Using Arrows for Visualization

This is a demonstration of using several recently added graphics features in LAMMPS.

The simulation is a bulk water system that uses different ways to add arrows to the visualization:

• The endpoint coordinates of an arrow are computed using equal style variables from the output of compute dipole and then used in combination with fix graphics/objects to add a green arrow representing the total dipole moment vector in the center of the simulation box.
• Per molecule dipole vectors and their locations are computed with compute dipole/chunk and compute com/chunk and then visualized as yellow arrows using fix graphics/arrows.
• Per 3d-bin dipole vectors and their locations are computed with compute dipole/chunk and compute property/chunk and then visualized as pink arrows using fix graphics/arrows for a 2x2x2 set of 3d-bins.
• fix graphics/arrows is also used to visualize the atom velocity vectory (transparent blue).

For more information, see the LAMMPS Visualization Howto.