trunk/src/wall.cc

   1 // Voro++, a 3D cell-based Voronoi library
   2 //
   3 // Author   : Chris H. Rycroft (LBL / UC Berkeley)
   4 // Email    : chr@alum.mit.edu
   5 // Date     : August 30th 2011
   6
   7 /** \file wall.cc
   8  * \brief Function implementations for the derived wall classes. */
   9
  10 #include "wall.hh"
  11
  12 namespace voro {
  13
  14 /** Tests to see whether a point is inside the sphere wall object.
  15  * \param[in,out] (x,y,z) the vector to test.
  16  * \return True if the point is inside, false if the point is outside. */
  17 bool wall_sphere::point_inside(double x,double y,double z) {
  18         return (x-xc)*(x-xc)+(y-yc)*(y-yc)+(z-zc)*(z-zc)<rc*rc;
  19 }
  20
  21 /** Cuts a cell by the sphere wall object. The spherical wall is approximated by
  22  * a single plane applied at the point on the sphere which is closest to the center
  23  * of the cell. This works well for particle arrangements that are packed against
  24  * the wall, but loses accuracy for sparse particle distributions.
  25  * \param[in,out] c the Voronoi cell to be cut.
  26  * \param[in] (x,y,z) the location of the Voronoi cell.
  27  * \return True if the cell still exists, false if the cell is deleted. */
  28 template<class v_cell>
  29 bool wall_sphere::cut_cell_base(v_cell &c,double x,double y,double z) {
  30         double xd=x-xc,yd=y-yc,zd=z-zc,dq=xd*xd+yd*yd+zd*zd;
  31         if (dq>1e-5) {
  32                 dq=2*(sqrt(dq)*rc-dq);
  33                 return c.nplane(xd,yd,zd,dq,w_id);
  34         }
  35         return true;
  36 }
  37
  38 /** Tests to see whether a point is inside the plane wall object.
  39  * \param[in] (x,y,z) the vector to test.
  40  * \return True if the point is inside, false if the point is outside. */
  41 bool wall_plane::point_inside(double x,double y,double z) {
  42         return x*xc+y*yc+z*zc<ac;
  43 }
  44
  45 /** Cuts a cell by the plane wall object.
  46  * \param[in,out] c the Voronoi cell to be cut.
  47  * \param[in] (x,y,z) the location of the Voronoi cell.
  48  * \return True if the cell still exists, false if the cell is deleted. */
  49 template<class v_cell>
  50 bool wall_plane::cut_cell_base(v_cell &c,double x,double y,double z) {
  51         double dq=2*(ac-x*xc-y*yc-z*zc);
  52         return c.nplane(xc,yc,zc,dq,w_id);
  53 }
  54
  55 /** Tests to see whether a point is inside the cylindrical wall object.
  56  * \param[in] (x,y,z) the vector to test.
  57  * \return True if the point is inside, false if the point is outside. */
  58 bool wall_cylinder::point_inside(double x,double y,double z) {
  59         double xd=x-xc,yd=y-yc,zd=z-zc;
  60         double pa=(xd*xa+yd*ya+zd*za)*asi;
  61         xd-=xa*pa;yd-=ya*pa;zd-=za*pa;
  62         return xd*xd+yd*yd+zd*zd<rc*rc;
  63 }
  64
  65 /** Cuts a cell by the cylindrical wall object. The cylindrical wall is
  66  * approximated by a single plane applied at the point on the cylinder which is
  67  * closest to the center of the cell. This works well for particle arrangements
  68  * that are packed against the wall, but loses accuracy for sparse particle
  69  * distributions.
  70  * \param[in,out] c the Voronoi cell to be cut.
  71  * \param[in] (x,y,z) the location of the Voronoi cell.
  72  * \return True if the cell still exists, false if the cell is deleted. */
  73 template<class v_cell>
  74 bool wall_cylinder::cut_cell_base(v_cell &c,double x,double y,double z) {
  75         double xd=x-xc,yd=y-yc,zd=z-zc,pa=(xd*xa+yd*ya+zd*za)*asi;
  76         xd-=xa*pa;yd-=ya*pa;zd-=za*pa;
  77         pa=xd*xd+yd*yd+zd*zd;
  78         if(pa>1e-5) {
  79                 pa=2*(sqrt(pa)*rc-pa);
  80                 return c.nplane(xd,yd,zd,pa,w_id);
  81         }
  82         return true;
  83 }
  84
  85 /** Tests to see whether a point is inside the cone wall object.
  86  * \param[in] (x,y,z) the vector to test.
  87  * \return True if the point is inside, false if the point is outside. */
  88 bool wall_cone::point_inside(double x,double y,double z) {
  89         double xd=x-xc,yd=y-yc,zd=z-zc,pa=(xd*xa+yd*ya+zd*za)*asi;
  90         xd-=xa*pa;yd-=ya*pa;zd-=za*pa;
  91         pa*=gra;
  92         if (pa<0) return false;
  93         pa*=pa;
  94         return xd*xd+yd*yd+zd*zd<pa;
  95 }
  96
  97 /** Cuts a cell by the cone wall object. The conical wall is
  98  * approximated by a single plane applied at the point on the cone which is
  99  * closest to the center of the cell. This works well for particle arrangements
 100  * that are packed against the wall, but loses accuracy for sparse particle
 101  * distributions.
 102  * \param[in,out] c the Voronoi cell to be cut.
 103  * \param[in] (x,y,z) the location of the Voronoi cell.
 104  * \return True if the cell still exists, false if the cell is deleted. */
 105 template<class v_cell>
 106 bool wall_cone::cut_cell_base(v_cell &c,double x,double y,double z) {
 107         double xd=x-xc,yd=y-yc,zd=z-zc,xf,yf,zf,q,pa=(xd*xa+yd*ya+zd*za)*asi;
 108         xd-=xa*pa;yd-=ya*pa;zd-=za*pa;
 109         pa=xd*xd+yd*yd+zd*zd;
 110         if(pa>1e-5) {
 111                 pa=1/sqrt(pa);
 112                 q=sqrt(asi);
 113                 xf=-sang*q*xa+cang*pa*xd;
 114                 yf=-sang*q*ya+cang*pa*yd;
 115                 zf=-sang*q*za+cang*pa*zd;
 116                 pa=2*(xf*(xc-x)+yf*(yc-y)+zf*(zc-z));
 117                 return c.nplane(xf,yf,zf,pa,w_id);
 118         }
 119         return true;
 120 }
 121
 122 // Explicit instantiation
 123 template bool wall_sphere::cut_cell_base(voronoicell&,double,double,double);
 124 template bool wall_sphere::cut_cell_base(voronoicell_neighbor&,double,double,double);
 125 template bool wall_plane::cut_cell_base(voronoicell&,double,double,double);
 126 template bool wall_plane::cut_cell_base(voronoicell_neighbor&,double,double,double);
 127 template bool wall_cylinder::cut_cell_base(voronoicell&,double,double,double);
 128 template bool wall_cylinder::cut_cell_base(voronoicell_neighbor&,double,double,double);
 129 template bool wall_cone::cut_cell_base(voronoicell&,double,double,double);
 130 template bool wall_cone::cut_cell_base(voronoicell_neighbor&,double,double,double);
 131
 132 }