[clutter/clutter-1.8] backend: Fix em computation for non-absolute fonts

[Emmanuele Bassi <ebassi src gnome org>]

commit 85a466268360ad007de90e34b24fa0f56692eaa8
Author: Emmanuele Bassi <ebassi linux intel com>
Date:   Mon Dec 5 11:43:48 2011 +0000

    backend: Fix em computation for non-absolute fonts
    
    If a font description is not set to have an absolute size then we were
    using the wrong transformation for points to device units.
    (cherry picked from commit 158245fda31e7adad38aa49e4c12efcad0e326e0)
    
    Signed-off-by: Emmanuele Bassi <ebassi linux intel com>

 clutter/clutter-backend.c |    8 ++------
 1 files changed, 2 insertions(+), 6 deletions(-)
---
diff --git a/clutter/clutter-backend.c b/clutter/clutter-backend.c
index 8267544..db0a637 100644
--- a/clutter/clutter-backend.c
+++ b/clutter/clutter-backend.c
@@ -155,14 +155,10 @@ get_units_per_em (ClutterBackend       *backend,
       if (is_absolute)
         font_size = (gdouble) pango_size / PANGO_SCALE;
       else
-        font_size = (gdouble) pango_size / PANGO_SCALE
-                  * dpi
-                  / 96.0f;
+        font_size = dpi * ((gdouble) pango_size / PANGO_SCALE) / 72.0f;
 
       /* 10 points at 96 DPI is 13.3 pixels */
-      units_per_em = (1.2f * font_size)
-                   * dpi
-                   / 96.0f;
+      units_per_em = (1.2f * font_size) * dpi / 96.0f;
     }
   else
     units_per_em = -1.0f;