Cartopy: order of rendering layers with scatter data

Question

I am trying to plot position of several points (scatter plot) on a map using Cartopy (see code below). When I try to render the plot, data-points are rendered behind LAND-layer. But I want to plot my scatter-data over LAND-layer... What I am doing wrong?

Cartopy: ver. 0.12.x, Matplotlib: ver.1.4.2

import matplotlib.pyplot as plt
import cartopy.crs as ccrs
import cartopy.feature as cfeature 

ax = plt.axes(projection=ccrs.PlateCarree()) 
ax.set_extent([125, 150, 35, 63])         

ax.stock_img()

ax.add_feature(cfeature.LAND) #If I comment this => all ok, but I need 
ax.add_feature(cfeature.LAKES)
ax.add_feature(cfeature.RIVERS)
ax.coastlines()

ax.scatter(yc,xc,transform=ccrs.PlateCarree()) #yc, xc -- lists or numpy arrays

plt.show()

Points shown under the LAND layer

Plot without LAND-layer

try specifying a numerical `zorder`in your call to scatter. – Paul H Nov 14 '14 at 06:07 — Paul H, Nov 14 '14 at 06:07
Thanks! Setting up "zorder" solves the problem! – bubble Nov 14 '14 at 06:17 — bubble, Nov 14 '14 at 06:17
@PaulH - would you mind putting this as an answer? – pelson Nov 21 '14 at 17:54 — pelson, Nov 21 '14 at 17:54
@pelson answer has been posted. – Paul H Nov 21 '14 at 18:05 — Paul H, Nov 21 '14 at 18:05

score 14 · Accepted Answer · answered Nov 21 '14 at 18:04

14

Most, if not all, matplotlib plotting functions take a zorder parameter to specify the drawing order.

Lower zorders will be drawn first, and as such higher zorders will appear "on top".

So yeah, pass in zorder=xxx to arrange your layers.

answered Nov 21 '14 at 18:04

Paul H

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@pelson or @paul-h - I'm just curious, but why is this case? Sort of intuitively I would expect the scatter points to be 'on top' if the `plt.scatter` call is after the `ax.add_feature` calls. I had a similar problem to the OP and have to specify `zorder=2`. – decvalts Apr 23 '18 at 11:05
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@decvalts I couldn't tell you without inspecting the cartopy source code to check what the default zorders are. I don't have time for that, so I'll encourage you to do so. – Paul H Apr 23 '18 at 21:04

Cartopy: order of rendering layers with scatter data

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