Using the filter Sampling->Hausdorff Distance in MeshLab I computed the distance between a mesh and a target mesh.
How can I save the point to point distance and render it on a heat map or a plot it on a Histogram?
You can do it easy if you use the filter "Distance from reference mesh" instead of "Hausdorff Distance". That filter will leave the distance as a quality on each vertex of the Measured mesh.
After that, you can colorize the mesh using the filter "Colorize by vertex Quality" or save the mesh to plot the distances outside of meshlab. The recommended file format is Stanford Polygon File Format .ply, and ensure "Quality" checkbox is checked and "Binary encoding" is not checked. The output file has a 11 lines header and then a list with 4 numbers, XYZ and quality (which is the distance you are looking for your plot)
0 -2 0 1.902114
0 2 0 1.902113
1 -2 0 1.701302
0.9848077 -2 0.1736482 1.714225
0.9396926 -2 0.3420202 1.722303