[Freetype] Add basic implementation of FontCustomPlatformData::suppor…

…tsTechnology

https://bugs.webkit.org/show_bug.cgi?id=256310

Reviewed by Michael Catanzaro.

Instead of unconditionally returning true this explicitly handles the technologies.

* Source/WebCore/platform/graphics/freetype/FontCustomPlatformDataFreeType.cpp:
(WebCore::FontCustomPlatformData::supportsTechnology):
* Source/cmake/FindHarfBuzz.cmake:

Canonical link: https://commits.webkit.org/273584@main

Source/WebCore/platform/graphics/freetype/FontCustomPlatformDataFreeType.cpp

@@ -38,6 +38,13 @@
 #include FT_MODULE_H
 #include <mutex>
 
+#ifdef HAVE_HB_FEATURES_H
+// Workaround https://github.com/harfbuzz/harfbuzz/commit/30c5402e3d0cc156fd5f04560864a88723173cf2
+#define HB_NO_SINGLE_HEADER_ERROR
+#include <hb-features.h>
+#undef HB_NO_SINGLE_HEADER_ERROR
+#endif
+
 namespace WebCore {
 
 static cairo_user_data_key_t freeTypeFaceKey;
@@ -166,10 +173,36 @@ bool FontCustomPlatformData::supportsFormat(const String& format)
         || equalLettersIgnoringASCIICase(format, "svg"_s);
 }
 
-bool FontCustomPlatformData::supportsTechnology(const FontTechnology&)
+bool FontCustomPlatformData::supportsTechnology(const FontTechnology& technology)
 {
-    // FIXME: define supported technologies for this platform (webkit.org/b/256310).
-    return true;
+#if USE(HARFBUZZ)
+    // https://harfbuzz.github.io/what-does-harfbuzz-do.html
+    // Many of these features *could* be disabled but hb doesn't easily expose
+    // this and it is unlikely.
+    switch (technology) {
+    case FontTechnology::ColorCbdt:
+    case FontTechnology::ColorColrv0:
+    case FontTechnology::ColorColrv1:
+    case FontTechnology::ColorSbix:
+    case FontTechnology::ColorSvg:
+    case FontTechnology::FeaturesAat:
+    case FontTechnology::FeaturesOpentype:
+    case FontTechnology::Incremental:
+    case FontTechnology::Palettes:
+    case FontTechnology::Variations:
+        return true;
+    case FontTechnology::Invalid:
+        return false;
+    case FontTechnology::FeaturesGraphite:
+#ifdef HB_HAS_GRAPHITE
+        return true;
+#else
+        return false;
+#endif
+    }
+#endif
+
+    return false;
 }
 
 }

Source/cmake/FindHarfBuzz.cmake

@@ -134,6 +134,12 @@ if ("ICU" IN_LIST HarfBuzz_FIND_COMPONENTS)
     endif ()
 endif ()
 
+# Workaround https://github.com/harfbuzz/harfbuzz/pull/4562
+if (HarfBuzz_INCLUDE_DIR AND EXISTS "${HarfBuzz_INCLUDE_DIR}/hb-features.h")
+    list(APPEND HarfBuzz_COMPILE_OPTIONS "-DHAVE_HB_FEATURES_H")
+    message(STATUS "Found hb-features.h")
+endif ()
+
 if (NOT HarfBuzz_FIND_QUIETLY)
     if (HarfBuzz_LIBS_FOUND)
         message(STATUS "Found the following HarfBuzz libraries:")