[pango/pango1-dwrite] pangowin32: Check for monospace using DirectWrite

[Chun-wei Fan <fanchunwei src gnome org>]

commit 82896c6ab7d3917835c866b602a305cfb47a59af
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Tue Jul 12 17:38:30 2022 +0800

    pangowin32: Check for monospace using DirectWrite
    
    ...if it is available.  It makes things much easier than GDI on this regard.

 pango/pangowin32-dwrite-fontmap.cpp | 21 ++++++++++++++++++++-
 pango/pangowin32-fontmap.c          |  6 ++++++
 pango/pangowin32-private.h          |  3 +++
 3 files changed, 29 insertions(+), 1 deletion(-)
---
diff --git a/pango/pangowin32-dwrite-fontmap.cpp b/pango/pangowin32-dwrite-fontmap.cpp
index b71870782..4e482d7d4 100644
--- a/pango/pangowin32-dwrite-fontmap.cpp
+++ b/pango/pangowin32-dwrite-fontmap.cpp
@@ -27,7 +27,7 @@
 #ifdef HAVE_DIRECTWRITE
 
 #include <initguid.h>
-#include <dwrite.h>
+#include <dwrite_1.h>
 
 #ifdef STRICT
 #undef STRICT
@@ -36,8 +36,10 @@
 
 #ifdef _MSC_VER
 # define UUID_OF_IDWriteFactory __uuidof (IDWriteFactory)
+# define UUID_OF_IDWriteFont1 __uuidof (IDWriteFont1)
 #else
 # define UUID_OF_IDWriteFactory IID_IDWriteFactory
+# define UUID_OF_IDWriteFont1 IID_IDWriteFont1
 #endif
 
 struct _PangoWin32DWriteItems
@@ -381,6 +383,23 @@ pango_win32_font_description_from_logfontw_dwrite (LOGFONTW *logfontw)
   return desc;
 }
 
+gboolean
+pango_win32_dwrite_font_is_monospace (gpointer dwrite_font)
+{
+  IDWriteFont *font = static_cast<IDWriteFont *>(dwrite_font);
+  IDWriteFont1 *font1 = NULL;
+  gboolean result = FALSE;
+
+  if (SUCCEEDED (font->QueryInterface(UUID_OF_IDWriteFont1,
+                                      reinterpret_cast<void**>(&font1))))
+    {
+      result = font1->IsMonospacedFont ();
+      font1->Release ();
+    }
+
+  return result;
+}
+
 void
 pango_win32_dwrite_font_release (gpointer dwrite_font)
 {
diff --git a/pango/pangowin32-fontmap.c b/pango/pangowin32-fontmap.c
index 695b35f3e..06ee92e04 100644
--- a/pango/pangowin32-fontmap.c
+++ b/pango/pangowin32-fontmap.c
@@ -1745,8 +1745,14 @@ pango_win32_insert_font (PangoWin32FontMap *win32fontmap,
   win32face->family = win32family =
     pango_win32_get_font_family (win32fontmap,
                                  pango_font_description_get_family (win32face->description));
+
+#if HAVE_DIRECTWRITE
+  if (dwrite_font != NULL)
+    win32family->is_monospace = pango_win32_dwrite_font_is_monospace (dwrite_font);
+#else
   if ((lfp->lfPitchAndFamily & 0xF0) == FF_MODERN)
     win32family->is_monospace = TRUE;
+#endif
 
   win32family->faces = g_slist_append (win32family->faces, win32face);
 
diff --git a/pango/pangowin32-private.h b/pango/pangowin32-private.h
index 5f6410e29..36c6207e3 100644
--- a/pango/pangowin32-private.h
+++ b/pango/pangowin32-private.h
@@ -382,6 +382,9 @@ pango_win32_font_description_from_logfontw_dwrite             (LOGFONTW *logfont
 PangoFontDescription *
 pango_win32_font_description_from_dwrite_font                 (gpointer  dwrite_font);
 
+gboolean
+pango_win32_dwrite_font_is_monospace                          (gpointer  dwrite_font);
+
 void            pango_win32_dwrite_font_release               (gpointer  dwrite_font);
 
 G_END_DECLS