Some usability ideas around SkTHash.

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 "SkBase64.h"
@@ skipping 85 matching lines @@
         tstr.printf("matrix(%g %g %g %g %g %g)",
                     t.getScaleX(),     t.getSkewY(),
                     t.getSkewX(),      t.getScaleY(),
                     t.getTranslateX(), t.getTranslateY());
         break;
     }
 
     return tstr;
 }
 
-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
-    // 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;
 };
 
 class SVGTextBuilder : SkNoncopyable {
 public:
@@ skipping 409 matching lines @@
 }
 
 void SkSVGDevice::AutoElement::addTextAttributes(const SkPaint& paint) {
     this->addAttribute("font-size", paint.getTextSize());
 
     if (const char* textAlign = svg_text_align(paint.getTextAlign())) {
         this->addAttribute("text-anchor", textAlign);
     }
 
     SkString familyName;
-    SkTHashSet<SkString, hash_family_string> familySet;
+    SkTHashSet<SkString> familySet;
     SkAutoTUnref<const SkTypeface> tface(paint.getTypeface() ?
         SkRef(paint.getTypeface()) : SkTypeface::RefDefault());
 
     SkASSERT(tface);
     SkTypeface::Style style = tface->style();
     if (style & SkTypeface::kItalic) {
         this->addAttribute("font-style", "italic");
     }
     if (style & SkTypeface::kBold) {
         this->addAttribute("font-weight", "bold");
@@ skipping 234 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");
 }