plane_intersect.C

#include <string>
#include <iostream>
#include <iomanip>
#include <archon/math/geometry.H>
#include <archon/util/random.H>

using namespace std;
using namespace Archon::Math;
using namespace Archon::Utilities;

int main(int argc, const char *argv[]) throw()
{
  // The six planes of a box
  //   l - left
  //   r - right
  //   d - down
  //   u - up
  //   f - far
  //   n - near

  // Normals
  Vector3 n_l(-1,  0,  0);
  Vector3 n_r( 1,  0,  0);
  Vector3 n_d( 0, -1,  0);
  Vector3 n_u( 0,  1,  0);
  Vector3 n_f( 0,  0, -1);
  Vector3 n_n( 0,  0,  1);

  // Fixed points
  Vector3 p_l(-1,  0,  0);
  Vector3 p_r( 1,  0,  0);
  Vector3 p_d( 0, -1,  0);
  Vector3 p_u( 0,  1,  0);
  Vector3 p_f( 0,  0, -1);
  Vector3 p_n( 0,  0,  1);

  // Generate random but limited rotations
  Rotation3 r_l(drawUnitVector3(), M_PI/12);
  Rotation3 r_r(drawUnitVector3(), M_PI/12);
  Rotation3 r_d(drawUnitVector3(), M_PI/12);
  Rotation3 r_u(drawUnitVector3(), M_PI/12);
  Rotation3 r_f(drawUnitVector3(), M_PI/12);
  Rotation3 r_n(drawUnitVector3(), M_PI/12);

  // Distort normals
  Matrix3x3(r_l).map(n_l);
  Matrix3x3(r_r).map(n_r);
  //Matrix3x3(r_d).map(n_d);
  Matrix3x3(r_u).map(n_u);
  Matrix3x3(r_f).map(n_f);
  Matrix3x3(r_n).map(n_n);

  // Construct planes
  Plane3 pl_l(n_l, p_l);
  Plane3 pl_r(n_r, p_r);
  Plane3 pl_d(n_d, p_d);
  Plane3 pl_u(n_u, p_u);
  Plane3 pl_f(n_f, p_f);
  Plane3 pl_n(n_n, p_n);

  // Construct box corners as plane intersections
  Vector3 l_d_f = intersect(pl_l, pl_d, pl_f);
  Vector3 r_d_f = intersect(pl_r, pl_d, pl_f);
  Vector3 l_u_f = intersect(pl_l, pl_u, pl_f);
  Vector3 r_u_f = intersect(pl_r, pl_u, pl_f);
  Vector3 l_d_n = intersect(pl_l, pl_d, pl_n);
  Vector3 r_d_n = intersect(pl_r, pl_d, pl_n);
  Vector3 l_u_n = intersect(pl_l, pl_u, pl_n);
  Vector3 r_u_n = intersect(pl_r, pl_u, pl_n);

  // Print it
  cerr << setprecision(100)
       << l_d_f[0] << " " << l_d_f[1] << " " << l_d_f[2] << "\n"
       << r_d_f[0] << " " << r_d_f[1] << " " << r_d_f[2] << "\n"
       << l_u_f[0] << " " << l_u_f[1] << " " << l_u_f[2] << "\n"
       << r_u_f[0] << " " << r_u_f[1] << " " << r_u_f[2] << "\n"
       << "\n"
       << l_d_n[0] << " " << l_d_n[1] << " " << l_d_n[2] << "\n"
       << r_d_n[0] << " " << r_d_n[1] << " " << r_d_n[2] << "\n"
       << l_u_n[0] << " " << l_u_n[1] << " " << l_u_n[2] << "\n"
       << r_u_n[0] << " " << r_u_n[1] << " " << r_u_n[2] << "\n"
       << "\n";

  return 0;
}

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