[SkSVGDevice] Full font family support

src/svg/SkSVGDevice.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkSVGDevice.h"
 
 #include "SkBitmap.h"
+#include "SkChecksum.h"
 #include "SkDraw.h"
 #include "SkPaint.h"
 #include "SkParsePath.h"
 #include "SkPathOps.h"
 #include "SkShader.h"
 #include "SkStream.h"
+#include "SkTHash.h"
 #include "SkTypeface.h"
 #include "SkUtils.h"
 #include "SkXMLWriter.h"
 
 namespace {
 
 static SkString svg_color(SkColor color) {
     return SkStringPrintf("rgb(%u,%u,%u)",
                           SkColorGetR(color),
                           SkColorGetG(color),
@@ skipping 130 matching lines @@
             append_escaped_unichar(c32[i], &svgText);
         }
     } break;
     default:
         SkFAIL("unknown text encoding");
     }
 
     return svgText;
 }
 
+uint32_t hash_family_string(const SkString& family) {
+    // This is a lame hash function, but we don't really expect to see more than 1-2

[mtklein, 2015/02/13 15:01:20]

At least, it is not without precedent:

http://www.i-programmer.info/news/98-languages/6758-the-reason-for-the-weird-...

+    // family names under normal circumstances.
+    return SkChecksum::Mix(SkToU32(family.size()));
+}
+
 struct Resources {
     Resources(const SkPaint& paint)
         : fPaintServer(svg_color(paint.getColor())) {}
 
     SkString fPaintServer;
     SkString fClip;
 };
 
 }
 
@@ skipping 274 matching lines @@
     this->addAttribute("font-size", paint.getTextSize());
 
     SkTypeface::Style style = paint.getTypeface()->style();
     if (style & SkTypeface::kItalic) {
         this->addAttribute("font-style", "italic");
     }
     if (style & SkTypeface::kBold) {
         this->addAttribute("font-weight", "bold");
     }
 
-    SkAutoTUnref<const SkTypeface> tface(paint.getTypeface() ?
-        SkRef(paint.getTypeface()) : SkTypeface::RefDefault(style));
-    SkString familyName;
-    tface->getFamilyName(&familyName);
-    if (!familyName.isEmpty()) {
-        this->addAttribute("font-family", familyName);
-    }
-
     if (const char* textAlign = svg_text_align(paint.getTextAlign())) {
         this->addAttribute("text-anchor", textAlign);
     }
+
+    SkString familyName;
+    SkTHashSet<SkString, hash_family_string> familySet;
+    SkAutoTUnref<const SkTypeface> tface(paint.getTypeface() ?
+        SkRef(paint.getTypeface()) : SkTypeface::RefDefault(style));
+    SkAutoTUnref<SkTypeface::LocalizedStrings> familyNameIter(tface->createFamilyNameIterator());
+    SkTypeface::LocalizedString familyString;
+    while (familyNameIter->next(&familyString)) {
+        if (familySet.contains(familyString.fString)) {
+            continue;
+        }
+        familySet.add(familyString.fString);

[mtklein, 2015/02/13 15:01:20]

Well, now I want SkTHashSet's add to return a bool....

[f(malita), 2015/02/13 15:24:09]

Ack.

Yeah, that would let us avoid a double hash lookup - but it's a pattern that
will hit the current temp-copy-on-repeated-add much harder.

+        familyName.appendf((familyName.isEmpty() ? "%s" : ", %s"), familyString.fString.c_str());
+    }
+
+    if (!familyName.isEmpty()) {
+        this->addAttribute("font-family", familyName);
+    }
 }
 
 SkBaseDevice* SkSVGDevice::Create(const SkISize& size, SkXMLWriter* writer) {
     if (!writer) {
         return NULL;
     }
 
     return SkNEW_ARGS(SkSVGDevice, (size, writer));
 }
 
@@ skipping 160 matching lines @@
                                const SkPaint& paint) {
     // todo
     SkDebugf("unsupported operation: drawVertices()\n");
 }
 
 void SkSVGDevice::drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
                              const SkPaint&) {
     // todo
     SkDebugf("unsupported operation: drawDevice()\n");
 }