WIP New "--uifont" option to specify UI font

If not specified, or "default" is specified (e.g., to override
a higher-up config file setting), it will fallback to what we
have #define'd in fonts.h as PANGO_DEFAULT_FONT, "DejaVu Sans".

It appears to fallback to this (or a reasonable fascimile) if
the font specified by the "uifont" option doesn't exist
(e.g., "tuxpaint --uifont=ABCD1234").

For https://sourceforge.net/p/tuxpaint/feature-requests/146/

docs/CHANGES.txt

@@ -49,6 +49,11 @@ https://tuxpaint.org/
       Closes https://sourceforge.net/p/tuxpaint/feature-requests/236/
       Bill Kendrick <bill@newbreedsoftware.com>
 
+    * WIP Ability to specify a font for Tux Paint's UI (button labels,
+      dialog boxes, Tux tip text at the bottom).
+      Closes https://sourceforge.net/p/tuxpaint/feature-requests/146/
+      Bill Kendrick <bill@newbreedsoftware.com>
+
   * Bug Fixes:
     ----------
     * In some window size / button size combinations, Eraser

src/fonts.h

@@ -19,7 +19,7 @@
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   (See COPYING.txt)
 
-  Last updated: April 30, 2023
+  Last updated: May 29, 2023
 */
 
 #ifndef FONTS_H
@@ -39,8 +39,11 @@
 #include "SDL_ttf.h"
 #include "SDL2_Pango.h"
 
+/* UI font, which as of 0.9.31, can be overridden by "uifont"
+   setting (also, this will be used if "uifont=default" is specified,
+   e.g. to override a config. file option using a command-line option) */
+
 #define PANGO_DEFAULT_FONT "DejaVu Sans"
-//#define PANGO_DEFAULT_FONT "OpenDyslexicAlta"
 
 #include "compiler.h"
 

src/parse.gperf

@@ -161,6 +161,7 @@ startblank,          POSBOOL(start_blank)
 startlast,           NEGBOOL(start_blank)
 sysconfig,           POSBOOL(parsertmp_sysconfig)
 sysfonts,            NEGBOOL(no_system_fonts)
+uifont,              MULTI(tp_ui_font)
 uppercase,           POSBOOL(only_uppercase)
 usage,               IMM(usage)
 verbose-version,     IMM(verbose_version)

src/parse.h

@@ -36,6 +36,7 @@ struct cfginfo
   const char *native_screensize;
   const char *new_colors_last;
   const char *no_button_distinction;
+  const char *tp_ui_font;
   const char *no_fancy_cursors;
   const char *no_system_fonts;
   const char *noshortcuts;

src/tuxpaint-completion.bash

@@ -53,6 +53,7 @@ _tuxpaint()
                         --newcolorsfirst --newcolorslast \
                         --colorsrows=1 --colorsrows=2 \
                         --colorsrows=3 \
+			--uifont --uifont=default \
 			--sysfonts --nosysfonts \
 			--nostampcontrols --stampcontrols \
 			--nostamprotation --stamprotation \

src/tuxpaint.c

@@ -586,6 +586,7 @@ int iswprint(wchar_t wc)
 
 #include "compiler.h"
 
+char * tp_ui_font = NULL;
 
 /* Convert floats to fractions between (min/max) and ((max-min)/max)
    (anything with smaller resolution will round up or down) */
@@ -8052,6 +8053,7 @@ void show_usage(int exitcode)
           " Languages:\n"
           "  [--lang LANGUAGE | --locale LOCALE | --lang help]\n"
           "  [--mirrorstamps | --dontmirrorstamps]\n"
+          "  [--uifont \"FONT NAME\" | --uifont default]\n"
           "  [--sysfonts | --nosysfonts]\n"
           "  [--currentlocalefont | --alllocalefonts]\n"
           "\n"
@@ -9283,7 +9285,7 @@ static int generate_fontconfig_cache_real(void)
 
   DEBUG_PRINTF("-- Hello from generate_fontconfig_cache() (thread # %d)\n", SDL_ThreadID());
 
-  tmp_font = TuxPaint_Font_OpenFont(PANGO_DEFAULT_FONT, NULL, 12);
+  tmp_font = TuxPaint_Font_OpenFont(PANGO_DEFAULT_FONT, NULL, 12); /* always just using the default font for the purpose of getting FontConfig to generate its cache */
 
   if (tmp_font != NULL)
   {
@@ -27875,6 +27877,23 @@ static void setup_config(char *argv[])
     tmpcfg.parsertmp_locale = NULL;
   button_label_y_nudge = setup_i18n(tmpcfg.parsertmp_lang, tmpcfg.parsertmp_locale, &num_wished_langs);
 
+  if (tmpcfg.tp_ui_font)
+  {
+    if (strcmp(tmpcfg.tp_ui_font, "default") == 0)
+    {
+      printf/*DEBUG_PRINTF*/("UI font will be default: %s\n", PANGO_DEFAULT_FONT);
+      tp_ui_font = strdup(PANGO_DEFAULT_FONT);
+    }
+    else
+    {
+      tp_ui_font = strdup(tmpcfg.tp_ui_font);
+      printf/*DEBUG_PRINTF*/("UI font will be: %s\n", tp_ui_font);
+    }
+  }
+  else
+  {
+    tp_ui_font = strdup(PANGO_DEFAULT_FONT);
+  }
 
   /* FIXME: most of this is not required before starting the font scanner */
 
@@ -29311,8 +29330,8 @@ static void setup(void)
 #endif
 
 
-  medium_font = TuxPaint_Font_OpenFont(PANGO_DEFAULT_FONT,
+  medium_font = TuxPaint_Font_OpenFont(tp_ui_font,
-                                       DATA_PREFIX "fonts/default_font.ttf",
+                                       DATA_PREFIX "fonts/default_font.ttf", /* FIXME: Does this matter any more? -bjk 2023.05.29 */
                                        (18 - (only_uppercase * 3)) * button_scale);
 
   if (medium_font == NULL)
@@ -29654,8 +29673,9 @@ static void setup(void)
 
   /* Load system fonts: */
 
-  large_font = TuxPaint_Font_OpenFont(PANGO_DEFAULT_FONT,
+  large_font = TuxPaint_Font_OpenFont(tp_ui_font,
-                                      DATA_PREFIX "fonts/default_font.ttf", (30 - (only_uppercase * 3)) * button_scale);
+                                      DATA_PREFIX "fonts/default_font.ttf", /* FIXME: Does this matter any more? -bjk 2023.05.29 */
+                                      (30 - (only_uppercase * 3)) * button_scale);
 
   if (large_font == NULL)
   {
@@ -29669,7 +29689,8 @@ static void setup(void)
   }
 
 
-  small_font = TuxPaint_Font_OpenFont(PANGO_DEFAULT_FONT, DATA_PREFIX "fonts/default_font.ttf",
+  small_font = TuxPaint_Font_OpenFont(tp_ui_font,
+                                      DATA_PREFIX "fonts/default_font.ttf", /* FIXME: Does this matter any more? -bjk 2023.05.29 */
 #ifdef __APPLE__
                                       (12 - (only_uppercase * 2)) * button_scale
 #else