[dia] svg: support multiplicative opacity

[Hans Breuer <hans src gnome org>]

commit 2f79a3f71345125c7fb1b71503678fa3113d5e4e
Author: Hans Breuer <hans breuer org>
Date:   Sun Jul 28 16:30:12 2013 +0200

    svg: support multiplicative opacity

 lib/dia_svg.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)
---
diff --git a/lib/dia_svg.c b/lib/dia_svg.c
index e9179bd..62b933d 100644
--- a/lib/dia_svg.c
+++ b/lib/dia_svg.c
@@ -431,6 +431,13 @@ dia_svg_parse_style(xmlNodePtr node, DiaSvgStyle *s, real user_scale)
       } else if (!strncmp("fill-opacity:", ptr, 13)) {
        ptr += 13;
        s->fill_opacity = g_ascii_strtod(ptr, &ptr);
+      } else if (!strncmp("opacity", ptr, 7)) {
+       real opacity;
+        ptr += 7;
+       opacity = g_ascii_strtod(ptr, &ptr);
+       /* multiplicative effect of opacity */
+       s->stroke_opacity *= opacity;
+       s->fill_opacity *= opacity;
       } else if (!strncmp("stroke-linecap:", ptr, 15)) {
        ptr += 15;
        while (ptr[0] != '\0' && g_ascii_isspace(ptr[0])) ptr++;
@@ -509,6 +516,14 @@ dia_svg_parse_style(xmlNodePtr node, DiaSvgStyle *s, real user_scale)
   /* ugly svg variations, it is allowed to give style properties without
    * the style attribute, i.e. direct attributes
    */
+  str = xmlGetProp(node, (const xmlChar *)"opacity");
+  if (str) {
+    real opacity = g_ascii_strtod((char *) str, NULL);
+    /* multiplicative effect of opacity */
+    s->stroke_opacity *= opacity;
+    s->fill_opacity *= opacity;
+    xmlFree(str);
+  }
   str = xmlGetProp(node, (const xmlChar *)"fill");
   if (str) {
     if (!_parse_color (&s->fill, (char *) str))