Real
closestPtLineTriangle(Line3 const & line, Vector3 const & v0, Vector3 const & edge01, Vector3 const & edge02, Real & s,
Vector3 & c1, Vector3 & c2)
{
if (lineIntersectsTriangle(line, v0, edge01, edge02, &s))
{
c1 = c2 = line.getPoint() + s * line.getDirection();
return 0;
}
// Either (1) the line is not parallel to the triangle and the point of
// intersection of the line and the plane of the triangle is outside the
// triangle or (2) the line and triangle are parallel. Regardless, the
// closest point on the triangle is on an edge of the triangle. Compare
// the line to all three edges of the triangle.
Real min_sqdist = -1;
Vector3 v[3] = { v0, v0 + edge01, v0 + edge02 };
Vector3 tmp_c1, tmp_c2;
float tmp_s, t;
for (int i0 = 2, i1 = 0; i1 < 3; i0 = i1++)
{
Real sqdist = closestPtSegmentLine(v[i0], v[i1], line.getPoint(), line.getPoint() + line.getDirection(),
t, tmp_s, tmp_c2, tmp_c1);
if (min_sqdist < 0 || sqdist < min_sqdist)
{
min_sqdist = sqdist;
s = tmp_s;
c1 = tmp_c1;
c2 = tmp_c2;
}
}
return min_sqdist;
}
// clip this line segment against this triangle.
bool clip(const Vector3d &start,Vector3d &end) const
{
Vector3d sect;
bool hit = lineIntersectsTriangle(start.Ptr(), end.Ptr(), mP1.Ptr(), mP2.Ptr(), mP3.Ptr(), sect.Ptr() );
if ( hit )
{
end = sect;
}
return hit;
}
