NCL/ImageMagick example to tilt 3 contour plots into one new image#
Run the following KSH script:
ksh Tilting_3_Plots.ksh
Example KSH script Tilting_3_Plots.ksh:
#!/bin/ksh
#-----------------------------------------------------------------------------------
# DKRZ NCL example: Tilting_3_Plots.ksh
#
# Description: KSH-script to create 3 contour, 1 title and 1 labelbar plot
# generated by an NCL script, tilt the contour plots, and
# compose all with ImageMagick's 'convert' to one in portrait
# format.
#
# Graphic Software: NCL 6.3.0
# Image manipulation: ImageMagick 6.9.1-7
#
# 22.07.16 meier-fleischer(at)dkrz.de
#-----------------------------------------------------------------------------------
RUN_NCL=1 #-- run/skip NCL (1: do it; 0: skip)
RUN_COMPOSE=1 #-- run/skip ImageMagick distort/composite (1: do it; 0: skip)
NCL_SCRIPT="contour_plot.ncl" #-- name of the NCL script to be created (see below)
IFILE="rectilinear_grid_3D.nc" #-- data input file
#***********************************************
#-------------------------------
#-- write NCL script
#-------------------------------
cat << EOF > ${NCL_SCRIPT}
;---------------------------------------------------------------
; DKRZ NCL example: ${NCL_SCRIPT}
;
; Description: Create a contour plot in one frame,
; title and labelbar in another frame each.
;
; This script is part of the Pseudo_3D_plots
; examples to generate 3D looking images.
;
; NCL Version: 6.3.0
;
; 22.07.16 meier-fleischer(at)dkrz.de
;---------------------------------------------------------------
begin
title = "NCL contour plots tilted and composed by ImageMagick"
f = addfile("${IFILE}","r") ;-- open input file
var = f->t ;-- read variable
;-- lev = 100000, 92500, 85000, 77500, 70000, 60000, 50000, 40000, 30000, 25000,
;-- 20000, 15000, 10000, 7000, 5000, 3000, 1000 ;
slev = (/0,2,8/) ;-- choose levels for data to be plotted
;-- contour plot workstation
wks_type = "png"
wks_type@wkWidth = 2500
wks_type@wkHeight = 2500
wks_type@wkForegroundColor = "black"
wks_type@wkBackgroundOpacityF = 0.0
wks = gsn_open_wks(wks_type, "plot_contour")
;-- title plot workstation
wkst_type = "png"
wkst_type@wkWidth = 2500
wkst_type@wkHeight = 2500
wkst = gsn_open_wks(wkst_type, "plot_title")
;-- labelbar plot workstation
wksl_type = "png"
wksl_type@wkWidth = 2500
wksl_type@wkHeight = 2500
wksl = gsn_open_wks(wksl_type, "plot_labelbar")
;-- read color map and make the colors slightly transparent
cmap = read_colormap_file("BlueYellowRed") ;-- read RGBA colormap
cmap(:,3) = 0.8 ;-- 0: full transparent, 1: full opaque
;-------------------------------
;-- Contour plot:
;-------------------------------
res = True
res@gsnLeftString = "" ;-- no left string
res@gsnRightString = "" ;-- no right string
res@cnFillOn = True
res@cnFillPalette = cmap ;-- set color map
res@cnLinesOn = False ;-- turn off contour lines
res@cnLineLabelsOn = False ;-- turns off contour line labels
res@cnInfoLabelOn = False ;-- turns off contour info label
res@cnMissingValFillColor = "wheat4" ;-- missing value color
res@cnMissingValFillPattern = 0 ;-- 0: solid fill
res@cnLevelSelectionMode = "ManualLevels" ;-- use manual contour line levels
res@cnMinLevelValF = 230.0 ;-- contour min. value
res@cnMaxLevelValF = 320.0 ;-- contour max. value
res@cnLevelSpacingF = 5.0 ;-- contour interval
res@tmXTOn = True ;-- turn on tickmarks at top axis
res@tmXTLabelsOn = True ;-- draw tickmark labels
res@tmXTMajorLineColor = "black" ;-- choose top x-axis color
res@tmXTLabelFontColor = "black" ;-- choose top x-axis label color
res@tmXUseBottom = False ;-- do not use bottom x-axis
