Import HGT Python SOP.

gistfile1.py

from struct import unpack, calcsize

def loadHGT( filename, row, row_length ):
    data = []
    try:
        f = open( filename, 'rb' )
        format = '!H'
        f.seek( row * row_length * calcsize(format) )
        for i in xrange(row_length):
            data.append( unpack(format, f.read(calcsize(format)))[0] )
        
        f.close()
    except:
        pass

    return data

filename   = hou.pwd().parm("filename").evalAsString()
w          = hou.pwd().parm("width").evalAsFloat()
# Row Length probably 1201 or 3601
row_length = hou.pwd().parm("row_length").evalAsInt()
hs         = hou.pwd().parm("height_scale").evalAsFloat()
skip       = hou.pwd().parm("skip").evalAsInt()

if (w*row_length*skip) != 0:

    geo = hou.pwd().geometry()

    ofs = w / row_length
    z = -w / 2.0
    for row in xrange(0, row_length, skip):
        # Can't wait cooking? then press ESC:
        if hou.updateProgressAndCheckForInterrupt():
            break
        rdata = loadHGT( filename, row, row_length )
        x = -w / 2.0
        for i in xrange(0, len(rdata)-1, skip):
            p = geo.createPoint()
            p.setPosition( (x + ofs * i, float(rdata[i]) * hs, z + ofs * row) )