Correct advances for 'monospace' fonts in PDF.

FT_IS_FIXED_WIDTH, kCTFontMonoSpaceTrait, and TMPF_FIXED_PITCH
are style bits, they do not imply that all advances are the same.

BUG=skia:5537
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2162023002

Review-Url: https://codereview.chromium.org/2162023002

3 files changed, 80 insertions, 127 deletions

diff --git a/src/ports/SkFontHost_FreeType.cpp b/src/ports/SkFontHost_FreeType.cpp
index 2780a32d09..4a1f12babe 100644
--- a/src/ports/SkFontHost_FreeType.cpp
+++ b/src/ports/SkFontHost_FreeType.cpp
@@ -482,21 +482,17 @@ SkAdvancedTypefaceMetrics* SkTypeface_FreeType::onGetAdvancedTypefaceMetrics(
     info->fLastGlyphID = face->num_glyphs - 1;
     info->fEmSize = 1000;
 
-    bool cid = false;
     const char* fontType = FT_Get_X11_Font_Format(face);
     if (strcmp(fontType, "Type 1") == 0) {
         info->fType = SkAdvancedTypefaceMetrics::kType1_Font;
     } else if (strcmp(fontType, "CID Type 1") == 0) {
         info->fType = SkAdvancedTypefaceMetrics::kType1CID_Font;
-        cid = true;
     } else if (strcmp(fontType, "CFF") == 0) {
         info->fType = SkAdvancedTypefaceMetrics::kCFF_Font;
     } else if (strcmp(fontType, "TrueType") == 0) {
         info->fType = SkAdvancedTypefaceMetrics::kTrueType_Font;
-        cid = true;
         TT_Header* ttHeader;
-        if ((ttHeader = (TT_Header*)FT_Get_Sfnt_Table(face,
-                                                      ft_sfnt_head)) != nullptr) {
+        if ((ttHeader = (TT_Header*)FT_Get_Sfnt_Table(face, ft_sfnt_head)) != nullptr) {
             info->fEmSize = ttHeader->Units_Per_EM;
         }
     } else {
@@ -504,19 +500,19 @@ SkAdvancedTypefaceMetrics* SkTypeface_FreeType::onGetAdvancedTypefaceMetrics(
     }
 
     info->fStyle = 0;
-    if (FT_IS_FIXED_WIDTH(face))
+    if (FT_IS_FIXED_WIDTH(face)) {
         info->fStyle |= SkAdvancedTypefaceMetrics::kFixedPitch_Style;
-    if (face->style_flags & FT_STYLE_FLAG_ITALIC)
+    }
+    if (face->style_flags & FT_STYLE_FLAG_ITALIC) {
         info->fStyle |= SkAdvancedTypefaceMetrics::kItalic_Style;
+    }
 
-    PS_FontInfoRec ps_info;
-    TT_Postscript* tt_info;
-    if (FT_Get_PS_Font_Info(face, &ps_info) == 0) {
-        info->fItalicAngle = ps_info.italic_angle;
-    } else if ((tt_info =
-                (TT_Postscript*)FT_Get_Sfnt_Table(face,
-                                                  ft_sfnt_post)) != nullptr) {
-        info->fItalicAngle = SkFixedToScalar(tt_info->italicAngle);
+    PS_FontInfoRec psFontInfo;
+    TT_Postscript* postTable;
+    if (FT_Get_PS_Font_Info(face, &psFontInfo) == 0) {
+        info->fItalicAngle = psFontInfo.italic_angle;
+    } else if ((postTable = (TT_Postscript*)FT_Get_Sfnt_Table(face, ft_sfnt_post)) != nullptr) {
+        info->fItalicAngle = SkFixedToScalar(postTable->italicAngle);
     } else {
         info->fItalicAngle = 0;
     }
@@ -540,20 +536,22 @@ SkAdvancedTypefaceMetrics* SkTypeface_FreeType::onGetAdvancedTypefaceMetrics(
         }
     }
 
