Getting Plane Displayed from Cursors

Is it possible to get the plane which is currently displayed under a cursor.

i.e. A rcsr equivalent of pcsr and qcsr?
Nothing nice and conveniently built-in like that. But here's a function based on the WaveMetrics procedure file Graph Utility Procs that will get that information:
#include <Graph Utility Procs>

Function cursorLayer(graphname, csrname)
    String graphname, csrname
   
    if (strlen(graphname) == 0)
        graphname = winName(0,1)
    endif
   
    String info = CsrInfo($csrname, graphname)
    if (strlen(info) == 0)
        return NAN
    endif
    String tracename = StringByKey("TNAME", info)
    info = ImageInfo(graphname, tracename,0)
    if (strlen(info) == 0)
        return NAN
    endif
    String planestr = WMGetRECREATIONInfoByKey("plane", info)
    Variable value = strlen(planestr) == 0 ? NAN : str2num(planestr)
   
    return value
end

An example:
make/n=(10,10,10) junk=gnoise(1)
display;appendimage junk
ModifyImage junk plane= 4
ShowInfo

At this point, drag the A (round) cursor onto the image. Now:
print cursorlayer("", "a")
  4
print cursorlayer("", "b")
  NaN

John Weeks
WaveMetrics, Inc.
support@wavemetrics.com