[goffice] Style: activate font theming of graphs.

[Morten Welinder <mortenw src gnome org>]

commit 216d1281d49dd94d538c63102f775b20a11e1aa2
Author: Morten Welinder <terra gnome org>
Date:   Mon Feb 16 18:23:44 2015 -0500

    Style: activate font theming of graphs.

 ChangeLog                |   11 ++++++++
 NEWS                     |    1 +
 goffice/utils/go-style.c |   64 +++++++++++++++++++++++++++------------------
 3 files changed, 50 insertions(+), 26 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 9329d43..3b20c17 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2015-02-16  Morten Welinder  <terra gnome org>
+
+       * goffice/utils/go-style.c (cb_font_changed): Set auto_font.
+       (go_style_apply_theme): Apply font theming.
+       (go_style_font_sax_save): Only save font when not auto.
+       (go_style_sax_load_font): Be fairly smart about reading files
+       created prior to this fix.
+       (go_style_is_auto): Include auto_font and auto_color.
+       (go_style_line_sax_save, go_style_gradient_sax_save)
+       (go_style_text_layout_sax_save): Use sufficient precision.
+
 2015-02-14  Morten Welinder  <terra gnome org>
 
        * goffice/utils/go-line.c (go_arrow_equal): New function.
diff --git a/NEWS b/NEWS
index 80e1b57..9e051a0 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ Morten:
        * Fix problem with linear solver.
        * Add arrow selector widget.
        * Fix rendering of dotted lines.  [#744419]
+       * Activate font part of graph theming.
 
 --------------------------------------------------------------------------
 goffice 0.10.20:
diff --git a/goffice/utils/go-style.c b/goffice/utils/go-style.c
index 5ad7736..ce96e68 100644
--- a/goffice/utils/go-style.c
+++ b/goffice/utils/go-style.c
@@ -901,6 +901,7 @@ cb_font_changed (GOFontSel *fs, PangoAttrList *list,
        g_slist_foreach (extra_attrs, (GFunc)pango_attribute_destroy, NULL);
        g_slist_free (extra_attrs);
        pango_attr_iterator_destroy (iter);
+       state->style->font.auto_font = (font == state->default_style->font.font);
        go_style_set_font (state->style, font);
        set_style (state);
 }
@@ -1281,17 +1282,13 @@ go_style_apply_theme (GOStyle *dst, GOStyle const *src, GOStyleFlag fields)
                if (dst->font.auto_color)
                        dst->font.color = src->font.color;
 
-#if 0
-               /*
-                * Fonts are not themed until we have some sort of auto
-                * mechanism stronger than 'auto_size'
-                */
-               if (src->font.font != NULL)
-                       go_font_ref (src->font.font);
-               if (dst->font.font != NULL)
-                       go_font_unref (dst->font.font);
-               dst->font = src->font;
-#endif
+               if (dst->font.auto_font) {
+                       if (src->font.font != NULL)
+                               go_font_ref (src->font.font);
+                       if (dst->font.font != NULL)
+                               go_font_unref (dst->font.font);
+                       dst->font = src->font;
+               }
        }
 }
 
@@ -1429,7 +1426,7 @@ go_style_line_sax_save (GsfXMLOut *output, char const *name,
 
        gsf_xml_out_add_bool (output, "auto-width", line->auto_width);
        if (!line->auto_width)
-               gsf_xml_out_add_float (output, "width", line->width, 6);
+               gsf_xml_out_add_float (output, "width", line->width, -1);
 
        gsf_xml_out_add_bool (output, "auto-color", line->auto_color);
        if (!line->auto_color)
@@ -1448,7 +1445,7 @@ go_style_gradient_sax_save (GsfXMLOut *output, GOStyle const *style)
                style->fill.pattern.back);
        if (style->fill.gradient.brightness >= 0.)
                gsf_xml_out_add_float (output, "brightness",
-                       style->fill.gradient.brightness, 6);
+                       style->fill.gradient.brightness, -1);
        else
                go_xml_out_add_color (output, "end-color",
                        style->fill.pattern.fore);
@@ -1534,8 +1531,6 @@ go_style_marker_sax_save (GsfXMLOut *output, GOStyle const *style)
 static void
 go_style_font_sax_save (GsfXMLOut *output, GOStyle const *style)
 {
-       char *str;
-
        gsf_xml_out_start_element (output, "font");
 
        gsf_xml_out_add_bool (output, "auto-color", style->font.auto_color);
@@ -1543,10 +1538,11 @@ go_style_font_sax_save (GsfXMLOut *output, GOStyle const *style)
                go_xml_out_add_color (output, "color", style->font.color);
 
        gsf_xml_out_add_bool (output, "auto-font", style->font.auto_font);
-       /* Unconditionally save font; theme support for fonts is incomplete */
-       str = go_font_as_str (style->font.font);
-       gsf_xml_out_add_cstr (output, "font", str);
-       g_free (str);
+       if (!style->font.auto_font) {
+               char *str = go_font_as_str (style->font.font);
+               gsf_xml_out_add_cstr (output, "font", str);
+               g_free (str);
+       }
 
        gsf_xml_out_add_bool (output, "auto-scale", style->font.auto_scale);
 
@@ -1558,7 +1554,7 @@ go_style_text_layout_sax_save (GsfXMLOut *output, GOStyle const *style)
 {
        gsf_xml_out_start_element (output, "text_layout");
        if (!style->text_layout.auto_angle)
-               gsf_xml_out_add_float (output, "angle", style->text_layout.angle, 6);
+               gsf_xml_out_add_float (output, "angle", style->text_layout.angle, -1);
        gsf_xml_out_end_element (output);
 }
 
@@ -1704,6 +1700,7 @@ go_style_sax_load_font (GsfXMLIn *xin, xmlChar const **attrs)
 {
        GOStyle *style = GO_STYLE (xin->user_state);
        gboolean seen_auto_color = FALSE, seen_color = FALSE;
+       gboolean seen_auto_font = FALSE, seen_font = FALSE;
 
        for (; attrs != NULL && attrs[0] && attrs[1] ; attrs += 2) {
                if (attr_eq (attrs[0], "color")) {
@@ -1711,6 +1708,8 @@ go_style_sax_load_font (GsfXMLIn *xin, xmlChar const **attrs)
                        go_color_from_str (attrs[1], &style->font.color);
                } else if (bool_sax_prop ("auto-color", attrs[0], attrs[1], &style->font.auto_color)) {
                        seen_auto_color = TRUE;
+               } else if (bool_sax_prop ("auto-font", attrs[0], attrs[1], &style->font.auto_font)) {
+                       seen_auto_font = TRUE;
                } else if (attr_eq (attrs[0], "font")) {
                        PangoFontDescription *desc = pango_font_description_from_string (attrs[1]);
                        if (desc != NULL) {
@@ -1718,6 +1717,7 @@ go_style_sax_load_font (GsfXMLIn *xin, xmlChar const **attrs)
                                        pango_font_description_set_family_static (desc, "Sans");
                                go_style_set_font_desc (style, desc);
                        }
+                       seen_font = TRUE;
                } else if (bool_sax_prop ("auto-scale", attrs[0], attrs[1], &style->font.auto_scale))
                        ;
        }
@@ -1729,6 +1729,17 @@ go_style_sax_load_font (GsfXMLIn *xin, xmlChar const **attrs)
                 */
                style->font.auto_color = (style->font.color == GO_COLOR_BLACK);
        }
+
+       if (seen_font && seen_auto_font && style->font.auto_font) {
+               GOFont const *def = go_font_new_by_index (0);
+               /*
+                * Pre-0.10.21 lacked the font styling.  We were always saving a font and
+                * always saving auto-font=TRUE.  Since we weren't actually applying any
+                * font theming, the default is font 0 (aka "Sans 8").
+                */
+               style->font.auto_font = (style->font.font == def);
+               go_font_unref (def);
+       }
 }
 
 static void
@@ -1948,11 +1959,12 @@ go_style_clear_auto (GOStyle *style)
 gboolean
 go_style_is_auto (GOStyle *style)
 {
-       return style->marker.auto_shape && style->marker.auto_outline_color &&
-              style->marker.auto_fill_color && style->line.auto_dash &&
-              style->line.auto_color && style->fill.auto_type &&
-              style->fill.auto_fore && style->fill.auto_back &&
-              style->font.auto_scale && style->text_layout.auto_angle;
+       return (style->marker.auto_shape && style->marker.auto_outline_color &&
+               style->marker.auto_fill_color && style->line.auto_dash &&
+               style->line.auto_color && style->fill.auto_type &&
+               style->fill.auto_fore && style->fill.auto_back &&
+               style->font.auto_scale && style->font.auto_color && style->font.auto_font &&
+               style->text_layout.auto_angle);
 }
 
 /**
@@ -2003,7 +2015,7 @@ go_style_set_font_desc (GOStyle *style, PangoFontDescription *desc)
 {
        g_return_if_fail (GO_IS_STYLE (style));
 
-       go_style_set_font (go_font_new_by_desc (desc));
+       go_style_set_font (style, go_font_new_by_desc (desc));
 }
 
 /**