res@tmXBOn = False ;-- turn off tickmarks at bottom axis
res@tmYLOn = True ;-- turn on tickmarks at left axis
res@tmYLLabelsOn = True ;-- draw tickmark labels
res@tmYLMajorLineColor = "black" ;-- choose left y-axis color
res@tmYLLabelFontColor = "black" ;-- choose left y-axis label color
res@tmYUseLeft = True ;-- use left y-axis
res@mpGeophysicalLineThicknessF = 4.0 ;-- increase coastal outlines thicker
res@mpFillOn = False ;-- do not fill land areas
res@lbLabelBarOn = False ;-- don't draw labelbar
contour = gsn_csm_contour_map(wks,var(0,slev(2),:,:),res) ;-- create plot; advance contour frame
print(" - contour plot done: level = "+sprinti("%4i",toint(f->lev(slev(2))/100))+" hPa")
res@tmXTOn = False ;-- turn on tickmarks at top axis
res@tmYLOn = False ;-- turn on tickmarks at top axis
contour = gsn_csm_contour_map(wks,var(0,slev(1),:,:),res) ;-- create plot; advance contour frame
print(" - contour plot done: level = "+sprinti("%4i",toint(f->lev(slev(1))/100))+" hPa")
contour = gsn_csm_contour_map(wks,var(0,slev(0),:,:),res) ;-- create plot; advance contour frame
print(" - contour plot done: level = "+sprinti("%4i",toint(f->lev(slev(0))/100))+" hPa")
;-------------------------------
;-- Title plot:
;-------------------------------
tires = True
tires@txJust = "CenterCenter" ;-- text justification
tires@txFontHeightF = 0.017 ;-- text font size
tix = 0.5
tiy = 0.8
gsn_text_ndc(wkst,title,tix,tiy,tires) ;-- draw title
print(" - title plot done")
frame(wkst) ;-- advance title frame
;-------------------------------
;-- Labelbar plot:
;-------------------------------
;-- retrieve the contour resources for the labelbar
getvalues contour@contour
"cnLevels" : cnlevs ;-- contour levels
"cnFillColors" : cncols ;-- contour colors
"cnMonoFillPattern" : mpattern ;-- contour fill pattern
end getvalues
labels = ""+cnlevs ;-- labelbar labels
nboxes = dimsizes(cnlevs)+1 ;-- number of color boxes
lbx = 0.1 ;-- labelbar x-position
lby = 0.9 ;-- labelbar y-position
lbw = 0.8 ;-- labelbar width
lbh = 0.25 ;-- labelbar height
;-- labelbar resources
lbres = True
lbres@lbAutoManage = False ;-- we want to control the labelbar
lbres@lbOrientation = "horizontal" ;-- labelbar orientation
lbres@lbLabelFontHeightF = 0.024 ;-- increase label font size
lbres@lbLabelFontThicknessF = 4. ;-- increase label font thickness
lbres@lbLabelStride = 2 ;-- label every value
lbres@lbPerimOn = False ;-- no box around labelbar
lbres@lbLabelFontColor = "black" ;-- labe font color
lbres@lbLabelAlignment = "InteriorEdges" ;-- where to draw the labels
lbres@lbMonoFillPattern = mpattern ;-- use same fill pattern as contour plot
lbres@lbMonoFillColor = False ;-- use multiple colors
lbres@lbFillColors = cncols ;-- contour colors
lbres@lbLabelStrings = labels ;-- contour labels
lbres@lbBoxMinorExtentF = 0.15 ;-- change height of labelbar boxes
lbres@vpWidthF = lbw ;-- labelbar viewport width
lbres@vpHeightF = lbh ;-- labelbar viewport height
gsn_labelbar_ndc(wksl,nboxes,labels,lbx,lby,lbres) ;-- draw labelbar
;-- text resources labelbar annotations
txres = True
txres@txFontHeightF = 0.018 ;-- units text font size
gsn_text_ndc(wksl, "[C~S~o~N~]", 0.91, 0.75, txres) ;-- add units to labelbar
print(" - labelbar plot done")
frame(wksl) ;-- advance labelbar frame
print("")
end
EOF
#***********************************************
#-------------------------------------------------------------------
#-- run NCL scripts to generate the input images
#-------------------------------------------------------------------
if [[ $RUN_NCL == 1 ]] ; then
