Revert "Revert "SkAdvancedTypefaceMetrics: factor out GlyphToUnicode""

This reverts commit 97c1108607584b6050a6880d6ce22846e4913a92.

Change-Id: Ic3c6addc64ced39766bbee3e10b4d88faf61ba2f
Reviewed-on: https://skia-review.googlesource.com/127021
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>

6 files changed, 45 insertions, 28 deletions

diff --git a/src/pdf/SkPDFCanon.h b/src/pdf/SkPDFCanon.h
index 8d0e8f8fed..8e97db05f5 100644
--- a/src/pdf/SkPDFCanon.h
+++ b/src/pdf/SkPDFCanon.h
@@ -42,6 +42,7 @@ public:
 
     SkTHashMap<uint32_t, std::unique_ptr<SkAdvancedTypefaceMetrics>> fTypefaceMetrics;
     SkTHashMap<uint32_t, std::vector<SkString>> fType1GlyphNames;
+    SkTHashMap<uint32_t, std::vector<SkUnichar>> fToUnicodeMap;
     SkTHashMap<uint32_t, sk_sp<SkPDFDict>> fFontDescriptors;
     SkTHashMap<uint64_t, sk_sp<SkPDFFont>> fFontMap;
 
diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index 6e36fb3d82..c18219ab0d 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -1052,8 +1052,8 @@ private:
 };
 }  // namespace
 
-static SkUnichar map_glyph(const SkTDArray<SkUnichar>& glyphToUnicode, SkGlyphID glyph) {
-    return SkToInt(glyph) < glyphToUnicode.count() ? glyphToUnicode[SkToInt(glyph)] : -1;
+static SkUnichar map_glyph(const std::vector<SkUnichar>& glyphToUnicode, SkGlyphID glyph) {
+    return glyph < glyphToUnicode.size() ? glyphToUnicode[SkToInt(glyph)] : -1;
 }
 
 static void update_font(SkWStream* wStream, int fontIndex, SkScalar textSize) {
@@ -1200,6 +1200,9 @@ void SkPDFDevice::internalDrawText(
     if (!metrics) {
         return;
     }
+    const std::vector<SkUnichar>& glyphToUnicode = SkPDFFont::GetUnicodeMap(
+        typeface, fDocument->canon());
+
     SkClusterator clusterator(sourceText, sourceByteCount, paint,
                               clusters, textByteLength, utf8Text);
     const SkGlyphID* glyphs = clusterator.glyphs();
@@ -1244,7 +1247,6 @@ void SkPDFDevice::internalDrawText(
             return;
         }
         SkDynamicMemoryWStream* out = content.stream();
-        const SkTDArray<SkUnichar>& glyphToUnicode = metrics->fGlyphToUnicode;
 
         out->writeText("BT\n");
         SK_AT_SCOPE_EXIT(out->writeText("ET\n"));
diff --git a/src/pdf/SkPDFFont.cpp b/src/pdf/SkPDFFont.cpp
index 9ba411495a..3b89f62cbe 100644
--- a/src/pdf/SkPDFFont.cpp
+++ b/src/pdf/SkPDFFont.cpp
@@ -186,6 +186,19 @@ const SkAdvancedTypefaceMetrics* SkPDFFont::GetMetrics(SkTypeface* typeface,
     return canon->fTypefaceMetrics.set(id, std::move(metrics))->get();
 }
 
+const std::vector<SkUnichar>& SkPDFFont::GetUnicodeMap(const SkTypeface* typeface,
+                                                       SkPDFCanon* canon) {
+    SkASSERT(typeface);
+    SkASSERT(canon);
+    SkFontID id = typeface->uniqueID();
+    if (std::vector<SkUnichar>* ptr = canon->fToUnicodeMap.find(id)) {
+        return *ptr;
+    }
+    std::vector<SkUnichar> buffer(typeface->countGlyphs());
+    typeface->getGlyphToUnicodeMap(buffer.data());
+    return *canon->fToUnicodeMap.set(id, std::move(buffer));
+}
+
 SkAdvancedTypefaceMetrics::FontType SkPDFFont::FontType(const SkAdvancedTypefaceMetrics& metrics) {
     if (SkToBool(metrics.fFlags & SkAdvancedTypefaceMetrics::kMultiMaster_FontFlag) ||
         SkToBool(metrics.fFlags & SkAdvancedTypefaceMetrics::kNotEmbeddable_FontFlag)) {
@@ -477,14 +490,15 @@ void SkPDFType0Font::getFontSubset(SkPDFCanon* canon) {
     descendantFonts->appendObjRef(std::move(newCIDFont));
     this->insertObject("DescendantFonts", std::move(descendantFonts));
 
