[prev in list] [next in list] [prev in thread] [next in thread] 

List:       freetype-devel
Subject:    Re: [ft-devel] Minor FT_Set_Var_Design_Coordinates() request
From:       Matthias Clasen <matthias.clasen () gmail ! com>
Date:       2017-12-18 18:49:20
Message-ID: CAFwd_vB_P15ns6c2KWiimP_hu_wtf5Jygf8tp=pKKDaLJXFW4w () mail ! gmail ! com
[Download RAW message or body]

[Attachment #2 (multipart/alternative)]


On Mon, Dec 18, 2017 at 1:39 PM, Behdad Esfahbod <behdad@behdad.org> wrote:

> Hi Werner,
>
> Is there any chance you can modify FT_Set_Var_Design_Coordinates() to
> detect when the set face coordinates are not changed and shortcircuit out
> early?  Currently, if one calls that function too often (say, for every
> glyph load, which is how we want to call it in cairo), it causes font
> metrics and autohinter reinitialization even if the coordinates didn't
> change.  Can you please fix that?  Matthias and I are hacking together this
> week, trying to finish font variations support in the Pango stack.
>
> Thanks,
>
> --
> behdad
> http://behdad.org/
>

Here is a quick hack to demonstrate the idea

[Attachment #5 (text/html)]

<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Dec \
18, 2017 at 1:39 PM, Behdad Esfahbod <span dir="ltr">&lt;<a \
href="mailto:behdad@behdad.org" target="_blank">behdad@behdad.org</a>&gt;</span> \
wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px \
#ccc solid;padding-left:1ex"><div dir="ltr"><div><div>Hi Werner,<br><br></div>Is \
there any chance you can modify FT_Set_Var_Design_Coordinates(<wbr>) to detect when \
the set face coordinates are not changed and shortcircuit out early?   Currently, if \
one calls that function too often (say, for every glyph load, which is how we want to \
call it in cairo), it causes font metrics and autohinter reinitialization even if the \
coordinates didn&#39;t change.   Can you please fix that?   Matthias and I are \
hacking together this week, trying to finish font variations support in the Pango \
stack.<br><br></div>Thanks,<span class="HOEnZb"><font color="#888888"><br \
clear="all"><div><div><div><br>-- <br><div \
class="m_-6647617913516074517gmail_signature">behdad<br><a href="http://behdad.org/" \
target="_blank">http://behdad.org/</a></div> </div></div></div></font></span></div>
</blockquote></div></div><div class="gmail_extra"><br></div><div \
class="gmail_extra">Here is a quick hack to demonstrate the idea<br></div></div>

--001a11406c0af2d0a50560a1cec0--


["font-variations-shortcut.patch" (text/x-patch)]

diff --git a/src/base/ftmm.c b/src/base/ftmm.c
index e0131ece3..1f2be46f8 100644
--- a/src/base/ftmm.c
+++ b/src/base/ftmm.c
@@ -24,6 +24,7 @@
 #include FT_SERVICE_MULTIPLE_MASTERS_H
 #include FT_SERVICE_METRICS_VARIATIONS_H
 
+#include <alloca.h>
 
   /*************************************************************************/
   /*                                                                       */
@@ -201,6 +202,25 @@
     if ( !error )
     {
       error = FT_ERR( Invalid_Argument );
+      if ( service_mm->get_var_design )
+        {
+          FT_Fixed *my_coords;
+          FT_UInt i;
+
+          my_coords = alloca (sizeof(FT_Fixed) * num_coords);
+
+          error = service_mm->get_var_design( face, num_coords, my_coords );
+          if (error)
+            return error;
+
+          for (i = 0; i < num_coords; i++)
+            {
+              if (coords[i] != my_coords[i])
+                break;
+            }
+          if (i == num_coords)
+            return 0;
+        }
       if ( service_mm->set_var_design )
         error = service_mm->set_var_design( face, num_coords, coords );
     }


_______________________________________________
Freetype-devel mailing list
Freetype-devel@nongnu.org
https://lists.nongnu.org/mailman/listinfo/freetype-devel


[prev in list] [next in list] [prev in thread] [next in thread]