Dwrite: implement is_synthetic()

3 files changed, 171 insertions, 7 deletions

diff --git a/src/win32/cairo-dwrite-font.cpp b/src/win32/cairo-dwrite-font.cpp
index 4c9270a59..d4f21c561 100644
--- a/src/win32/cairo-dwrite-font.cpp
+++ b/src/win32/cairo-dwrite-font.cpp
@@ -245,8 +245,12 @@ _cairo_dwrite_load_truetype_table(void		       *scaled_font,
 				  unsigned long        *length);
 
 unsigned long
-_cairo_dwrite_ucs4_to_index(void			     *scaled_font,
-			    uint32_t			ucs4);
+_cairo_dwrite_ucs4_to_index(void		       *scaled_font,
+			    uint32_t                    ucs4);
+
+cairo_int_status_t
+static _cairo_dwrite_is_synthetic(void                *scaled_font,
+			   cairo_bool_t               *is_synthetic);
 
 static cairo_bool_t
 _cairo_dwrite_has_color_glyphs(void *scaled_font);
@@ -259,7 +263,7 @@ const cairo_scaled_font_backend_t _cairo_dwrite_scaled_font_backend = {
     _cairo_dwrite_ucs4_to_index,
     _cairo_dwrite_load_truetype_table,
     NULL, /* index_to_ucs4 */
-    NULL, /* is_synthetic */
+    _cairo_dwrite_is_synthetic,
     NULL, /* index_to_glyph_name */
     NULL, /* load_type1_data */
     _cairo_dwrite_has_color_glyphs
@@ -1215,6 +1219,79 @@ _cairo_dwrite_load_truetype_table(void                 *scaled_font,
     return (cairo_int_status_t)CAIRO_STATUS_SUCCESS;
 }
 
+static cairo_int_status_t
+_cairo_dwrite_is_synthetic(void                      *scaled_font,
+			   cairo_bool_t              *is_synthetic)
+{
+    cairo_dwrite_scaled_font_t *dwritesf = static_cast<cairo_dwrite_scaled_font_t*>(scaled_font);
+    cairo_dwrite_font_face_t *face = reinterpret_cast<cairo_dwrite_font_face_t*>(dwritesf->base.font_face);
+    HRESULT hr;
+    cairo_int_status_t status;
+
+    if (face->dwriteface->GetSimulations() != DWRITE_FONT_SIMULATIONS_NONE) {
+	*is_synthetic = FALSE;
+	return CAIRO_INT_STATUS_SUCCESS;
+    }
+
+    IDWriteFontFace5 *fontFace5 = NULL;
+    if (!SUCCEEDED(face->dwriteface->QueryInterface(&fontFace5))) {
+	/* If IDWriteFontFace5 is not available, assume this version of
+	 * DirectWrite does not support variations.
+	 */
+	*is_synthetic = FALSE;
+	return CAIRO_INT_STATUS_SUCCESS;
+    }
+
+    if (!fontFace5->HasVariations()) {
+	*is_synthetic = FALSE;
+	return CAIRO_INT_STATUS_SUCCESS;
+    }
+
+    IDWriteFontResource *fontResource = NULL;
+    hr = fontFace5->GetFontResource(&fontResource);
+    if (!SUCCEEDED(hr))
+	return _cairo_dwrite_error (hr, "GetFontResource failed");
+
+    UINT32 axis_count = fontResource->GetFontAxisCount();
+    DWRITE_FONT_AXIS_VALUE *axis_defaults = new DWRITE_FONT_AXIS_VALUE[axis_count];
+    DWRITE_FONT_AXIS_VALUE *axis_values = new DWRITE_FONT_AXIS_VALUE[axis_count];
+
+    hr = fontResource->GetDefaultFontAxisValues(axis_defaults, axis_count);
+    if (!SUCCEEDED(hr)) {
+	status = _cairo_dwrite_error (hr, "GetDefaultFontAxisValues failed");
+	goto cleanup;
+    }
+
+    hr = fontFace5->GetFontAxisValues(axis_values, axis_count);
+    if (!SUCCEEDED(hr)) {
+	status = _cairo_dwrite_error (hr, "GetFontAxisValues failed");
+	goto cleanup;
+    }
+
+    /* The DirectWrite documentation does not state if the tags of the returned
+     * defaults and values arrays are in the same order. So assume they are not.
+     */
+    *is_synthetic = FALSE;
+    status = CAIRO_INT_STATUS_SUCCESS;
+    for (UINT32 i = 0; i< axis_count; i++) {
+	for (UINT32 j = 0; j < axis_count; j++) {
+	    if (axis_values[i].axisTag == axis_defaults[j].axisTag) {
+		if (axis_values[i].value != axis_defaults[j].value) {
+		    *is_synthetic = TRUE;
+		    goto cleanup;
+		}
+		break;
+	    }
+	}
+    }
+
+  cleanup:
+    delete[] axis_defaults;
+    delete[] axis_values;
+    
+    return status;
+}
+
 static cairo_bool_t
 _cairo_dwrite_has_color_glyphs(void *scaled_font)
 {
diff --git a/src/win32/cairo-dwrite-private.hpp b/src/win32/cairo-dwrite-private.hpp
index 07fb0e765..d9b8ec653 100644
--- a/src/win32/cairo-dwrite-private.hpp
+++ b/src/win32/cairo-dwrite-private.hpp
@@ -38,8 +38,8 @@
 #include <dwrite.h>
 #include <d2d1.h>
 
