbourFace.normal);

        }

      }

      vertexNormal.normalize();

      face.vertexNormals[ fv ] = vertexNormal;
    }

  }

}