#!/bin/bash # # Developed by Fred Weinhaus 5/30/2008 .......... revised 11/5/2014 # # ------------------------------------------------------------------------------ # # Licensing: # # Copyright © Fred Weinhaus # # My scripts are available free of charge for non-commercial use, ONLY. # # For use of my scripts in commercial (for-profit) environments or # non-free applications, please contact me (Fred Weinhaus) for # licensing arrangements. My email address is fmw at alink dot net. # # If you: 1) redistribute, 2) incorporate any of these scripts into other # free applications or 3) reprogram them in another scripting language, # then you must contact me for permission, especially if the result might # be used in a commercial or for-profit environment. # # My scripts are also subject, in a subordinate manner, to the ImageMagick # license, which can be found at: http://www.imagemagick.org/script/license.php # # ------------------------------------------------------------------------------ # #### # # USAGE: anglegradient widthxheight [-a angle] [-c color ] outfile # USAGE: anglegradient [-h or -help] # # OPTIONS: # # widthxheight widthxheight of gradient image # -a angle orientational angle for gradient; # degrees rotation from a vertical in # clockwise direction; default=0; # or nw,ne,se,sw for diagonal # -c colors gradient coloration; any valid # hyphenated color pair involving # opaque colors or "none" # ### # # NAME: ANGLEGRADIENT # # PURPOSE: To create a gradient effect at a specific orientation angle. # # DESCRIPTION: ANGLEGRADIENT creates a gradient effect at a specific # orientation angle. # # OPTIONS: # # widthxheight ... WIDTHxHEIGHT are the dimensions of the gradient image. # # -a angle ... ANGLE is the angle for the gradient coloration in degrees. # Values must be greater than or equal to 0 and less than or equal to 360. # Alternately, values of nw, ne, se, or sw may be specified to have the # diagonal angle automatically, computed. For angle=0, the gradient will # have the first color at the top and the second color at the bottom. As # the gradient-angle is increased, the gradient rotates clockwise. The # default=0. # # -c colors ... COLORS is any valid hyphenated IM color pair including # opaquecolor-opaquecolor, opaquecolor-none or none-opaquecolor for a # transition from one opaque color to another or to transparency. If no # color pair is specified, then the normal grayscale gradient will be # generated. For angle=0, the first color will be at the top and the # second color at the bottom of the gradient image. # # NOTE: This script requires IM 6.4.2-6 or higher due to the use of # -distort SRT. # # CAVEAT: No guarantee that this script will work on all platforms, # nor that trapping of inconsistent parameters is complete and # foolproof. Use At Your Own Risk. # ###### # # set default values angle=0 colors="white-black" size="" # set directory for temporary files dir="." # suggestions are dir="." or dir="/tmp" # set up functions to report Usage and Usage with Description PROGNAME=`type $0 | awk '{print $3}'` # search for executable on path PROGDIR=`dirname $PROGNAME` # extract directory of program PROGNAME=`basename $PROGNAME` # base name of program usage1() { echo >&2 "" echo >&2 "$PROGNAME:" "$@" sed >&2 -e '1,/^####/d; /^###/g; /^#/!q; s/^#//; s/^ //; 4,$p' "$PROGDIR/$PROGNAME" } usage2() { echo >&2 "" echo >&2 "$PROGNAME:" "$@" sed >&2 -e '1,/^####/d; /^######/g; /^#/!q; s/^#*//; s/^ //; 4,$p' "$PROGDIR/$PROGNAME" } # function to report error messages errMsg() { echo "" echo $1 echo "" usage1 exit 1 } # function to test for minus at start of value of second part of option 1 or 2 checkMinus() { test=`echo "$1" | grep -c '^-.