# Metview Macro

#  **************************** LICENSE START ***********************************
# 
#  Copyright 2018 ECMWF. This software is distributed under the terms
#  of the Apache License version 2.0. In applying this license, ECMWF does not
#  waive the privileges and immunities granted to it by virtue of its status as
#  an Intergovernmental Organization or submit itself to any jurisdiction.
# 
#  ***************************** LICENSE END ************************************

# ------------------------------------------------------------------
# Description: Demonstrates how to show a field using contour shading and
#              define a positional vertical legend.
# ------------------------------------------------------------------

# read the input grib file
my_data = read("t850.grb")

# set up the geographical view
my_view = geoview(map_area_definition : "CORNERS",
                  map_projection      : "CYLINDRICAL",
                  area                : [20.00,-20.00,70.00,50.00])

# set up the coastlines
my_coast = mcoast(map_coastline_thickness : 3,
                  map_grid_thickness      : 2,
                  map_grid_colour         : "GREY",
                  map_coastline_colour    : "RGB(0.4,0.4,0.4)",
                  map_grid                : "ON")

# set up the contour so that colour shading is used
my_contour = mcont(contour_level_selection_type   : "LEVEL_LIST",
                   contour_level_list             : [-20,-10,-5,-2.5,-1,-0.5,0,0.5,1,2.5,5,10,20,30],
                   contour_shade                  : "ON",
                   contour_shade_method           : "AREA_FILL",
                   contour_shade_colour_method    : "CALCULATE",
                   contour_shade_colour_direction : "CLOCKWISE",
                   contour_shade_max_level_colour : "RED",
                   contour_shade_min_level_colour : "BLUE",
                   contour_line_colour            : "GREY",
                   contour_line_thickness         : 2,
                   contour_highlight              : "OFF",
                   contour_label                  : "OFF",
                   legend                         : "ON")

# set up the position and properties of the legend
my_legend = mlegend(legend_title             : "ON",
                    legend_box_mode          : "POSITIONAL",
                    legend_box_x_position    : 26.00,
                    legend_box_x_length      : 2.00,
                    legend_box_y_position    : 2.00,
                    legend_box_y_length      : 10.00,
                    legend_display_type      : "CONTINUOUS",
                    legend_border            : "OFF",
                    legend_text_font_size    : 0.50,
                    legend_text_colour       : "NAVY",
                    legend_title_text        : "850hpa Temperature",
                    legend_title_orientation : "VERTICAL")

# set up the title
my_title = mtext(text_font_size     : 0.70,
                 text_lines         : ["Contour shading and positional legend.",
                                       "User-defined list of contour levels.",
                                       ""],
                 text_justification : "LEFT",
                 text_colour        : "CHARCOAL")


# define the output plot file
setoutput(pdf_output(output_name : 'contour5'))

# plot the data onto the map
plot(my_view,my_data,my_contour,my_legend,my_coast,my_title)