Screen size can be rotated using the "--orient=portrait" command-line option or "orient=portait" configuration file setting. This swaps the width and height values used for window or screen size.

docs/CHANGES.txt

@@ -22,6 +22,14 @@ $Id$
       it no longer shows 'success' pop-up that must be dismissed.)
       (Addresses SourceForge RFE #1680500)
 
+    * Screen size can be rotated using the "--orient=portrait" command-line
+      option or "orient=portait" configuration file setting.  This swaps
+      the width and height values used for window or screen size.
+      (e.g., "tuxpaint --fullscreen --1024x786 --orient=portrait" will
+      run Tux Paint in 768x1024 mode.)  Useful for tablet PCs.
+      Note: override previously-set option with "--orient=landscape" or
+      "orient=landscape".
+
   * Tool Improvements:
     ------------------
     * Input Method Framework, with implementations of Korean (Hangul 2-Bul)

docs/OPTIONS.txt

@@ -93,6 +93,12 @@ Windows Users
                 * 768x1024
                 * 1600x1200
 
+     orient=portrait
+
+             Swaps the width/height options given to Tux Paint, useful for
+             rotating the window on portait displays, such as a tablet PC
+             that's in tablet orientation.
+
      native=yes
 
              When running Tux Paint in fullscreen mode, this assumes the
@@ -549,6 +555,7 @@ Windows Users
 
        --fullscreen
        --WIDTHxHEIGHT
+       --orient=portrait
        --native
        --startblank
        --nosound
@@ -583,6 +590,7 @@ Windows Users
 
        --windowed
        --800x600
+       --orient=landscape
        --startlast
        --sound
        --quit

docs/html/OPTIONS.html

@@ -131,6 +131,13 @@ New Breed Software</p>
     </p>
   </dd>
 
+  <dt><code><b>orient=portrait</b></code></dt>
+  <dd>
+    <p>Swaps the width/height options given to Tux&nbsp;Paint, useful for
+    rotating the window on portait displays, such as a tablet&nbsp;PC that's
+    in tablet orientation.
+  </dd>
+
   <dt><code><b>native=yes</b></code></dt>
   <dd>
     <p>When running <i>Tux&nbsp;Paint</i> in fullscreen mode, this
@@ -867,6 +874,7 @@ New Breed Software</p>
     <dt><code><b>
     --fullscreen<br>
     --<i>WIDTH</i>x<i>HEIGHT</i><br>
+    --orient=portrait<br>
     --native<br>
     --startblank<br>
     --nosound<br>
@@ -904,6 +912,7 @@ New Breed Software</p>
     <dt><code><b>
     --windowed<br>
     --800x600<br>
+    --orient=landscape<br>
     --startlast<br>
     --sound<br>
     --quit<br>

src/tuxpaint.c

@@ -808,7 +808,7 @@ static int fullscreen, native_screensize, disable_quit, simple_shapes,
   no_button_distinction,
   mirrorstamps, disable_stamp_controls, disable_save, ok_to_use_lockfile,
   alt_print_command_default, scrolling = 0,
-  start_blank, autosave_on_quit;
+  start_blank, autosave_on_quit, rotate_orientation;
 static int want_alt_printcommand;
 static int starter_mirrored, starter_flipped, starter_personal;
 static int recording, playing;
@@ -5312,7 +5312,7 @@ static void show_usage(FILE * f, char *prg)
 	  "Usage: %s {--usage | --help | --version | --copying}\n"
 	  "\n"
 	  "  %s [--windowed | --fullscreen]\n"
-	  "  %s [--WIDTHxHEIGHT | --native]\n"
+	  "  %s [--WIDTHxHEIGHT | --native]   [--orient=ORIENTATION]\n"
 	  "  %s [--startblank | --startlast ]\n"
 	  "  %s [--sound | --nosound]         [--quit | --noquit]\n"
 	  "  %s [--print | --noprint]         [--complexshapes | --simpleshapes]\n"
@@ -6050,6 +6050,7 @@ static void setup(int argc, char *argv[])
   fullscreen = 0;
 #endif
   native_screensize = 0;
+  rotate_orientation = 0;
   noshortcuts = 0;
   dont_do_xor = 0;
   keymouse = 0;
@@ -6283,6 +6284,14 @@ static void setup(int argc, char *argv[])
     {
       native_screensize = 1;
     }
+    else if (strcmp(argv[i], "--orient=portrait") == 0)
+    {
+      rotate_orientation = 1;
+    }
+    else if (strcmp(argv[i], "--orient=landscape") == 0)
+    {
+      rotate_orientation = 0;
+    }
     else if (strcmp(argv[i], "--nooutlines") == 0)
     {
       dont_do_xor = 1;
@@ -6909,6 +6918,23 @@ static void setup(int argc, char *argv[])
     SDL_ShowCursor (SDL_DISABLE);
 
 
+  /* Deal with orientation rotation option */
+
+  if (rotate_orientation)
+  {
+    if (native_screensize && fullscreen)
+    {
+      fprintf(stderr, "Warning: Asking for native screen size overrides request to rotate orientation.\n");
+    }
+    else
+    {
+      int tmp;
+      tmp = WINDOW_WIDTH;
+      WINDOW_WIDTH = WINDOW_HEIGHT;
+      WINDOW_HEIGHT = tmp;
+    }
+  }
+
   /* Deal with 'native' screen size option */
 
   if (native_screensize)