Tutorial 3

This tutorial will cover representing a vector data field as a set of billboards overlaid with a arrow texture. This assumes you've done the other tutorials as well.

1. Star Eidolon and load a CHeart object with the files BORE_FE.X and BORE_FE.T from the tutorial/MeshData directory, with Tetrahedron as the geometry, 1 as the order, and Nodal Lagrange as the basis.

2. Load the field Vel-1.D with a dimension of 3, a topology file VBORE_FE.T which is Tetrahedron, order 2, Nodal Lagrange basis. It is important to note that this field uses its own topology distinct from the spatial topology, whereas in the previous tutorial the field implicitly used the spatial topology as its own.

3. Create a line representation with External Only checked so that lines are only made for the external faces.

4. Create a Glyphs representation with the following parameters:

• External Only unchecked
• Refinement set to 5
• Arrow selected from the Glyph drop-down box
• Dir Field and Scale Field set to Vel-1.D
• Choose Linear for Vector Func
• Choose AxisZ for Scale Func
• Input the values 0.0025, 0.0025, 0.01 for the Scale vector components

5. This will create a field of grey arrows pointing in various directions with various lengths. The zero-length arrows will look like disks because they've been squished entirely flat. Click on the new representation that comes up in the Objects box.

6. Select Rainbow as the material, Linear for the vector function, and Vel-1.D as the field, Magnitude for the value function, then click Apply. The results should look like this with Show Internal checked:

7. The script Tutorial3.py performs the equivalent of these steps.