-    TT_PCLT* pclt_info;
-    TT_OS2* os2_table;
-    if ((pclt_info = (TT_PCLT*)FT_Get_Sfnt_Table(face, ft_sfnt_pclt)) != nullptr) {
-        info->fCapHeight = pclt_info->CapHeight;
-        uint8_t serif_style = pclt_info->SerifStyle & 0x3F;
-        if (serif_style >= 2 && serif_style <= 6)
+    TT_PCLT* pcltTable;
+    TT_OS2* os2Table;
+    if ((pcltTable = (TT_PCLT*)FT_Get_Sfnt_Table(face, ft_sfnt_pclt)) != nullptr) {
+        info->fCapHeight = pcltTable->CapHeight;
+        uint8_t serif_style = pcltTable->SerifStyle & 0x3F;
+        if (2 <= serif_style && serif_style <= 6) {
             info->fStyle |= SkAdvancedTypefaceMetrics::kSerif_Style;
-        else if (serif_style >= 9 && serif_style <= 12)
+        } else if (9 <= serif_style && serif_style <= 12) {
             info->fStyle |= SkAdvancedTypefaceMetrics::kScript_Style;
-    } else if (((os2_table = (TT_OS2*)FT_Get_Sfnt_Table(face, ft_sfnt_os2)) != nullptr) &&
+        }
+    } else if (((os2Table = (TT_OS2*)FT_Get_Sfnt_Table(face, ft_sfnt_os2)) != nullptr) &&
                // sCapHeight is available only when version 2 or later.
-               os2_table->version != 0xFFFF &&
-               os2_table->version >= 2) {
-        info->fCapHeight = os2_table->sCapHeight;
+               os2Table->version != 0xFFFF &&
+               os2Table->version >= 2)
+    {
+        info->fCapHeight = os2Table->sCapHeight;
     } else {
         // Figure out a good guess for CapHeight: average the height of M and X.
         FT_BBox m_bbox, x_bbox;
@@ -561,8 +559,7 @@ SkAdvancedTypefaceMetrics* SkTypeface_FreeType::onGetAdvancedTypefaceMetrics(
         got_m = GetLetterCBox(face, 'M', &m_bbox);
         got_x = GetLetterCBox(face, 'X', &x_bbox);
         if (got_m && got_x) {
-            info->fCapHeight = (m_bbox.yMax - m_bbox.yMin + x_bbox.yMax -
-                    x_bbox.yMin) / 2;
+            info->fCapHeight = ((m_bbox.yMax - m_bbox.yMin) + (x_bbox.yMax - x_bbox.yMin)) / 2;
         } else if (got_m && !got_x) {
             info->fCapHeight = m_bbox.yMax - m_bbox.yMin;
         } else if (!got_m && got_x) {
@@ -581,62 +578,33 @@ SkAdvancedTypefaceMetrics* SkTypeface_FreeType::onGetAdvancedTypefaceMetrics(
     }
 
     if (perGlyphInfo & kHAdvance_PerGlyphInfo) {
-        if (FT_IS_FIXED_WIDTH(face)) {
-            SkAdvancedTypefaceMetrics::WidthRange range(0);
-            int16_t advance = face->max_advance_width;
-            range.fAdvance.append(1, &advance);
-            SkAdvancedTypefaceMetrics::FinishRange(
-                    &range, 0, SkAdvancedTypefaceMetrics::WidthRange::kDefault);
-            info->fGlyphWidths.emplace_back(std::move(range));
-        } else if (!cid) {
-            SkAdvancedTypefaceMetrics::WidthRange range(0);
-            // So as to not blow out the stack, get advances in batches.
-            for (int gID = 0; gID < face->num_glyphs; gID += 128) {
-                FT_Fixed advances[128];
-                int advanceCount = 128;
-                if (gID + advanceCount > face->num_glyphs) {
-                    advanceCount = face->num_glyphs - gID;
-                }
-                FT_Get_Advances(face, gID, advanceCount, FT_LOAD_NO_SCALE, advances);
-                for (int i = 0; i < advanceCount; i++) {
-                    int16_t advance = advances[i];
-                    range.fAdvance.append(1, &advance);
+        info->setGlyphWidths(
+            face->num_glyphs,
+            glyphIDs,
+            glyphIDsCount,
+            SkAdvancedTypefaceMetrics::GetAdvance([face](int gId, int16_t* data) {
+                FT_Fixed advance = 0;
+                if (FT_Get_Advances(face, gId, 1, FT_LOAD_NO_SCALE, &advance)) {
+                    return false;
                 }
-            }
-            SkAdvancedTypefaceMetrics::FinishRange(
-                    &range, face->num_glyphs - 1,
-                    SkAdvancedTypefaceMetrics::WidthRange::kRange);
-            info->fGlyphWidths.emplace_back(std::move(range));
-        } else {
-            info->setGlyphWidths(
-                face->num_glyphs,
-                glyphIDs,
-                glyphIDsCount,
-                SkAdvancedTypefaceMetrics::GetAdvance([face](int gId, int16_t* data) {
-                    FT_Fixed advance = 0;
-                    if (FT_Get_Advances(face, gId, 1, FT_LOAD_NO_SCALE, &advance)) {
-                        return false;
-                    }
-                    SkASSERT(data);
-                    *data = advance;
-                    return true;
-                })
-            );
-        }
+                SkASSERT(data);
+                *data = advance;
+                return true;
+            })
+        );
     }
 
