#!/bin/bash
#========================================================================================
#          S V A L E X - 2 0 0 4  :  N a v d a t a   Q C   p l o t s 
#
# Using Gnuplot, generate png plots of shot point distances and DOL (Distance Off Line). 
#
# Dept. of Earth Science
# University of Bergen, Norway
#
# To create html page with thumbnail image gallery, install Igal and use this command:
#    igal -f -w 6 -y 120 -bigy 800
# Igal home page: http://www.stanford.edu/~epop/igal/
# 
# Rev.  Date            By         Description
# ------------------------------------------------------------------------
# 0.1   22. Nov. 2005   O. Meyer   Initial version. 
#========================================================================================

#--- Change these variables if needed

DIR="/home/olem/www/SVALEX-2004/Aleksandre/navdata"
GNUPLOT="/usr/bin/gnuplot"

for file in $(ls $DIR); do          # Loop over all files in target directory
   if [ ${file#*.} = txt ]; then    # Only process files with extension .txt. Use bash variable string operation to test filename extension.
      FILEPATH="$DIR/$file"
      echo -n "Plotting: $FILEPATH ... "
	
      #--- First calculate shot distance using Pythagoras.
      #--- Assuming we have shotpoint number in the first coloumn, and UTM coordinates in columns no. 3 and 4.
      #--- Value for the first shotpoint is meaningless, so use awk variable 'line' to get rid of this. 
      cat $FILEPATH | awk 'BEGIN {line=0} /^[0-9]/ {line+=1; if (line>1) print $1, sqrt(($3-x)**2+($4-y)**2); x = $3; y = $4}' > Shot_distance
      #--- Now get Shotpoint/DOL pairs and dump to file. Assuming DOL is in column no. 8
      cat $FILEPATH | awk '/^[0-9]/ {print $1,$8}' > DOL

      #--- Gnuplot section. Using the 'here document' method, script variables can be transfered to Gnuplot.
	
      $GNUPLOT << End_of_Gnuplot_section
         set terminal png color picsize 1100 800   # PNG terminal capabilities can vary ...
         set output "${file%.*}.png"               # Strip file extension, use 'png' instead. The variable 'file' is from 'for' loop above.
         set autoscale y2
         set grid
         set y2tics
         set ytics nomirror
         set y2tics nomirror
         #--- Now strip part of filename that starts with '_'. Assuming we have filename like 'Line10_LOG.txt'
         set title "SVALEX-2004: Plot of shot distance interval and DOL vs. shot number for ${file%_*}"
         set xlabel "Shot number"
         set ylabel "Shotpoint distance [m]"
         set y2label "DOL = Distance Off Line [m]"
         set key outside below box
         plot "Shot_distance" axis x1y1 with lines, "DOL" axis x1y2 with impulses
         #--- Final EOF must be positioned at left margin.
End_of_Gnuplot_section
      echo "done"
   fi
done

#--- Remove temp stuff

rm Shot_distance
rm DOL