TeX output for UML diagrams [path]

[Ruslan Shevchenko <ruslan shevchenko kiev ua>]

Diar dia-rs :

0. Thanks for dia ;).

1. Small problem with printing UML diagram in TeX: TeX special symbols 
in names (such as #) are not escaped, as result TeX output
are not compiled by TeX.
So, I attach patch against dia-0.88.1

2. Are anybody know: what can cause invisability of some words in TeX 
diagrams ?


diff -udr dia-0.88.1/plug-ins/pstricks/render_pstricks.c 
dia-0.88.1.patched/plug-ins/pstricks/render_pstricks.c
--- dia-0.88.1/plug-ins/pstricks/render_pstricks.c      Mon Mar 26 04:05:23 2001
+++ dia-0.88.1.patched/plug-ins/pstricks/render_pstricks.c      Fri Jan  4 04:28:22 2002
@@ -45,6 +45,7 @@
 #include <string.h>
 #include <time.h>
 #include <math.h>
+#include <stdlib.h>
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -649,12 +650,89 @@
     fprintf(renderer->file, "\\fill[fillstyle=solid,fillcolor=diafillcolor,linecolor=diafillcolor]}\n");
 }
 
+/*
+ * return number of characters, needed to be added to length of resulted TeX
+ * output with char ch. 
+ * return 0 means, that we can do not touch ch for TeX,
+ * otherwise we must output prefix (setted in this function) and
+ * if replace is true -> output char ch itself.
+ *
+ * memory: note, that prefix is setted to static string.
+ */
+static int is_tex_escaped_symbol(char ch, 
+                                 char** prefix, 
+                                 int* replace)
+{
+ switch(ch) {
+   case '#':
+   case '$':
+   case '%':
+   case '&':
+   case '~':
+   case '_':
+   case '^':
+   case '\\':
+   case '{':
+   case '}':
+          *prefix="\\";
+          *replace=0;
+          return 1;
+   case '\xBB':   /* '<<' -> '{$\langle\!\langle$}' */
+          *prefix="{$\\langle\\!\\langle$}";
+          *replace=1;
+          return strlen(*prefix)-1;
+   case '\xAB':   /* '>>' -> '{$\rangle\!\rangle$}' */
+          *prefix="{$\\rangle\\!\\rangle$}";
+          *replace=1;
+          return strlen(*prefix)-1;
+   default:
+          return 0;
+ }
+}
+
+/**
+ * create string, in which TeX symbols are escaped by '\' symbol
+ * or substituted by tex control sequences.
+ * (example: #xxx -> \#xxx
+ * memory is allocated inside function, so client must free received pointer
+ **/
+static char* create_tex_escaped_string(const char* in_text)
+{
+ /* count number of symbols to escaped */
+ int extra_count = 0;
+ const char* in_cursor;
+ char* out_cursor;
+ char* out_text;
+ char* prefix;
+ int   replace=0;
+ for(in_cursor=in_text;*in_cursor; ++in_cursor) {
+   extra_count+=is_tex_escaped_symbol(*in_cursor,&prefix,&replace);
+ }
+ /* now alloc memory and print prefixed escaped string */
+ out_text = malloc(strlen(in_text)+extra_count+1);
+ out_cursor=out_text;
+ for(in_cursor=in_text;*in_cursor;) {
+   if (is_tex_escaped_symbol(*in_cursor,&prefix,&replace)) {
+     while(*prefix) *out_cursor++ = *prefix++;
+   }
+   if (!replace) {
+     *out_cursor++=*in_cursor++;
+   }else{
+     in_cursor++;
+   }
+ }
+ *out_cursor++='\0';
+ return out_text;
+}
+
 static void
 draw_string(RendererPSTRICKS *renderer,
            const char *text,
            Point *pos, Alignment alignment,
            Color *color)
 {
+    char* tex_escaped_text;
+
     set_line_color(renderer,color);
 
     fprintf(renderer->file,"\\rput");
@@ -668,7 +746,12 @@
        fprintf(renderer->file,"[r]");
        break;
     }
-    fprintf(renderer->file,"(%f,%f){\\scalebox{1 -1}{%s}}\n",pos->x, pos->y,text);
+    
+    tex_escaped_text=create_tex_escaped_string(text); 
+
+    fprintf(renderer->file,"(%f,%f){\\scalebox{1 -1}{%s}}\n",pos->x, pos->y,tex_escaped_text);
+
+    free(tex_escaped_text);
 }
 
 static void