Fix a longstanding issue with subplots containing colorbars. (#1906)

The solution is a workaround because true cause lies in an inaccessible part of the C library.

Author: joa-quim

src/segy/segy.jl

@@ -3,7 +3,7 @@
 
 Plot a SEGY file as a seismic data image.
 """
-segy!(cmd0::String; kwargs...) = segy_helper(cmd0; first=false, kwargs...)
+segy!(cmd0::String; kwargs...) = segy(cmd0; first=false, kwargs...)
 function segy(cmd0::String; first=true, kw...)
 	#(cmd0 === "") && error("Missing input segY file name to run this module.")
 	d, K, O = init_module(first==1, kw...)		# Also checks if the user wants ONLY the HELP mode
@@ -49,7 +49,7 @@ end
 
 Plot a SEGY file in 3-D as a seismic data image.
 """
-segyz!(cmd0::String; kwargs...) = segyz_helper(cmd0; first=false, kwargs...)
+segyz!(cmd0::String; kwargs...) = segyz(cmd0; first=false, kwargs...)
 function segyz(cmd0::String; first=true, kw...)
 	d, K, O = init_module(first==1, kw...)		# Also checks if the user wants ONLY the HELP mode
 	segyz_helper(cmd0, O, K, d)

src/subplot.jl

@@ -113,6 +113,7 @@ function subplot(fim::String, stop::Bool, d::Dict{Symbol, Any})
 			gmt("gmtset  MAP_FRAME_TYPE fancy")
 		catch; resetGMT()
 		end
+		remove_map_origin()		# Remove MAP_ORIGIN_X and MAP_ORIGIN_Y from the gmt.conf.0.subplot file (see comments in function)
 		IamSubplot[], IamModern[] = true, true
 	elseif (do_set)
 		(!IamSubplot[]) && error("Cannot call subplot(set, ...) before setting dimensions")
@@ -216,4 +217,31 @@ function mura_arg(arg)::Dict
 	else                                d = (isa(arg, NamedTuple)) ? nt2dict(arg) : arg
 	end
 	d
+end
+
+# --------------------------------------------------------------------------
+function remove_map_origin()
+	# Remove MAP_ORIGIN_X and MAP_ORIGIN_Y from the gmt.conf.0.subplot file
+	# The problem: GMT CLI when it creates the gmt.conf.0.subplot file, does not set MAP_ORIGIN_X and MAP_ORIGIN_Y
+	# but because we fiddle a lot with themes and make the classic mode behave like modern, we end up setting them
+	# and that has a drastic effect of burning permanently in the GMT_keyword_updated[] internal variable, AND THERE
+	# IS NO WAY TO UNSET things inside GMT_keyword_updated[] from externals. When gmt_begin() is called, the
+	# gmt.conf.0.subplot file is created and the MAP_ORIGIN_X and MAP_ORIGIN_Y are set. But this SCREWS the location
+	# of the colorbars when we have subplots because they all overlap each other. The only solution found is to remove
+	# the MAP_ORIGIN_X and MAP_ORIGIN_Y from the gmt.conf.0.subplot file.
+	# WARNING: If we ever implement the 'figure' case, this function will need to be modified to account for the
+	# figure number. As it is, the "0" in gmt.conf.0.subplot stands for figure 0.
+	API = unsafe_load(convert(Ptr{GMTAPI_CTRL}, G_API[]))
+	session_dir = unsafe_string(API.gwf_dir)
+	fname = session_dir * filesep * "gmt.conf.0.subplot"
+	!isfile(fname) && return
+	lines = readlines(fname)
+	filtered = filter(l -> !startswith(l, "MAP_ORIGIN_"), lines)
+	length(filtered) == length(lines) && return nothing		# Nothing to remove
+	open(fname, "w") do io
+		for l in filtered
+			println(io, l)
+		end
+	end
+	return nothing
 end

test/runtests.jl

@@ -133,7 +133,9 @@ using InteractiveUtils
 
 	println("	SEGY")
 	segy("", R="-35/6/0/30", J="x0.15i/-0.15i", D=0.35, C=8.0, F=:green, Q=(b=-1.2, x=0.1, y=0.1), S=:c, W=true, Vd=2);
+	segy!("", D=0.35, C=8.0, F=:green, Q=(b=-1.2, x=0.1, y=0.1), S=:c, W=true, Vd=2);
 	segyz("", R="-35/6/0/30/0/30", J="x0.15i/-0.15i", Jz="-0.15i", p=(175,5), D=0.35, C=8.0, F=:green, Q=(b=-1.2,), S="c/5", W=true, Vd=2);
+	segyz!("", Jz="-0.15i", p=(175,5), D=0.35, C=8.0, F=:green, Q=(b=-1.2,), S="c/5", W=true, Vd=2);
 	segy2grd("", R="-35/6/0/30", I=0.1, Vd=2);
 
 	#G = gmt("grdmath -R-15/15/-15/15 -I1 X Y HYPOT DUP 2 MUL PI MUL 8 DIV COS EXCH NEG 10 DIV EXP MUL =");