*$'` # returns 1 if match; 0 otherwise [ $test -eq 1 ] && errMsg "$errorMsg" } # test for correct number of arguments and get values if [ $# -eq 0 ] then # help information echo "" usage2 exit 0 elif [ $# -gt 6 ] then errMsg "--- TOO MANY ARGUMENTS WERE PROVIDED ---" else while [ $# -gt 0 ] do # get parameter values case "$1" in -h|-help) # help information echo "" usage2 exit 0 ;; -a) # get angle shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID ANGLE SPECIFICATION ---" checkMinus "$1" angle=`echo "$1" | tr "[:upper:]" "[:lower:]"` if [ "$angle" != "ne" -a "$angle" != "se" -a "$angle" != "sw" -a "$angle" != "nw" ]; then angle=`expr "$1" : '\([.0-9]*\)'` [ "$angle" = "" ] && errMsg "--- ANGLE=$angle MUST BE A NON-NEGATIVE FLOAT ---" angletestA=`echo "$angle < 0" | bc` angletestB=`echo "$angle > 360" | bc` [ $angletestA -eq 1 -o $angletestB -eq 1 ] && errMsg "--- ANGLE=$angle MUST BE A FLOAT BETWEEN 0 AND 360 ---" fi ;; -c) # get colors shift # to get the next parameter # test if parameter starts with minus sign errorMsg="--- INVALID COLORS SPECIFICATION ---" checkMinus "$1" colors="$1" ;; [0-9]*x[0-9]*) # get size size="$1" numdim=`echo "$size" | tr "x" " " | wc -w` [ $numdim -ne 2 ] && errMsg "--- TWO DIMENSIONS MUST BE PROVIDED ---" ww=`echo "$size" | cut -dx -f1` hh=`echo "$size" | cut -dx -f2` ;; -) # STDIN and end of arguments break ;; -*) # any other - argument errMsg "--- UNKNOWN OPTION ---" ;; *) # end of arguments break ;; esac shift # next option done # # get infile and outfile outfile="$1" fi # test that outfile provided [ "$outfile" = "" ] && errMsg "--- NO OUTPUT FILE SPECIFIED ---" # test if size specified [ "$size" = "" ] && errMsg "--- GRADIENT SIZE HAS NOT BEEN SPECIFIED ---" # get IM version im_version=`convert -list configure | \ sed '/^LIB_VERSION_NUMBER */!d; s//,/; s/,/,0/g; s/,0*\([0-9][0-9]\)/\1/g' | head -n 1` # test if IM version compatible with -distort SRT # (earliest is IM 6.3.5-1 but possibly not stable until IM v6.4.2-6) [ "$im_version" -lt "06040206" ] && errMsg "--- IM VERSION IS NOT COMPATIBLE WITH -DISTORT SRT ---" # get max dimension maxdim=`convert xc: -format "%[fx:max($ww,$hh)]" info:` # test if square testsq=`convert xc: -format "%[fx:($ww==$hh)?1:0]" info:` if [ $testsq -eq 1 ]; then operation1="" else operation1="-gravity center -crop ${ww}x${hh}+0+0 +repage" fi # separate colors numcolors=`echo "$colors" | tr "-" " " | wc -w` [ $numcolors -ne 2 ] && errMsg "--- TWO COLORS MUST BE PROVIDED ---" color1=`echo "$colors" | cut -d- -f1` color2=`echo "$colors" | cut -d- -f2` # set up colorpair and operations if [ "$color1" != "none" -a "$color2" != "none" ]; then colorpair="gray(255)-gray(0)" operation2="+level-colors ${color2},${color1}" operation3="-delete 0" elif [ "$color1" != "none" -a "$color2" = "none" ]; then colorpair="gray(255)-gray(0)" operation2="-fill $color1 -colorize 100%" operation3="+swap -alpha off -compose copy_opacity -composite" elif [ "$color1" = "none" -a "$color2" != "none" ]; then colorpair="gray(0)-gray(255)" operation2="-fill $color2 -colorize 100%" operation3="+swap -alpha off -compose copy_opacity -composite" fi # setup diagonal directions if needed if [ "$angle" = "ne" ]; then angle=`convert xc: -format "%[fx:(180/pi)*atan2($hh,$ww)]" info:` elif [ "$angle" = "nw" ]; then angle=`convert xc: -format "%[fx:360+(180/pi)*atan2(-$hh,$ww)]" info:` elif [ "$angle" = "sw" ]; then angle=`convert xc: -format "%[fx:360+(180/pi)*atan2(-$hh,-$ww)]" info:` elif [ "$gradangle" = "se" ]; then angle=`convert xc: -format "%[fx:(180/pi)*atan2($hh,-$ww)]" info:` fi #echo "colors=$colors; colorpair=$colorpair; op1=$operation1; op2=$operation2; angle=$angle" # process gradient if [ "$angle" = "0" ]; then convert -size $size gradient:"$colors" "$outfile" elif [ "$color1" != "none" -a "$color2" != "none" ]; then convert \( -size ${maxdim}x${maxdim} gradient:"$colorpair" \ -distort SRT "$angle" $operation1 -contrast-stretch 0 \) \ \( -clone 0 $operation2 \) \ $operation3 \ "$outfile" else convert \( -size ${maxdim}x${maxdim} gradient:"$colorpair" \ -distort SRT "$angle" $operation1 -contrast-stretch 0 \) \ \( -clone 0 $operation2 \) \ $operation3 \ "$outfile" fi exit 0