rgb parameter for add_composite not working

[user27182]

Describe the bug, what's wrong, and what you expected.

If I plot a point cloud with the rgb option like this:

import pyvista as pv
import numpy as np

BLACK = [0.0, 0.0, 0.0]
WHITE = [1.0, 1.0, 1.0]
RED = [1.0, 0.0, 0.0]
GREEN = [0.0, 1.0, 0.0]
BLUE = [0.0, 0.0, 1.0]

rng = np.random.default_rng(seed=1)
points = rng.random((5, 3))

point_cloud = pv.PointSet(points)
point_cloud['colors'] = [WHITE, BLACK, RED, GREEN, BLUE]
point_cloud.plot(render_points_as_spheres = True, point_size = 100, rgb = True)

I get this result:

But if I try to plot each point as a multiblock like this:

white_point = pv.PointSet(points[0])
white_point['colors'] = [WHITE]
black_point = pv.PointSet(points[1])
black_point['colors'] = [BLACK]
red_point = pv.PointSet(points[2])
red_point['colors'] = [RED]
green_point = pv.PointSet(points[3])
green_point['colors'] = [GREEN]
blue_point = pv.PointSet(points[4])
blue_point['colors'] = [BLUE]

multiblock = pv.MultiBlock([white_point,black_point,red_point,green_point,blue_point])
multiblock.plot(render_points_as_spheres = True, point_size = 100, rgb = True)

I get this result:

I expected the second image to match the first. Not sure why they're colored red and blue.

The scalars in the multiblock seem to be ok

print(multiblock.combine()['colors'])

pyvista_ndarray([[0., 0., 0.],
                 [1., 1., 1.],
                 [1., 0., 0.],
                 [0., 1., 0.],
                 [0., 0., 1.]])

For reference, setting rgb=False with the multiblock produces this result:

Steps to reproduce the bug.

See above.

System Information

OS : Darwin
            CPU(s) : 8
           Machine : arm64
      Architecture : 64bit
               RAM : 16.0 GiB
       Environment : IPython
       File system : apfs
        GPU Vendor : Apple
      GPU Renderer : Apple M2
       GPU Version : 4.1 Metal - 88
  MathText Support : True
  Python 3.12.2 (v3.12.2:6abddd9f6a, Feb  6 2024, 17:02:06) [Clang 13.0.0
  (clang-1300.0.29.30)]
           pyvista : 0.44.dev0
               vtk : 9.3.0
             numpy : 1.26.4
        matplotlib : 3.8.2
            scooby : 0.9.2
             pooch : 1.8.0
            pillow : 10.2.0
           imageio : 2.34.0
           IPython : 8.21.0
          colorcet : 3.1.0
           cmocean : 3.1.3
        ipywidgets : 8.1.2
             scipy : 1.12.0
              tqdm : 4.66.2
            meshio : 5.3.5
        jupyterlab : 4.1.4
    pytest_pyvista : 0.1.8
             trame : 3.5.3
      trame_client : 2.16.1
      trame_server : 2.17.2
         trame_vtk : 2.8.5
     trame_vuetify : 2.4.3
      nest_asyncio : 1.6.0
--------------------------------------------------------------------------------

Screenshots

No response