/// \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));
}
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)) );
}