Implement support for rendering color emoji on Windows

tools/sk_tool_utils.cpp

Index: tools/sk_tool_utils.cpp
diff --git a/tools/sk_tool_utils.cpp b/tools/sk_tool_utils.cpp
index 7343ce4744e661bd5a08600fb58df0d202c6d253..fd53e98ea51020b459ca9d202f9dc74cc5cadf5f 100644
--- a/tools/sk_tool_utils.cpp
+++ b/tools/sk_tool_utils.cpp
@@ -12,6 +12,8 @@
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkCommonFlags.h"
+#include "SkFontMgr.h"
+#include "SkFontStyle.h"
 #include "SkPoint3.h"
 #include "SkShader.h"
 #include "SkTestScalerContext.h"
@@ -72,6 +74,9 @@ const char* platform_os_emoji() {
     if (!strncmp(osName, "Mac", 3)) {
         return "SBIX";
     }
+    if (!strncmp(osName, "Win", 3)) {
+        return "COLR";
+    }
     return "";
 }
 
@@ -82,6 +87,23 @@ sk_sp<SkTypeface> emoji_typeface() {
     if (!strcmp(sk_tool_utils::platform_os_emoji(), "SBIX")) {
         return SkTypeface::MakeFromName("Apple Color Emoji", SkTypeface::kNormal);
     }
+    if (!strcmp(sk_tool_utils::platform_os_emoji(), "COLR")) {
+        sk_sp<SkFontMgr> fm(SkFontMgr::RefDefault());
+        const char *colorEmojiFontName = "Segoe UI Emoji";
+        sk_sp<SkTypeface> typeface(fm->matchFamilyStyle(colorEmojiFontName, SkFontStyle()));
+        if (typeface) {
+            return typeface;
+        }
+        const char *bcp47 = "en-us";

[bungeman-skia, 2016/05/27 12:51:39]

en-US

Windows may or may not care. Also, I think you can just pass in nullptr and 0,
I'm not sure we actually care about the language here? In fact, technically,
there is a particular language tag for emoji, but I don't think Windows
understands it until Windows 10 with some update.

[Ilya Kulshin, 2016/05/28 02:59:46]

Switched to nullptr/0.

+        sk_sp<SkTypeface> fallback(fm->matchFamilyStyleCharacter(

[bungeman-skia, 2016/05/27 12:51:39]

Note that matchFamilyStyleCharacter was never implemented in the GDI font
manager and we need to keep that working for other reasons. So on GDI this call
will always return nullptr, so it's still a good idea to still have the
MakeFromName below.

[Ilya Kulshin, 2016/05/28 02:59:46]

Acknowledged.

+            colorEmojiFontName, SkFontStyle(), &bcp47, 1 /* bcp47Count */, 0x1f4b0 /* character: 💰 */));

[bungeman-skia, 2016/05/27 12:51:39]

nit: this line is a bit long (Skia uses 100 characters).

[Ilya Kulshin, 2016/05/28 02:59:46]

Done.

+        if (fallback) {
+            return fallback;
+        }
+        // If we don't have Segoe UI Emoji and can't find a fallback, try Segoe UI Symbol.
+        // Windows 7 does not have Segoe UI Emoji; Segoe UI Symbol has the (non - color) emoji.
+        return SkTypeface::MakeFromName("Segoe UI Symbol", SkTypeface::kNormal);
+    }
     return nullptr;
 }
 
@@ -89,7 +111,9 @@ const char* emoji_sample_text() {
     if (!strcmp(sk_tool_utils::platform_os_emoji(), "CBDT")) {
         return "Hamburgefons";
     }
-    if (!strcmp(sk_tool_utils::platform_os_emoji(), "SBIX")) {
+    if (!strcmp(sk_tool_utils::platform_os_emoji(), "SBIX") ||
+        !strcmp(sk_tool_utils::platform_os_emoji(), "COLR"))
+    {
         return "\xF0\x9F\x92\xB0" "\xF0\x9F\x8F\xA1" "\xF0\x9F\x8E\x85"  // 💰🏡🎅
                "\xF0\x9F\x8D\xAA" "\xF0\x9F\x8D\x95" "\xF0\x9F\x9A\x80"  // 🍪🍕🚀
                "\xF0\x9F\x9A\xBB" "\xF0\x9F\x92\xA9" "\xF0\x9F\x93\xB7" // 🚻💩📷