-/* If either of the dwrite_2.h or d2d1_3.h headers required for color fonts
- * is not available, include our own version containing just the functions we need.
+/* If either of the dwrite_3.h or d2d1_3.h headers required for color fonts
+ * are not available, include our own version containing just the functions we need.
  */
 
 #if HAVE_DWRITE_3_H
diff --git a/src/win32/dw-extra.h b/src/win32/dw-extra.h
index f6e37e609..4203f3427 100644
--- a/src/win32/dw-extra.h
+++ b/src/win32/dw-extra.h
@@ -2,8 +2,15 @@
 
 /* Mingw-w64 dwrite_3.h is broken
  *
- * We only need the definitions of one function and its dependencies.
- *   IDWriteFactory4::TranslateColorGlyphRun
+ * We only need the definitions of the following functions and their dependencies.
+ *   IDWriteFactory4::TranslateColorGlyphRun()
+ *   IDWriteFontResource::GetDefaultFontAxisValues()
+ *   IDWriteFontResource::GetFontAxisCount()
+ *   IDWriteFontResource::HasVariations()
+ *   IDWriteFontFace5::GetFontAxisValueCount()
+ *   IDWriteFontFace5::GetFontAxisValues()
+ *   IDWriteFontFace5::HasVariations()
+ *   IDWriteFontFace5::GetFontResource()
  *
  * But we need to include all the prior functions in the same struct,
  * and parent structs, so that the functions are in the correct position
@@ -74,5 +81,85 @@ IDWriteFactory4 : public IDWriteFactory3
 };
 __CRT_UUID_DECL(IDWriteFactory4, 0x4b0b5bd3, 0x0797, 0x4549, 0x8a,0xc5, 0xfe,0x91,0x5c,0xc5,0x38,0x56)
 
