Order of traces affects visibility in Scatter3d

[ivirshup]

For 3d scatter plots with opacity < 1, the last trace to be added always shows up on top, regardless of camera position.

import numpy as np
from itertools import product

import plotly.graph_objs as go
import plotly.offline as py
py.init_notebook_mode(connected=True)

# Gen data
n = 10
r = np.arange(n)
a1 = np.zeros((n*n, 3))
a2 = np.zeros((n*n, 3))
for i, (x, y) in enumerate(product(r, r)):
    a1[i, :] = (x, y, -1)
    a2[i, :] = (x, y, 1)

# Gen traces
traces = list()
for i, a in enumerate((a1, a2)):
    trace = go.Scatter3d(
        x = a[:, 0],
        y = a[:, 1],
        z = a[:, 2],
        mode="markers",
        marker=dict(
            opacity=.99
        )
    )
    traces.append(trace)

# Plot
fig = go.Figure(data=traces)
py.iplot(fig)

When trace 1 should be on top:

When trace 0 should be on top:

[jonmmease]

Hi @ivirshup, thanks for the report.

I've opened a corresponding issue in the plotly.js project (plotly/plotly.js#2717), which is where the actual plot rendering logic lives. I'm going to close this issue, and we can continue the conversation with the plotly.js devs over there.

[jonmmease]

Updated issue: plotly/plotly.js#1267