View source for Linking surfaces into point models


Linking surfaces with point models is an useful way to get initial orientations of particles. The idea is to assign to each <tt>crop_point</tt> in the general model a <tt>crop_angle</tt> that is defined with reference to the support surface. Mathematically, ''Dynamo'' locates the closest triangle in the triangulation of the supporting surface, reads the normal, and formats it to provide the three euler angles needed to crop a particle.


== Command line==

Let's assume you have to models in your workspace: <tt>p</tt> is a general point model, and <tt>s</tt> is a surface model (for instance of class <tt>membraneByLevels</tt>)

Make certain that <tt>s</tt> contains already a depiction triangulation. This is created with the black triangle icon in the workflow for surfaces, or with the method <tt>createMesh</tt> from the command line.

Note that you can check visually the orientations of the particles in the model through the commands
 <tt>p.plotTableSketch([],'hold_limits',false);</tt>
which will show by default orientations pointing upward.

You can directly link the mesh inside surface  <tt>s</tt> into points <tt>p</tt> by:

 <tt>p.linkedSurface = s.mesh</tt>

After running this assignment the model <tt>p</tt> will be able to recompute its <tt>crop_angles</tt> with reference to its linked surface by:

 <tt>p.cropAnglesFromLinkedSurface();</tt>


=== Linking filaments ===
This technique can also be used to set orientations defined as normals from a filament. In this case, for a filament model <tt>f</tt>, the linkage is performed through:

 <tt>p.linkedBackbone = f.backbone</tt>