Mayavi: interpolate face colors in triangular_mesh

Question

I have pieced together the following code to plot a triangular mesh with the colors specified by an additional scalar function: ``` #! /usr/bin/env python import numpy as np from mayavi import mlab # Create cone n = 8 t = np.linspace(-np.pi, np.pi, n) z = np.exp(1j*t) x = z.real.copy() y = z.imag.copy() z = np.zeros_like(x) triangles = [(0, i, i+1) for i in range(n)] x = np.r_[0, x] y = np.r_[0, y] z = np.r_[1, z] t = np.r_[0, t] # These are the scalar values for each triangle f = np.mean(t[np.array(triangles)], axis=1) # Plot it mesh = mlab.triangular_mesh(x, y, z, triangles, representation='wireframe', opacity=0) cell_data = mesh.mlab_source.dataset.cell_data cell_data.scalars = f cell_data.scalars.name = 'Cell data' cell_data.update() mesh2 = mlab.pipeline.set_active_attribute(mesh, cell_scalars='Cell data') mlab.pipeline.surface(mesh2) mlab.show() ``` This works reasonably well. However, instead of having every triangle with a uniform color and sharp transitions between the triang…

Accepted Answer

I think you want to use point data instead of cell data. With cell data, a single scalar value is not localized to any point. It is assigned to the entire face. It looks like you just want to assign the `t` data to the vertices instead. The default rendering of point scalars will smoothly interpolate across each face.

```
point_data = mesh.mlab_source.dataset.point_data
point_data.scalars = t
point_data.scalars.name = 'Point data'
point_data.update()

mesh2 = mlab.pipeline.set_active_attribute(mesh,
        point_scalars='Point data')
```

Mayavi: interpolate face colors in triangular_mesh

Solution

Problem