Exemple #1
0
/// \brief Keep the value of \p infinity as small as possible to improve precision in Winding_Clip.
void Winding_createInfinite(FixedWinding& winding, const Plane3& plane, double infinity)
{
  double max = -infinity;
  int x = -1;
  for (int i=0 ; i<3; i++)
  {
    double d = fabs(plane.normal()[i]);
    if (d > max)
    {
      x = i;
      max = d;
    }
  }
  if(x == -1)
  {
    globalErrorStream() << "invalid plane\n";
    return;
  }
    
  DoubleVector3 vup = g_vector3_identity;  
  switch (x)
  {
  case 0:
  case 1:
    vup[2] = 1;
    break;    
  case 2:
    vup[0] = 1;
    break;    
  }


  vector3_add(vup, vector3_scaled(plane.normal(), -vector3_dot(vup, plane.normal())));
  vector3_normalise(vup);
    
  DoubleVector3 org = vector3_scaled(plane.normal(), plane.dist());
  
  DoubleVector3 vright = vector3_cross(vup, plane.normal());
  
  vector3_scale(vup, infinity);
  vector3_scale(vright, infinity);

  // project a really big  axis aligned box onto the plane
  
  DoubleLine r1, r2, r3, r4;
  r1.origin = vector3_added(vector3_subtracted(org, vright), vup);
  r1.direction = vector3_normalised(vright);
  winding.push_back(FixedWindingVertex(r1.origin, r1, c_brush_maxFaces));
  r2.origin = vector3_added(vector3_added(org, vright), vup);
  r2.direction = vector3_normalised(vector3_negated(vup));
  winding.push_back(FixedWindingVertex(r2.origin, r2, c_brush_maxFaces));
  r3.origin = vector3_subtracted(vector3_added(org, vright), vup);
  r3.direction = vector3_normalised(vector3_negated(vright));
  winding.push_back(FixedWindingVertex(r3.origin, r3, c_brush_maxFaces));
  r4.origin = vector3_subtracted(vector3_subtracted(org, vright), vup);
  r4.direction = vector3_normalised(vup);
  winding.push_back(FixedWindingVertex(r4.origin, r4, c_brush_maxFaces));
}
Exemple #2
0
void vector3_test()
{
	vector3 zero = {0,0,0};
	vector3 one = {1,1,1};
	vector3 y = {0,1,0};
	vector3 half = {0.5,0.5,0.5};
	vector3 a;
	
	vector3_invert(&a, &one);
	vector3_subtract(&a, &one, &a);
	vector3_add(&a, &a, &one);
	vector3_print(&a);
	
	vector3_multiply(&a, &one, 0.5);
	vector3_divide(&a, &a, 2);
	vector3_print(&a);
	
	vector3_reflect(&a, &one, &y);
	vector3_print(&a);
	
	vector3_scalar_sub(&a, &zero, -0.5);
	vector3_scalar_add(&a, &a, 0.5);
	vector3_print(&a);
	
	vector3_cross(&a, &one, &y);
	vector3_print(&a);
	
	srand(3);
	vector3_random(&a);
	vector3_print(&a);
	
	printf("%.2f %.2f\n", 
		   vector3_dot(&half, &y), vector3_angle(&half, &y));
	
	printf("%.2f %.2f\n", 
		   vector3_distance(&one, &y), vector3_distancesq(&one, &y));
	
	vector3_copy(&a, &one);
	printf("%.2f %.2f\n", 
		   vector3_length(&one), vector3_length(vector3_normalize(&a)) );
}