mapshow plot order

I am trying to plot a geotiff and a shapefile together in a map (not unlike the demo in help with the image and roads of Boston). However, when I use the commands, my shapefile ends up plotted behind the geotiff rather than above the image. My command looks like this (edited for simplicity):

mapshow(imagegrid, Rmapref) mapshow(shape)

the georeferencing in both Rmapref and shape is based in geographic (lat/long) coordinates rather than in x/y map coordinates, but memory issues were causing failure when plotting using geoshow. Any advice will help. Thanks.

[Neil Caithness]

I was about to post the same question but I'll add another example here.

[Z, R] = sdtsdemread('9129CATD.DDF');

mapshow(Z, R, 'DisplayType', 'surface')

x = [3.15 3.24]*10^5;

y = [4.91 4.91]*10^6;

hold on

plot(x,y,'*-k')

The points and line from the PLOT are obscured by the surface. How to bring these to the front? I think this is a general problem with surfaces and lines/points.

Answer 1

[Neil Caithness]

The solution I've found builds on the fact that even 2-d plotting is done in 3-d with an implied z=0. With MAPSHOW the surface is viewed from vertically above the X/Y plane, so any lines/points with a height of z=0 are obscured by map surface values >0.

One solution is to use PLOT3 with suitably large z values. Changing my example above:

[Z, R] = sdtsdemread('9129CATD.DDF'); 
mapshow(Z, R, 'DisplayType', 'surface') 
x = [3.15 3.24]*10^5; 
y = [4.91 4.91]*10^6; 
z = [1 1] + max(Z(:));
hold on 
plot3(x,y,z,'*-k')

Use the rotate button in the figure window to see what's going on.