[Python] Creating evenly spaced non-solid lines with colormap

As an example I want to create a plot using z data as source for coloring using this code (modified from here:

import warnings

import matplotlib.pyplot as plt
import numpy as np

from matplotlib.collections import LineCollection


def colored_line(x, y, c, ax, **lc_kwargs):
if "array" in lc_kwargs:
warnings.warn('The provided "array" keyword argument will be overridden')

default_kwargs = {"capstyle": "butt"}
default_kwargs.update(lc_kwargs)

x = np.asarray(x)
y = np.asarray(y)
x_midpts = np.hstack((x[0], 0.5 * (x[1:] + x[:-1]), x[-1]))
y_midpts = np.hstack((y[0], 0.5 * (y[1:] + y[:-1]), y[-1]))

coord_start = np.column_stack((x_midpts[:-1], y_midpts[:-1]))[:, np.newaxis, :]
coord_mid = np.column_stack((x, y))[:, np.newaxis, :]
coord_end = np.column_stack((x_midpts[1:], y_midpts[1:]))[:, np.newaxis, :]
segments = np.concatenate((coord_start, coord_mid, coord_end), axis=1)

lc = LineCollection(segments, **default_kwargs)
lc.set_array(c) # set the colors of each segment

return ax.add_collection(lc)


# -------------- Create and show plot --------------
# Some arbitrary function that gives x, y, and color values
t = np.linspace(-7.4, -0.5, 200)
x = 0.9 * np.sin(t)
y = 0.9 * np.cos(1.6 * t)
color = np.linspace(0, 2, t.size)

# Create a figure and plot the line on it
fig1, ax1 = plt.subplots()
lines = colored_line(x, y, color, ax1, linewidth=1, cmap="plasma",linestyle="dashed")
fig1.colorbar(lines) # add a color

# Set the axis limits and tick positions
ax1.set_xlim(-1, 1)
ax1.set_ylim(-1, 1)
ax1.set_xticks((-1, 0, 1))
ax1.set_yticks((-1, 0, 1))
ax1.set_title("Color at each point")

plt.show()


# Create a figure and plot the line on it
fig1, ax1 = plt.subplots()
lines = colored_line(x, y, color, ax1, linewidth=1, cmap="plasma")
fig1.colorbar(lines) # add a color
ax1.plot(x,y, linestyle="dashed",color="white",linewidth=2,alpha=1)

# Set the axis limits and tick positions
ax1.set_xlim(-1, 1)
ax1.set_ylim(-1, 1)
ax1.set_xticks((-1, 0, 1))
ax1.set_yticks((-1, 0, 1))
ax1.set_title("Color at each point")

plt.show()


The first plot is the original approach adding the linestyle to the line collection leading to non-even spacing of the linestyle.

Denser spacing at curvature

The second is my simple approach of drawing the solid colored line and then drawing a white line on top of it creating even spacing. But this leads to problem in overlapping areas.

Even spacing

Is there a direct solution for my workaround that does not create funky new problems?

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