How to ensure node points in gmsh? - numeric

Question

I am trying to build a quite simple mesh. I have a box:
box_size = 50;
lb = 10.;
Point(1) = {-box_size/2, -box_size/2, -box_size/2, lb};
Point(2) = {box_size/2, -box_size/2, -box_size/2, lb};
Point(3) = {box_size/2, box_size/2, -box_size/2, lb};
Point(4) = {-box_size/2, box_size/2, -box_size/2, lb};
Line(1) = {1, 2};
Line(2) = {2, 3};
Line(3) = {3, 4};
Line(4) = {4, 1};
Line Loop(5) = {1, 2, 3, 4};
Plane Surface(6) = {5};
Extrude {0, 0, box_size} {
Surface{6};
}
This works quite well and gmsh is happy to (3D) mesh it.
The problem is that I would to ensure that certain points inside the box are node points. So my question is, how do I ensure that points, like these
lc = 10;
Point(5) = {7.150548, 1.000000, -6.990684, lc};
Point(6) = {-4.438894, 1.000000, -8.960816, lc};
Point(7) = {-9.893936, 1.000000, 1.452595, lc};
Point(8) = {-1.675894, 1.000000, 9.858569, lc};
Point(9) = {8.858176, 1.000000, 4.640336, lc};
Point(10) = {1.675894, 4.750000, -9.858569, lc};
Point(11) = {-8.858176, 4.750000, -4.640336, lc};
Point(12) = {-7.150548, 4.750000, 6.990684, lc};
Point(13) = {4.438894, 4.750000, 8.960816, lc};
Point(14) = {9.893936, 4.750000, -1.452595, lc};
Point(15) = {7.150548, 8.500000, -6.990684, lc};
are part of the mesh?
The reason I need this is that I need to impose boundary conditions at these specific points.
If this is easier in another software, I am also happy to change. I hope someone can help.
Thank you in advance.

Answer 1

Quite a late answer but it might help anyway. If the index of the Point is p and the one of the volume or surface is q, then :
Point{p} In Volume {q};
Or if it is on a Surface :
Point{p} In Surface {q};

Answer 2

I believe the only option is to divide the structure such that they feature your points and mesh the structure after that. Now you can apply your loads and conditions on the Physical Points or Physical Lines.
Example: if you have a cube you want to mesh. And boundary condition is on the plane in the centre, then divide the cube at that plane. Make the plane a Physical entity, I.e., Physical Surface(14) = {midplane number}.mesh it all and you are good to go!