bool Box3D::intersectsApprox(const Box3D& b) const
{
Box3D temp;
AABB3D aabb_temp, aabb_temp2;
//make temp localized
temp.dims = b.dims;
toLocal(b.origin, temp.origin);
toLocalReorient(b.xbasis, temp.xbasis);
toLocalReorient(b.ybasis, temp.ybasis);
toLocalReorient(b.zbasis, temp.zbasis);
temp.getAABB(aabb_temp);
aabb_temp2.bmin.setZero();
aabb_temp2.bmax = dims;
if(!aabb_temp2.intersects(aabb_temp))
return false;
temp.dims = dims;
b.toLocal(origin, temp.origin);
b.toLocalReorient(xbasis, temp.xbasis);
b.toLocalReorient(ybasis, temp.ybasis);
b.toLocalReorient(zbasis, temp.zbasis);
temp.getAABB(aabb_temp);
aabb_temp2.bmax = b.dims;
if(!aabb_temp2.intersects(aabb_temp))
return false;
return true;
}
bool ClipLine(const Vector3& x, const Vector3& v, const Box3D& b, Real& u1, Real& u2)
{
Vector3 x2, v2;
b.toLocal(x, x2);
//for each face, p is dot(v, normal), q is signed dist to plane (dot(v,normal)-offset)
//normal order: (-1,0,0), (1,0,0), (0,-1,0), (0,1,0), (0,0,-1), (0,0,1)
//offset order: 0, dims.x, 0, dims.y, 0, dims.z
v2.x=dot(v,b.xbasis);
if(ClipLine1D(-x2.x, -v2.x, u1,u2) && ClipLine1D(x2.x-b.dims.x, v2.x, u1,u2)) {
v2.y=dot(v,b.ybasis);
if(ClipLine1D(-x2.y, -v2.y, u1,u2) && ClipLine1D(x2.y-b.dims.y, v2.y, u1,u2)) {
v2.z=dot(v,b.zbasis);
if(ClipLine1D(-x2.z,-v2.z, u1,u2) && ClipLine1D(x2.z-b.dims.z, v2.z, u1,u2)) {
return true;
}
}
}
return false;
}