-    if (metrics.fGlyphToUnicode.count() > 0) {
-        this->insertObjRef("ToUnicode",
-                           SkPDFMakeToUnicodeCmap(metrics.fGlyphToUnicode,
-                                                  &this->glyphUsage(),
-                                                  multiByteGlyphs(),
-                                                  firstGlyphID(),
-                                                  lastGlyphID()));
-    }
+    const std::vector<SkUnichar>& glyphToUnicode =
+        SkPDFFont::GetUnicodeMap(this->typeface(), canon);
+    SkASSERT(SkToSizeT(this->typeface()->countGlyphs()) == glyphToUnicode.size());
+    this->insertObjRef("ToUnicode",
+                       SkPDFMakeToUnicodeCmap(glyphToUnicode.data(),
+                                              &this->glyphUsage(),
+                                              this->multiByteGlyphs(),
+                                              this->firstGlyphID(),
+                                              this->lastGlyphID()));
     SkDEBUGCODE(fPopulated = true);
     return;
 }
@@ -722,14 +736,15 @@ static void add_type3_font_info(SkPDFCanon* canon,
     fontBBox->appendInt(bbox.top());
     font->insertObject("FontBBox", std::move(fontBBox));
     font->insertName("CIDToGIDMap", "Identity");
-    if (metrics && metrics->fGlyphToUnicode.count() > 0) {
-        font->insertObjRef("ToUnicode",
-                           SkPDFMakeToUnicodeCmap(metrics->fGlyphToUnicode,
-                                                  &subset,
-                                                  false,
-                                                  firstGlyphID,
-                                                  lastGlyphID));
-    }
+
+    const std::vector<SkUnichar>& glyphToUnicode = SkPDFFont::GetUnicodeMap(typeface, canon);
+    SkASSERT(glyphToUnicode.size() == SkToSizeT(typeface->countGlyphs()));
+    font->insertObjRef("ToUnicode",
+                       SkPDFMakeToUnicodeCmap(glyphToUnicode.data(),
+                                              &subset,
+                                              false,
+                                              firstGlyphID,
+                                              lastGlyphID));
     auto descriptor = sk_make_sp<SkPDFDict>("FontDescriptor");
     int32_t fontDescriptorFlags = kPdfSymbolic;
     if (metrics) {
diff --git a/src/pdf/SkPDFFont.h b/src/pdf/SkPDFFont.h
index 9dc4655501..1441eedad9 100644
--- a/src/pdf/SkPDFFont.h
+++ b/src/pdf/SkPDFFont.h
@@ -95,6 +95,9 @@ public:
     static const SkAdvancedTypefaceMetrics* GetMetrics(SkTypeface* typeface,
                                                        SkPDFCanon* canon);
 
+    static const std::vector<SkUnichar>& GetUnicodeMap(const SkTypeface* typeface,
+                                                       SkPDFCanon* canon);
+
     /** Subset the font based on current usage.
      *  Must be called before emitObject().
      */
diff --git a/src/pdf/SkPDFMakeToUnicodeCmap.cpp b/src/pdf/SkPDFMakeToUnicodeCmap.cpp
index afe773207d..c93aa6f2c5 100644
--- a/src/pdf/SkPDFMakeToUnicodeCmap.cpp
+++ b/src/pdf/SkPDFMakeToUnicodeCmap.cpp
@@ -147,15 +147,12 @@ static void append_bfrange_section(const SkTDArray<BFRange>& bfrange,
 // For the worst case (having 65536 continuous unicode and we use every other
 // one of them), the possible savings by aggressive optimization is 416KB
 // pre-compressed and does not provide enough motivation for implementation.
-void SkPDFAppendCmapSections(const SkTDArray<SkUnichar>& glyphToUnicode,
+void SkPDFAppendCmapSections(const SkUnichar* glyphToUnicode,
                              const SkBitSet* subset,
                              SkDynamicMemoryWStream* cmap,
                              bool multiByteGlyphs,
                              SkGlyphID firstGlyphID,
                              SkGlyphID lastGlyphID) {
-    if (glyphToUnicode.isEmpty()) {
-        return;
-    }
     int glyphOffset = 0;
     if (!multiByteGlyphs) {
         glyphOffset = firstGlyphID - 1;
@@ -166,8 +163,7 @@ void SkPDFAppendCmapSections(const SkTDArray<SkUnichar>& glyphToUnicode,
 
     BFRange currentRangeEntry = {0, 0, 0};
     bool rangeEmpty = true;
-    const int limit =
-            SkMin32(lastGlyphID + 1, glyphToUnicode.count()) - glyphOffset;
+    const int limit = (int)lastGlyphID + 1 - glyphOffset;
 
     for (int i = firstGlyphID - glyphOffset; i < limit + 1; ++i) {
         bool inSubset = i < limit &&
@@ -210,7 +206,7 @@ void SkPDFAppendCmapSections(const SkTDArray<SkUnichar>& glyphToUnicode,
 }
 
 sk_sp<SkPDFStream> SkPDFMakeToUnicodeCmap(
-        const SkTDArray<SkUnichar>& glyphToUnicode,
+        const SkUnichar* glyphToUnicode,
         const SkBitSet* subset,
         bool multiByteGlyphs,
         SkGlyphID firstGlyphID,
diff --git a/src/pdf/SkPDFMakeToUnicodeCmap.h b/src/pdf/SkPDFMakeToUnicodeCmap.h
index 0c4d1c37dd..656af913d0 100644
--- a/src/pdf/SkPDFMakeToUnicodeCmap.h
+++ b/src/pdf/SkPDFMakeToUnicodeCmap.h
@@ -12,14 +12,14 @@
 #include "SkStream.h"
 
 sk_sp<SkPDFStream> SkPDFMakeToUnicodeCmap(
-        const SkTDArray<SkUnichar>& glyphToUnicode,
+        const SkUnichar* glyphToUnicode,
         const SkBitSet* subset,
         bool multiByteGlyphs,
         SkGlyphID firstGlyphID,
         SkGlyphID lastGlyphID);
 
 // Exposed for unit testing.
-void SkPDFAppendCmapSections(const SkTDArray<SkUnichar>& glyphToUnicode,
+void SkPDFAppendCmapSections(const SkUnichar* glyphToUnicode,
                              const SkBitSet* subset,
                              SkDynamicMemoryWStream* cmap,
                              bool multiByteGlyphs,