pangowin32: Set up IDWriteTextAnalysis2 object if available

This is so that we can check for the OpenType features in the fonts if it is
supported by the system's DirectWrite, i.e., in Windows 8.1 or later.  If it
is unavailable, we will continue to support what we support currently.

1 files changed, 40 insertions, 3 deletions

diff --git a/pango/pangowin32-dwrite-fontmap.cpp b/pango/pangowin32-dwrite-fontmap.cpp
index 7e712b57..db033d27 100644
--- a/pango/pangowin32-dwrite-fontmap.cpp
+++ b/pango/pangowin32-dwrite-fontmap.cpp
@@ -23,7 +23,7 @@
 #include "config.h"
 
 #include <initguid.h>
-#include <dwrite_1.h>
+#include <dwrite_2.h>
 
 #ifdef STRICT
 #undef STRICT
@@ -33,15 +33,19 @@
 #ifdef _MSC_VER
 # define UUID_OF_IDWriteFactory __uuidof (IDWriteFactory)
 # define UUID_OF_IDWriteFont1 __uuidof (IDWriteFont1)
+# define UUID_OF_IDWriteTextAnalyzer2 __uuidof (IDWriteTextAnalyzer2)
 #else
 # define UUID_OF_IDWriteFactory IID_IDWriteFactory
 # define UUID_OF_IDWriteFont1 IID_IDWriteFont1
+# define UUID_OF_IDWriteTextAnalyzer2 IID_IDWriteTextAnalyzer2
 #endif
 
 struct _PangoWin32DWriteItems
 {
-  IDWriteFactory    *dwrite_factory;
-  IDWriteGdiInterop *gdi_interop;
+  IDWriteFactory       *dwrite_factory;
+  IDWriteGdiInterop    *gdi_interop;
+  IDWriteTextAnalyzer  *text_analyzer;
+  IDWriteTextAnalyzer2 *text_analyzer2;
 };
 
 PangoWin32DWriteItems *
@@ -64,6 +68,33 @@ pango_win32_init_direct_write (void)
           dwrite_items->dwrite_factory->Release ();
           failed = TRUE;
         }
+
+      /*
+       * Set up the IDWriteTextAnalyzer2 interface for our DirectWrite instance, and
+       * make it ready for use if it is available.  If it's not available, we have a
+       * reduced feature set, i.e. what we support currently.
+       */
+      if (!failed)
+        {
+           IDWriteTextAnalyzer *text_analyzer;
+           IDWriteTextAnalyzer2 *text_analyzer2;
+
+           hr = dwrite_items->dwrite_factory->CreateTextAnalyzer(&text_analyzer);
+           if (SUCCEEDED (hr) && text_analyzer != NULL)
+             {
+               if (SUCCEEDED (text_analyzer->QueryInterface(UUID_OF_IDWriteTextAnalyzer2,
+                                                            reinterpret_cast<void**>(&text_analyzer2))))
+                 {
+                   if (text_analyzer2 != NULL)
+                     {
+                       dwrite_items->text_analyzer = text_analyzer;
+                       dwrite_items->text_analyzer2 = text_analyzer2;
+                     }
+                 }
+               else
+                 text_analyzer->Release ();
+             }
+        }
     }
   else
     {
@@ -81,6 +112,12 @@ pango_win32_init_direct_write (void)
 void
 pango_win32_dwrite_items_destroy (PangoWin32DWriteItems *dwrite_items)
 {
+  if (dwrite_items->text_analyzer2 != NULL)
+    {
+      dwrite_items->text_analyzer2->Release ();
+      dwrite_items->text_analyzer->Release ();
+    }
+
   dwrite_items->gdi_interop->Release ();
   dwrite_items->dwrite_factory->Release ();