`isocolors`

Computes the colors of isosurface vertices from a second volume of data.

Syntax

cdata = isocolors(X, Y, Z, C, verts)

Interpolates the volume C at the vertices verts.

cdata = isocolors(C, verts)

Uses the grid 1:n in each direction.

isocolors(___, p)

Sets the colors of the patch p directly.

Description

The shape of an isosurface comes from one variable, but you may want to color it by another, such as temperature over a pressure surface. isocolors samples that second volume at each vertex by interpolation. Assign the result to the FaceVertexCData property of the patch.

Input arguments

X, Y, Z: Coordinate arrays of the volume.
C: 3-D array of color values, or an m-by-n-by-p-by-3 array of RGB values.
verts: n-by-3 matrix of vertices, typically fv.vertices from isosurface.

Output arguments

cdata: One color value per vertex: a column vector for scalar data, or n-by-3 for RGB data.

Example

Color by a second field

[x, y, z] = meshgrid(-1:0.5:1);
v = x.^2 + y.^2 + z.^2;
fv = isosurface(x, y, z, v, 0.5);
c = isocolors(x, y, z, x, fv.vertices);
size(c)
min(c), max(c)

Output

ans = 1×2

    74     1
ans = -0.6667
ans = 0.6667

isocolors