+typedef enum DWRITE_FONT_AXIS_TAG {
+    DWRITE_FONT_AXIS_TAG_WEIGHT = 0x74686777,
+    DWRITE_FONT_AXIS_TAG_WIDTH = 0x68746477,
+    DWRITE_FONT_AXIS_TAG_SLANT = 0x746e6c73,
+    DWRITE_FONT_AXIS_TAG_OPTICAL_SIZE = 0x7a73706f,
+    DWRITE_FONT_AXIS_TAG_ITALIC = 0x6c617469
+} DWRITE_FONT_AXIS_TAG;
+
+typedef struct DWRITE_FONT_AXIS_VALUE {
+    DWRITE_FONT_AXIS_TAG axisTag;
+    FLOAT value;
+} DWRITE_FONT_AXIS_VALUE;
+
+DEFINE_GUID(IID_IDWriteFontResource, 0x1f803a76, 0x6871, 0x48e8, 0x98,0x7f, 0xb9,0x75,0x55,0x1c,0x50,0xf2);
+MIDL_INTERFACE("1f803a76-6871-48e8-987f-b975551c50f2")
+IDWriteFontResource : public IUnknown
+{
+  virtual void STDMETHODCALLTYPE GetFontFile() = 0;
+  virtual void STDMETHODCALLTYPE GetFontFaceIndex() = 0;
+  virtual UINT32 STDMETHODCALLTYPE GetFontAxisCount() = 0;
+  virtual HRESULT STDMETHODCALLTYPE GetDefaultFontAxisValues(
+    const DWRITE_FONT_AXIS_VALUE *values,
+    UINT32 num_values) = 0;
+  virtual void STDMETHODCALLTYPE GetFontAxisRanges() = 0;
+  virtual void STDMETHODCALLTYPE GetFontAxisAttributes() = 0;
+  virtual void STDMETHODCALLTYPE GetAxisNames() = 0;
+  virtual void STDMETHODCALLTYPE GetAxisValueNameCount() = 0;
+  virtual void STDMETHODCALLTYPE GetAxisValueNames() = 0;
+  virtual WINBOOL STDMETHODCALLTYPE HasVariations() = 0;
+  virtual void STDMETHODCALLTYPE CreateFontFace() = 0;
+  virtual void STDMETHODCALLTYPE CreateFontFaceReference() = 0;
+};
+__CRT_UUID_DECL(IDWriteFontResource, 0x1f803a76, 0x6871, 0x48e8, 0x98,0x7f, 0xb9,0x75,0x55,0x1c,0x50,0xf2)
+
+DEFINE_GUID(IID_IDWriteFontFace3, 0xd37d7598, 0x09be, 0x4222, 0xa2,0x36, 0x20,0x81,0x34,0x1c,0xc1,0xf2);
+MIDL_INTERFACE("d37d7598-09be-4222-a236-2081341cc1f2")
+IDWriteFontFace3 : public IDWriteFontFace2
+{
+  virtual void STDMETHODCALLTYPE GetFontFaceReference() = 0;
+  virtual void STDMETHODCALLTYPE GetPanose() = 0;
+  virtual void STDMETHODCALLTYPE GetWeight() = 0;
+  virtual void STDMETHODCALLTYPE GetStretch() = 0;
+  virtual void STDMETHODCALLTYPE GetStyle() = 0;
+  virtual void STDMETHODCALLTYPE GetFamilyNames() = 0;
+  virtual void STDMETHODCALLTYPE GetFaceNames() = 0;
+  virtual void STDMETHODCALLTYPE GetInformationalStrings() = 0;
+  virtual void STDMETHODCALLTYPE HasCharacter() = 0;
+  virtual void STDMETHODCALLTYPE GetRecommendedRenderingMode() = 0;
+  virtual void STDMETHODCALLTYPE IsCharacterLocal() = 0;
+  virtual void STDMETHODCALLTYPE IsGlyphLocal() = 0;
+  virtual void STDMETHODCALLTYPE AreCharactersLocal() = 0;
+  virtual void STDMETHODCALLTYPE AreGlyphsLocal() = 0;
+};
+__CRT_UUID_DECL(IDWriteFontFace3, 0xd37d7598, 0x09be, 0x4222, 0xa2,0x36, 0x20,0x81,0x34,0x1c,0xc1,0xf2)
+
+DEFINE_GUID(IID_IDWriteFontFace4, 0x27f2a904, 0x4eb8, 0x441d, 0x96,0x78, 0x05,0x63,0xf5,0x3e,0x3e,0x2f);
+MIDL_INTERFACE("27f2a904-4eb8-441d-9678-0563f53e3e2f")
+IDWriteFontFace4 : public IDWriteFontFace3
+{
+  virtual void STDMETHODCALLTYPE GetGlyphImageFormats_() = 0;
+  virtual void STDMETHODCALLTYPE GetGlyphImageFormats() = 0;
+  virtual void STDMETHODCALLTYPE GetGlyphImageData() = 0;
+  virtual void STDMETHODCALLTYPE ReleaseGlyphImageData() = 0;
+};
+__CRT_UUID_DECL(IDWriteFontFace4, 0x27f2a904, 0x4eb8, 0x441d, 0x96,0x78, 0x05,0x63,0xf5,0x3e,0x3e,0x2f)
+
+DEFINE_GUID(IID_IDWriteFontFace5, 0x98eff3a5, 0xb667, 0x479a, 0xb1,0x45, 0xe2,0xfa,0x5b,0x9f,0xdc,0x29);
+MIDL_INTERFACE("98eff3a5-b667-479a-b145-e2fa5b9fdc29")
+IDWriteFontFace5 : public IDWriteFontFace4
+{
+  virtual UINT32 STDMETHODCALLTYPE GetFontAxisValueCount() = 0;
+  virtual HRESULT STDMETHODCALLTYPE GetFontAxisValues(
+    DWRITE_FONT_AXIS_VALUE *values,
+    UINT32 value_count) = 0;
+  virtual WINBOOL STDMETHODCALLTYPE HasVariations() = 0;
+  virtual HRESULT STDMETHODCALLTYPE GetFontResource(
+    IDWriteFontResource **resource) = 0;
+  virtual void STDMETHODCALLTYPE Equals() = 0;
+};
+__CRT_UUID_DECL(IDWriteFontFace5, 0x98eff3a5, 0xb667, 0x479a, 0xb1,0x45, 0xe2,0xfa,0x5b,0x9f,0xdc,0x29)
 
 #endif /* DWRITE_EXTRA_H */