Bug Report: hovertemplate in go.Surface doesn't work properly

[lhg1992]

The hovertemplate for go.Surface doesn't work properly, it can't display the user defined customdata nor 'text', it will only display the plain text as "cost: %{text}". Of course, I have also tried that it works well for go.Scatter and go. Scatter3d.

Check the following code, you can see the bug:

import plotly.graph_objects as go
import numpy as np

# Example data for the trajectory
x_traj = [0, 1, 2, 3, 4, 5]  # X-coordinates
y_traj = [0, 1, 4, 9, 16, 25]  # Y-coordinates
z_traj = [0, 1, 8, 27, 64, 125]  # Z-coordinates

# Example data for the contour
x = np.linspace(-10, 10, 100)
y = np.linspace(-10, 10, 100)
X, Y = np.meshgrid(x, y)
Z = np.sin(np.sqrt(X**2 + Y**2))  # Example Z values

# Create a 3D plot
fig = go.Figure()

# Add the 3D trajectory
fig.add_trace(go.Scatter3d(
    x=x_traj,
    y=y_traj,
    z=z_traj,
    text=[1,2,3,4,5,6],
    mode='lines+markers',  # Use 'lines' for trajectory and 'markers' for points
    line=dict(color='blue', width=2),  # Customize line color and width
    marker=dict(size=5, color='red'),  # Customize marker size and color
    hovertemplate="x: %{x:.2f}<br>y: %{y:.2f}<br>index: %{text}<br> <extra></extra>",
))

# Add the contour on Z=5 plane
fig.add_trace(go.Surface(
    x=x,
    y=y,
    z=np.full_like(Z, 5),  # Set Z=5 for the contour plane
    surfacecolor=Z,  # Use Z values for the contour colors
    text=Z,
    colorscale="Viridis",
    showscale=True,
    contours=dict(
        z=dict(
            show=True,
            start=-1,  # Minimum contour value
            end=1,     # Maximum contour value
            size=0.2,  # Step size between contours
            usecolormap=True,
            project_z=True  # Project contours onto the Z plane
        )
    ),
    opacity=0.7,  # Make the contour plane semi-transparent
    # hoverinfo="x+y+text", # works well
    hovertemplate="x: %{x:.2f}<br>y: %{y:.2f}<br>cost: %{text}<br> <extra></extra>", # doesn't work

))

# Update layout for better visualization
fig.update_layout(
    title="3D Trajectory with Contour on Z=5 Plane",
    scene=dict(
        xaxis_title="X Axis",
        yaxis_title="Y Axis",
        zaxis_title="Z Axis"
    ),
    width=800,
    height=600
)

# Show the plot
fig.show()

[jkoestner]

I've also had issues with go.Contour with hovertemplate. I switched to hoverinfo="text" and building out the text.

[lhg1992]

I've also had issues with go.Contour with hovertemplate. I switched to hoverinfo="text" and building out the text.

Yes, as shown in the code sample above, 'hoverinfo' works well. But the problem is that 'hoverinfo' can't control the display effect.