-    if (perGlyphInfo & kVAdvance_PerGlyphInfo &&
-            FT_HAS_VERTICAL(face)) {
+    if (perGlyphInfo & kVAdvance_PerGlyphInfo && FT_HAS_VERTICAL(face)) {
         SkASSERT(false);  // Not implemented yet.
     }
 
     if (perGlyphInfo & kGlyphNames_PerGlyphInfo &&
-            info->fType == SkAdvancedTypefaceMetrics::kType1_Font) {
+        info->fType == SkAdvancedTypefaceMetrics::kType1_Font)
+    {
         // Postscript fonts may contain more than 255 glyphs, so we end up
         // using multiple font descriptions with a glyph ordering.  Record
         // the name of each glyph.
-        info->fGlyphNames.reset(
-                new SkAutoTArray<SkString>(face->num_glyphs));
+        info->fGlyphNames.reset(new SkAutoTArray<SkString>(face->num_glyphs));
         for (int gID = 0; gID < face->num_glyphs; gID++) {
             char glyphName[128];  // PS limit for names is 127 bytes.
             FT_Get_Glyph_Name(face, gID, glyphName, 128);
@@ -645,8 +613,9 @@ SkAdvancedTypefaceMetrics* SkTypeface_FreeType::onGetAdvancedTypefaceMetrics(
     }
 
     if (perGlyphInfo & kToUnicode_PerGlyphInfo &&
-           info->fType != SkAdvancedTypefaceMetrics::kType1_Font &&
-           face->num_charmaps) {
+        info->fType != SkAdvancedTypefaceMetrics::kType1_Font &&
+        face->num_charmaps)
+    {
         populate_glyph_to_unicode(face, &(info->fGlyphToUnicode));
     }
 
diff --git a/src/ports/SkFontHost_mac.cpp b/src/ports/SkFontHost_mac.cpp
index 55eec33502..68668c248e 100644
--- a/src/ports/SkFontHost_mac.cpp
+++ b/src/ports/SkFontHost_mac.cpp
@@ -1610,29 +1610,21 @@ SkAdvancedTypefaceMetrics* SkTypeface_Mac::onGetAdvancedTypefaceMetrics(
     }
 