rm -rf plot_*.png #-- delete all old plots
echo "--------------------------------------------"
echo "** run NCL"
ncl -Q -n ${NCL_SCRIPT} #-- run NCL without standard output
fi
#-------------------------------------------------------------------
#-- do the tilting of the plot and create the composed plot
#-------------------------------------------------------------------
if [[ $RUN_COMPOSE == 1 ]] ; then
echo "--------------------------------------------"
echo "** run ImageMagick"
rm -rf compose.png #-- delete old composed file
#-- new width and height of sheared images 1685x2383
co1="plot_contour.000001.png"
co2="plot_contour.000002.png"
co3="plot_contour.000003.png"
co_width=2000 ; co_height=600
dxco1=25 ; dxco2=25 ; dxco3=1
dyco1=1370 ; dyco2=890 ; dyco3=400
angle=-40
#-- labelbar horizontal
lb="plot_labelbar.png"
lb_width=1335 ; lb_height=80
dxlb=225 ; dylb=2050
#-- title string
ti="plot_title.png"
ti_width=1500 ; ti_height=60
dxti=90 ; dyti=180
#-- cut off white space around te plot
alpha=on
bgc=white
convert -alpha $alpha -background $bgc -density 300 -trim $co1 tmp_c1.png
convert -alpha $alpha -background $bgc -density 300 -trim $co2 tmp_c2.png
convert -alpha $alpha -background $bgc -density 300 -trim $co3 tmp_c3.png
convert -alpha $alpha -background $bgc -density 300 -trim $ti tmp_t.png
convert -alpha $alpha -background $bgc -density 300 -trim $lb tmp_l.png
echo " - crop white space done"
#-- original and new coordinate positions of the edges for distortion
xul=0 ; dxul=400
yul=0 ; dyul=50
xur=2200 ; dxur=1500
yur=0 ; dyur=50
xlr=2200 ; dxlr=1900
ylr=1200 ; dylr=1200
xll=0 ; dxll=0
yll=1200 ; dyll=1200
#-- do the distortion and write the result to a temporary file
convert tmp_c1.png -alpha $alpha -virtual-pixel transparent \
-distort Perspective "$xul,$yul $dxul,$dyul \
$xur,$yur $dxur,$dyur \
$xlr,$ylr $dxlr,$dylr \
$xll,$yll $dxll,$dyll" tmp_contour_1.png
#-- do the distortion and write the result to a temporary file
convert tmp_c2.png -alpha $alpha -virtual-pixel transparent \
-distort Perspective "$xul,$yul $dxul,$dyul \
$xur,$yur $dxur,$dyur \
$xlr,$ylr $dxlr,$dylr \
$xll,$yll $dxll,$dyll" tmp_contour_2.png
#-- do the distortion and write the result to a temporary file
convert tmp_c3.png -alpha $alpha -virtual-pixel transparent \
-distort Perspective "$xul,$yul $dxul,$dyul \
$xur,$yur $dxur,$dyur \
$xlr,$ylr $dxlr,$dylr \
$xll,$yll $dxll,$dyll" tmp_contour_3.png
echo " - distortion done"
#-- compose all images a one new image of size (16:9 1688x3000)
font=Courier-Bold
convert -size 1685x2383 xc: \
\( tmp_contour_3.png -font $font -pointsize 42 -draw "text 10,500 '1000hPa'" -resize ${co_width}x${co_height}! \) \
-geometry +${dxco1}+${dyco1} -composite \
\( tmp_contour_2.png -font $font -pointsize 42 -draw "text 10,500 '850hPa'" -resize ${co_width}x${co_height}! \) \
-geometry +${dxco2}+${dyco2} -composite \
\( tmp_contour_1.png -font $font -pointsize 42 -draw "text 35,500 '300hPa'" -resize ${co_width}x${co_height}! \) \
-geometry +${dxco3}+${dyco3} -composite \
\( tmp_l.png -resize ${lb_width}x${lb_height}! \) -geometry +${dxlb}+${dylb} -composite \
\( tmp_t.png -resize ${ti_width}x${ti_height}! \) -geometry +${dxti}+${dyti} -composite \
tmp_compose.jpg
echo " - composition done"
#-- resize image to standard A3 842x1188(1920x1080) pixel size
convert -resize 842x1188 tmp_compose.jpg compose_3_tilted_plots.jpg
#-- clean up
rm -rf tmp_*.png tmp_*.jpg
fi
echo "--------------------------------------------"
#-------------------------------------------------------------------
exit
Result:
