[pango/pango2: 179/195] font description: Allow integer values for stretch

[Matthias Clasen <matthiasc src gnome org>]

commit a112ef3c238aba9d79df255d79eae26902849c04
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Feb 20 13:53:36 2022 -0500

    font description: Allow integer values for stretch
    
    And do approximate matching for stretch like we do
    for weight.

 pango/pango-font-description.c | 17 +++++++++--------
 pango/pango-font-description.h | 21 ++++++++++++---------
 2 files changed, 21 insertions(+), 17 deletions(-)
---
diff --git a/pango/pango-font-description.c b/pango/pango-font-description.c
index 89de07c9..86349d7d 100644
--- a/pango/pango-font-description.c
+++ b/pango/pango-font-description.c
@@ -758,7 +758,6 @@ pango_font_description_is_similar (const PangoFontDescription *a,
                                    const PangoFontDescription *b)
 {
   return a->variant == b->variant &&
-         a->stretch == b->stretch &&
          a->gravity == b->gravity;
 }
 
@@ -768,14 +767,16 @@ pango_font_description_compute_distance (const PangoFontDescription *a,
 {
   if (a->style == b->style)
     {
-      return abs((int)(a->weight) - (int)(b->weight));
+      return abs ((int)(a->weight) - (int)(b->weight)) +
+             abs ((int)(a->stretch) - (int)(b->stretch));
     }
   else if (a->style != PANGO_STYLE_NORMAL &&
            b->style != PANGO_STYLE_NORMAL)
     {
       /* Equate oblique and italic, but with a big penalty
        */
-      return 1000000 + abs ((int)(a->weight) - (int)(b->weight));
+      return 1000000 + abs ((int)(a->weight) - (int)(b->weight))
+                     + abs ((int)(a->stretch) - (int)(b->stretch));
     }
   else
     return G_MAXINT;
@@ -791,11 +792,11 @@ pango_font_description_compute_distance (const PangoFontDescription *a,
  * for @desc than those of @old_match are, or if @old_match is %NULL,
  * determines if @new_match is a match at all.
  *
- * Approximate matching is done for weight and style; other style attributes
- * must match exactly. Style attributes are all attributes other than family
- * and size-related attributes. Approximate matching for style considers
- * %PANGO_STYLE_OBLIQUE and %PANGO_STYLE_ITALIC as matches, but not as good
- * a match as when the styles are equal.
+ * Approximate matching is done for weight, stretch and style; other style
+ * attributes must match exactly. Style attributes are all attributes other
+ * than family and size-related attributes. Approximate matching for style
+ * considers %PANGO_STYLE_OBLIQUE and %PANGO_STYLE_ITALIC as matches, but
+ * not as good a match as when the styles are equal.
  *
  * Note that @old_match must match @desc.
  *
diff --git a/pango/pango-font-description.h b/pango/pango-font-description.h
index 21989e69..999a276c 100644
--- a/pango/pango-font-description.h
+++ b/pango/pango-font-description.h
@@ -130,17 +130,20 @@ typedef enum {
  *
  * An enumeration specifying the width of the font relative to other designs
  * within a family.
+ *
+ * Stretch is specified as a numeric value ranging from 500 to 2000.
+ * This enumeration simply provides some common, predefined values.
  */
 typedef enum {
-  PANGO_STRETCH_ULTRA_CONDENSED,
-  PANGO_STRETCH_EXTRA_CONDENSED,
-  PANGO_STRETCH_CONDENSED,
-  PANGO_STRETCH_SEMI_CONDENSED,
-  PANGO_STRETCH_NORMAL,
-  PANGO_STRETCH_SEMI_EXPANDED,
-  PANGO_STRETCH_EXPANDED,
-  PANGO_STRETCH_EXTRA_EXPANDED,
-  PANGO_STRETCH_ULTRA_EXPANDED
+  PANGO_STRETCH_ULTRA_CONDENSED =  500,
+  PANGO_STRETCH_EXTRA_CONDENSED =  625,
+  PANGO_STRETCH_CONDENSED       =  750,
+  PANGO_STRETCH_SEMI_CONDENSED  =  875,
+  PANGO_STRETCH_NORMAL          = 1000,
+  PANGO_STRETCH_SEMI_EXPANDED   = 1125,
+  PANGO_STRETCH_EXPANDED        = 1250,
+  PANGO_STRETCH_EXTRA_EXPANDED  = 1500,
+  PANGO_STRETCH_ULTRA_EXPANDED  = 2000
 } PangoStretch;
 
 /**