     if (perGlyphInfo & kHAdvance_PerGlyphInfo) {
-        if (info->fStyle & SkAdvancedTypefaceMetrics::kFixedPitch_Style) {
-            SkAdvancedTypefaceMetrics::WidthRange range(0);
-            range.fAdvance.append(1, &min_width);
-            SkAdvancedTypefaceMetrics::FinishRange(
-                    &range, 0, SkAdvancedTypefaceMetrics::WidthRange::kDefault);
-            info->fGlyphWidths.emplace_back(std::move(range));
-        } else {
-            CTFontRef borrowedCTFont = ctFont.get();
-            info->setGlyphWidths(
-                SkToInt(glyphCount),
-                glyphIDs,
-                glyphIDsCount,
-                SkAdvancedTypefaceMetrics::GetAdvance([borrowedCTFont](int gId, int16_t* data) {
-                    CGSize advance;
-                    advance.width = 0;
-                    CGGlyph glyph = gId;
-                    CTFontGetAdvancesForGlyphs(borrowedCTFont, kCTFontHorizontalOrientation,
-                                               &glyph, &advance, 1);
-                    *data = sk_float_round2int(advance.width);
-                    return true;
-                })
-            );
-        }
+        CTFontRef borrowedCTFont = ctFont.get();
+        info->setGlyphWidths(
+            SkToInt(glyphCount),
+            glyphIDs,
+            glyphIDsCount,
+            SkAdvancedTypefaceMetrics::GetAdvance([borrowedCTFont](int gId, int16_t* data) {
+                CGSize advance;
+                advance.width = 0;
+                CGGlyph glyph = gId;
+                CTFontGetAdvancesForGlyphs(borrowedCTFont, kCTFontHorizontalOrientation,
+                                           &glyph, &advance, 1);
+                *data = sk_float_round2int(advance.width);
+                return true;
+            })
+        );
     }
     return info;
 }
diff --git a/src/ports/SkFontHost_win.cpp b/src/ports/SkFontHost_win.cpp
index 34d05068f5..22262a5b71 100644
--- a/src/ports/SkFontHost_win.cpp
+++ b/src/ports/SkFontHost_win.cpp
@@ -1818,34 +1818,26 @@ SkAdvancedTypefaceMetrics* LogFontTypeface::onGetAdvancedTypefaceMetrics(
     }
 
     if (perGlyphInfo & kHAdvance_PerGlyphInfo) {
-        if (info->fStyle & SkAdvancedTypefaceMetrics::kFixedPitch_Style) {
-            SkAdvancedTypefaceMetrics::WidthRange range(0);
-            range.fAdvance.append(1, &min_width);
-            SkAdvancedTypefaceMetrics::FinishRange(
-                    &range, 0, SkAdvancedTypefaceMetrics::WidthRange::kDefault);
-            info->fGlyphWidths.emplace_back(std::move(range));
-        } else {
-            info->setGlyphWidths(
-                glyphCount,
-                glyphIDs,
-                glyphIDsCount,
-                SkAdvancedTypefaceMetrics::GetAdvance([hdc](int gId, int16_t* advance) {
-                    // Initialize the MAT2 structure to
-                    // the identify transformation matrix.
-                    static const MAT2 mat2 = {
-                        SkScalarToFIXED(1), SkScalarToFIXED(0),
-                        SkScalarToFIXED(0), SkScalarToFIXED(1)};
-                    int flags = GGO_METRICS | GGO_GLYPH_INDEX;
-                    GLYPHMETRICS gm;
-                    if (GDI_ERROR == GetGlyphOutline(hdc, gId, flags, &gm, 0, nullptr, &mat2)) {
-                        return false;
-                    }
-                    SkASSERT(advance);
-                    *advance = gm.gmCellIncX;
-                    return true;
-                })
-            );
-        }
+        info->setGlyphWidths(
+            glyphCount,
+            glyphIDs,
+            glyphIDsCount,
+            SkAdvancedTypefaceMetrics::GetAdvance([hdc](int gId, int16_t* advance) {
+                // Initialize the MAT2 structure to
+                // the identify transformation matrix.
+                static const MAT2 mat2 = {
+                    SkScalarToFIXED(1), SkScalarToFIXED(0),
+                    SkScalarToFIXED(0), SkScalarToFIXED(1)};
+                int flags = GGO_METRICS | GGO_GLYPH_INDEX;
+                GLYPHMETRICS gm;
+                if (GDI_ERROR == GetGlyphOutline(hdc, gId, flags, &gm, 0, nullptr, &mat2)) {
+                    return false;
+                }
+                SkASSERT(advance);
+                *advance = gm.gmCellIncX;
+                return true;
+            })
+        );
     }
 
 Error: