PATCH: --size option for PNG export

["W. Borgert" <debacle debian org>]

I resend this in case the original patch got lost.  If
someone has an idea how to implement distortion if both
width and heigth are given, give me a hint.

Please apply!

Cheers,
-- 
W. Borgert <debacle@debian.org>
diff -ruN dia/app/app_procs.c dia.new/app/app_procs.c
--- dia/app/app_procs.c	2003-11-25 23:56:45.000000000 +0000
+++ dia.new/app/app_procs.c	2003-11-25 23:56:29.000000000 +0000
@@ -85,7 +85,8 @@
 static gboolean
 handle_initial_diagram(const char *input_file_name, 
 		       const char *export_file_name,
-		       const char *export_file_format);
+		       const char *export_file_format,
+		       const char *size);
 
 static void create_user_dirs(void);
 static PluginInitResult internal_plugin_init(PluginInfo *info);
@@ -150,10 +151,12 @@
 
 /** Convert infname to outfname, using input filter inf and export filter
  * ef.  If either is null, try to guess them.
+ * size might be NULL.
  */
 gboolean
 do_convert(const char *infname, 
-	   const char *outfname, DiaExportFilter  *ef)
+	   const char *outfname, DiaExportFilter *ef,
+	   const char *size)
 {
   DiaImportFilter *inf;
   DiagramData *diagdata = NULL;
@@ -188,6 +191,9 @@
             argv0,infname);
             exit(1);
   }
+  /* is user_data supposed to work that way? */
+  if (size)
+    ef->user_data = (void *) size;
   ef->export(diagdata, outfname, infname, ef->user_data);
   /* if (!quiet) */ fprintf(stdout,
                       _("%s --> %s\n"),
@@ -217,7 +223,8 @@
 static gboolean
 handle_initial_diagram(const char *in_file_name, 
 		       const char *out_file_name,
-		       const char *export_file_format) {
+		       const char *export_file_format,
+		       const char *size) {
   DDisplay *ddisp = NULL;
   Diagram *diagram = NULL;
   gboolean made_conversions = FALSE;
@@ -238,10 +245,12 @@
       export_file_name = build_output_file_name(in_file_name,
 						ef->extensions[0]);
     }
-    made_conversions |= do_convert(in_file_name, (out_file_name != NULL?out_file_name:export_file_name), ef);
+    made_conversions |= do_convert(in_file_name,
+      (out_file_name != NULL?out_file_name:export_file_name), ef, size);
     g_free(export_file_name);
   } else if (out_file_name) {
-    made_conversions |= do_convert(in_file_name, out_file_name, NULL);
+    made_conversions |= do_convert(in_file_name, out_file_name, NULL,
+				   size);
   } else {
     if (g_file_test(in_file_name, G_FILE_TEST_EXISTS)) {
       diagram = diagram_load (in_file_name, NULL);
@@ -307,6 +316,7 @@
 #endif
   char *export_file_name = NULL;
   char *export_file_format = NULL;
+  char *size = NULL;
   gboolean made_conversions = FALSE;
 
 #ifdef HAVE_POPT
@@ -329,6 +339,8 @@
     {"export-to-format",'t', POPT_ARG_STRING, NULL /* &export_file_format */,
      0, export_format_string, N_("FORMAT")
     },
+    {"size", 's', POPT_ARG_STRING, NULL, 0,
+     N_("Export graphics size"), N_("WxH")},
     {"nosplash", 'n', POPT_ARG_NONE, &nosplash, 0,
      N_("Don't show the splash screen"), NULL },
     {"credits", 'c', POPT_ARG_NONE, &credits, 0,
@@ -345,6 +357,7 @@
 #ifdef HAVE_POPT
   options[0].arg = &export_file_name;
   options[1].arg = &export_file_format;
+  options[2].arg = &size;
 #endif
 
   argv0 = (argc > 0) ? argv[0] : "(none)";
@@ -525,10 +538,11 @@
 #ifdef HAVE_POPT
       while (poptPeekArg(poptCtx)) {
           char *in_file_name = (char *)poptGetArg(poptCtx);
-	  
+
 	  made_conversions |= handle_initial_diagram(in_file_name,
 						     export_file_name,
-						     export_file_format);
+						     export_file_format,
+						     size);
       }
       poptFreeContext(poptCtx);
 #else
@@ -549,11 +563,18 @@
                   export_file_name = argv[i];
                   continue;
               }
+          } else if (0 == strcmp(argv[i],"-s")) {
+              if (i < (argc-1)) {
+                  i++;
+                  size = argv[i];
+                  continue;
+              }
           }
           
 	  made_conversions |= handle_initial_diagram(in_file_name,
 						     export_file_name,
-						     export_file_format);
+						     export_file_format,
+						     size);
       }
 #endif
   }
@@ -725,3 +746,19 @@
   return DIA_PLUGIN_INIT_OK;
 }
 
+/* parses a string of the form "[0-9]*x[0-9]*" and transforms it into
+   two long values width and height. */
+void
+parse_size(gchar *size, long *width, long *height)
+{
+  if (size) {
+    gchar** array = g_strsplit(size, "x", 3);
+    *width  = (array[0])? strtol(array[0], NULL, 10): 0;
+    *height = (array[1])? strtol(array[1], NULL, 10): 0;
+    g_strfreev(array);
+  }
+  else {
+    *width  = 0;
+    *height = 0;
+  }
+}
diff -ruN dia/app/app_procs.h dia.new/app/app_procs.h
--- dia/app/app_procs.h	2003-11-25 23:56:45.000000000 +0000
+++ dia.new/app/app_procs.h	2003-11-25 23:56:29.000000000 +0000
@@ -25,7 +25,8 @@
 int app_is_embedded(void);
 
 gboolean do_convert(const char *infname,
-		    const char *outfname, DiaExportFilter *ef);
+		    const char *outfname, DiaExportFilter *ef,
+		    const char *size);
 char *build_output_file_name(const char *infname, const char *format);
 
 void app_splash_init(const gchar* name);
@@ -33,4 +34,8 @@
 
 gboolean app_is_interactive(void);
 
+/* parses a string of the form "[0-9]*x[0-9]*" and transforms it into
+   two long values width and height. */
+void parse_size(gchar *size, long *width, long *height);
+
 #endif /* APP_PROCS_H */
diff -ruN dia/app/diaconv.c dia.new/app/diaconv.c
--- dia/app/diaconv.c	2003-11-25 23:56:45.000000000 +0000
+++ dia.new/app/diaconv.c	2003-11-25 23:56:29.000000000 +0000
@@ -213,7 +213,7 @@
       export_file_name = build_output_file_name(in_file_name,
                                                 export_file_format);
       g_message("export_file_name = %s",export_file_name);
-      do_convert(in_file_name,export_file_name);
+      do_convert(in_file_name, export_file_name, NULL);
       g_free(export_file_name);
       in_file_name = poptGetArg(poptCtx);
     }
@@ -226,7 +226,7 @@
               argv[0]);
       exit(1);
     }
-    do_convert(in_file_name,export_file_name);
+    do_convert(in_file_name, export_file_name, NULL);
   }
   exit(0);
 }
diff -ruN dia/app/export_png.c dia.new/app/export_png.c
--- dia/app/export_png.c	2003-11-25 23:56:45.000000000 +0000
+++ dia.new/app/export_png.c	2003-11-25 23:56:29.000000000 +0000
@@ -48,6 +48,7 @@
 struct png_callback_data {
   DiagramData *data;
   gchar *filename;
+  gchar *size;			/* for command line option --size */
 };
 
 /* Static data.  When the dialog is not reentrant, you could have all data
@@ -75,6 +76,7 @@
   guint32 width, height, band, row, i;
   real band_height;
   guint32 imagewidth, imageheight;
+  long req_width, req_height;
   real imagezoom;
 
   FILE *fp;
@@ -93,8 +95,24 @@
     imagewidth = gtk_spin_button_get_value_as_int(export_png_width_entry);
     imageheight = gtk_spin_button_get_value_as_int(export_png_height_entry);
   } else {
-    imagewidth = width;
-    imageheight = height;
+    if (cbdata && cbdata->size) {
+      float ratio = (float) width/(float) height;
+
+      parse_size(cbdata->size, &req_width, &req_height);
+      if (req_width && !req_height) {
+	imagewidth  = req_width;
+	imageheight = req_width / ratio;
+      } else if (req_height && !req_width) {
+	imagewidth  = req_height * ratio;
+	imageheight = req_height;
+      } else if (req_width && req_height) {
+	imagewidth  = req_width;
+	imageheight = req_height;
+      }
+    } else {
+      imagewidth  = width;
+      imageheight = height;
+    }
   }
 
   imagezoom = ((real)imageheight/height) * DPCM * data->paper.scaling;
@@ -147,8 +165,24 @@
     imagewidth = gtk_spin_button_get_value_as_int(export_png_width_entry);
     imageheight = gtk_spin_button_get_value_as_int(export_png_height_entry);
   } else {
-    imagewidth = width;
-    imageheight = height;
+    if (cbdata && cbdata->size) {
+      float ratio = (float) width/(float) height;
+
+      parse_size(cbdata->size, &req_width, &req_height);
+      if (req_width && !req_height) {
+	imagewidth  = req_width;
+	imageheight = req_width / ratio;
+      } else if (req_height && !req_width) {
+	imagewidth  = req_height * ratio;
+	imageheight = req_height;
+      } else if (req_width && req_height) {
+	imagewidth  = req_width;
+	imageheight = req_height;
+      }
+    } else {
+      imagewidth  = width;
+      imageheight = height;
+    }
   }
   band = MIN(imageheight, BAND_HEIGHT);
 
@@ -251,7 +285,7 @@
      returns before the callback is called.  Must be freed by the
      final callbacks. */
   struct png_callback_data *cbdata = 
-    (struct png_callback_data *)g_malloc(sizeof(struct png_callback_data));
+    (struct png_callback_data *) g_new0(struct png_callback_data, 1);
   Rectangle *ext = &data->extents;
   guint32 width, height;
 
@@ -310,6 +344,7 @@
     /* Show the whole thing */
     gtk_widget_show_all(export_png_dialog);
   } else {
+    cbdata->size = (gchar *) user_data;
     export_png_ok(NULL, cbdata);
   }
 }
diff -ruN dia/doc/en/dia.dbk dia.new/doc/en/dia.dbk
--- dia/doc/en/dia.dbk	2003-11-26 00:11:15.000000000 +0000
+++ dia.new/doc/en/dia.dbk	2003-11-26 00:13:06.000000000 +0000
@@ -6,7 +6,8 @@
   <refentryinfo>
     <copyright>
       <year>1999</year>
-      <holder>Fredrik Hallenberg</holder>
+      <year>2003</year>
+      <holder>Fredrik Hallenberg, W. Borgert</holder>
     </copyright>
     <date>1999-07-03</date>
     <authorgroup>
@@ -24,6 +25,12 @@
     <revhistory>
       <revision>
 	<revnumber>2</revnumber>
+	<date>2003-11-26</date>
+	<authorinitials>WB</authorinitials>
+	<revremark>added --size option</revremark>
+      </revision>
+      <revision>
+	<revnumber>2</revnumber>
 	<date>2003-10-16</date>
 	<authorinitials>WB</authorinitials>
 	<revremark>added different EPS variants and section on
@@ -70,6 +77,10 @@
 
       <arg><option>--nosplash</option></arg>
 
+      <arg><option>-s <replaceable>WxH</replaceable></option></arg>
+
+      <arg><option>--size=<replaceable>WxH</replaceable></option></arg>
+
       <arg><option>-t <replaceable>FORMAT</replaceable></option></arg>
 
       <arg><option>--export-to-format=<replaceable>FORMAT</replaceable></option></arg>
@@ -136,6 +147,23 @@
 	</listitem>
       </varlistentry>
       <varlistentry>
+	<term><option>-s <replaceable>WxH</replaceable></option>
+	  <option>--size=<replaceable>WxH</replaceable></option></term>
+	<listitem>
+	  <para>Export loaded file in decimal given width and/or
+	  height.  It is allowed to only select width or height.
+	  E.g. <option>--size=<replaceable>520x</replaceable></option>
+	  exports an image that is 520 pixels wide, while
+	  <option>--size=<replaceable>x900</replaceable></option>
+	  exports an image of 900 pixels height.</para>
+
+	  <note>
+	    <para>This option is currently only implemented for the
+	    PNG export filter.</para>
+	  </note>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
 	<term><option>-t <replaceable>FORMAT</replaceable></option>
 	  <option>--export-to-format=<replaceable>FORMAT</replaceable></option></term>
 	<listitem>