Shapes on a polar plot -> is it posible?

📊 Plotly Python
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@openafox You cand define shapes in polar coordinates as filled closed curves. Below you find a function that defines the polar coordinates of the points on a circle of center (r0, theta0) and radius rho., as well as three shapes defined as go.Scatterpolar lines that define a filled close curve:

import plotly.graph_objects as go
import numpy as np
from numpy import pi, sin, cos, sqrt, arctan2

def circle(r0, theta0, rho, degrees = True):
    # compute the polar coordinates for 100 points on a circle of center (r0, theta0) and radius rho
    if degrees:
        theta0 = theta0 * pi / 180
    phi = np.linspace(0, 2*pi, 100)
    x = rho * cos(phi) + r0 * cos(theta0)
    y = rho * sin(phi) + r0 * sin(theta0)
    r = sqrt(x**2 + y**2)
    
    J = np.where(y<0)
    theta  = arctan2(y, x)
    theta[J]= theta[J] + 2*pi
    return (r, theta * 180 / pi) if degrees else (r, theta)
       

#define a general "shape"
fig = go.Figure(data = [go.Scatterpolar(
                        name = '',
                        r = [2, 3, 1, 4, 7, 5, 2, 2],
                        theta =  [57, 229, 114,  85, 85, 343, 286, 57],   
                        fill='toself',
                        mode='markers+lines',
                        marker_size=0.1)])


#define a curvilear rectangle
alpha = np.linspace(180,240, 60).tolist()
theta = alpha + alpha[::-1] + [alpha[0]]

fig.add_trace(go.Scatterpolar(r= [4]*60 + [6]*60+[4], 
                              theta =theta,
                              name='',
                              fill='toself'))
#define a filled circle
r, theta =  circle(4, 135, 1.5)    
fig.add_trace(go.Scatterpolar(r=r, theta=theta,
                              mode='lines', 
                              fill='toself', 
                              name=''));  
fig.update_layout(width=500, height=500, showlegend=False)

polar-shapes

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