[Python] Make 3D stack of multiple 2D images with color gradient

I have a set of 10 2D images that I want to stack to make a 3D image. These images are generated using matplotlib so they can be either .png or .tif. In the sample code below, I have a function plot_data() that uses gen_random_data() to get a line and plot a set of 10 2D images where the gradient color is based on the viridis() cmap. I have used meshlib.mrmeshpy to stack these images to get the 3D plot but this 3D image is not color graded. Can someone please help me implement the color I have as well? If there is another package apart from meshlib.mrmeshpy that can do this, please let me know.

This is the code I have:

import cv2
import meshlib.mrmeshpy as mr
import vtk
import matplotlib.pyplot as plt
import numpy as np
import os

def gen_random_data():
# Generate random data
np.random.seed(42)
x = np.random.rand(100, 100)
y = 2 * x + 5
# z = np.random.rand(100, 100)
return x, y


def plot_data(n=10):
for i in range(n):
# Generate random data
x, y = gen_random_data()
# Plot the data
plt.scatter(x, y, c=y)
plt.viridis()
plt.savefig('scatter_plots/scatter_plot_{}.tif'.format(i))
plt.show()


def make_stack(tif_path):

settings = mr.LoadingTiffSettings()

# load images from specified directory
settings.dir = tif_path

# specifiy size of 3D image element
settings.voxelSize = mr.Vector3f(1, 1, 5)

#create voxel object from the series of images
volume = mr.loadTiffDir(settings)

#define ISO value to build surface
iso = 100.0 #127.0

#convert voxel object to mesh
mesh = mr.gridToMesh(volume, iso)

#save mesh to .stl file
mr.saveMesh(mesh, mr.Path(tif_path + '/' + '3d_image_stack.stl'))


def view_stack(tif_path):
# visualize the file:
reader = vtk.vtkSTLReader()
reader.SetFileName(tif_path + '/' + '3d_image_stack.stl')

mapper = vtk.vtkPolyDataMapper()
mapper.SetInputConnection(reader.GetOutputPort())

actor = vtk.vtkActor()
actor.SetMapper(mapper)

renderer = vtk.vtkRenderer()
renderer.AddActor(actor)
renderer.SetBackground(1, 1, 1)

render_window = vtk.vtkRenderWindow()
render_window.AddRenderer(renderer)
render_window.SetSize(800, 800)

interactor = vtk.vtkRenderWindowInteractor()
interactor.SetRenderWindow(render_window)

interactor.Initialize()
interactor.Start()


def main():
# Plot and provide path to TIF images
plot_data(10)
TIF_PATH = r'scatter_plots'

make_stack(TIF_PATH)
view_stack(TIF_PATH)


if __name__ == '__main__':
main()


This code will generate the images and make a 3D plot. I have tried playing with the iso value but it does not affect the color.

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