Begin switch to SkFontStyle for legacy calls.

src/ports/SkFontConfigInterface_direct.cpp

 /*
  * Copyright 2009-2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /* migrated from chrome/src/skia/ext/SkFontHost_fontconfig_direct.cpp */
 
 #include "SkBuffer.h"
 #include "SkDataTable.h"
+#include "SkFixed.h"
 #include "SkFontConfigInterface_direct.h"
 #include "SkFontStyle.h"
 #include "SkMutex.h"
 #include "SkStream.h"
 #include "SkString.h"
 #include "SkTArray.h"
 #include "SkTDArray.h"
 #include "SkTemplates.h"
 #include "SkTypeface.h"
 #include "SkTypes.h"
@@ skipping 275 matching lines @@
 // tells you whether a given request is for such a fallback.
 bool IsFallbackFontAllowed(const SkString& family) {
   const char* family_cstr = family.c_str();
   return family.isEmpty() ||
          strcasecmp(family_cstr, "sans") == 0 ||
          strcasecmp(family_cstr, "serif") == 0 ||
          strcasecmp(family_cstr, "monospace") == 0;
 }
 
 // Retrieves |is_bold|, |is_italic| and |font_family| properties from |font|.
+#ifdef SK_VERY_LEGACY_CREATE_TYPEFACE
 SkTypeface::Style GetFontStyle(FcPattern* font) {
     int resulting_bold;
     if (FcPatternGetInteger(font, FC_WEIGHT, 0, &resulting_bold))
         resulting_bold = FC_WEIGHT_NORMAL;
 
     int resulting_italic;
     if (FcPatternGetInteger(font, FC_SLANT, 0, &resulting_italic))
         resulting_italic = FC_SLANT_ROMAN;
 
     // If we ask for an italic font, fontconfig might take a roman font and set
@@ skipping 11 matching lines @@
     int styleBits = 0;
     if (resulting_bold > FC_WEIGHT_MEDIUM && !have_embolden) {
         styleBits |= SkTypeface::kBold;
     }
     if (resulting_italic > FC_SLANT_ROMAN && !have_matrix) {
         styleBits |= SkTypeface::kItalic;
     }
 
     return (SkTypeface::Style)styleBits;
 }
+#else
+
+static int get_int(FcPattern* pattern, const char object[], int missing) {
+    int value;
+    if (FcPatternGetInteger(pattern, object, 0, &value) != FcResultMatch) {
+        return missing;
+    }
+    return value;
+}
+
+static int map_range(SkFixed value,
+                     SkFixed old_min, SkFixed old_max,
+                     SkFixed new_min, SkFixed new_max)
+{
+    SkASSERT(old_min < old_max);
+    SkASSERT(new_min <= new_max);
+    return new_min + SkMulDiv(value - old_min, new_max - new_min, old_max - old_min);
+}
+
+static int ave(SkFixed a, SkFixed b) {
+    return SkFixedAve(a, b);
+}
+
+struct MapRanges {
+    SkFixed old_val;
+    SkFixed new_val;
+};
+
+static SkFixed map_ranges_fixed(SkFixed val, MapRanges const ranges[], int rangesCount) {
+    // -Inf to [0]
+    if (val < ranges[0].old_val) {
+        return ranges[0].new_val;
+    }
+
+    // Linear from [i] to ave([i], [i+1]), then from ave([i], [i+1]) to [i+1]
+    for (int i = 0; i < rangesCount - 1; ++i) {
+        if (val < ave(ranges[i].old_val, ranges[i+1].old_val)) {

[dogben, 2016/04/11 20:28:58]

I think you would get the same result if you just do:
        if (val < ranges[i+1].old_val) {
            return map_range(val, ranges[i].old_val, ranges[i+1].old_val,
                                  ranges[i].new_val, ranges[i+1].new_val);
        }

It's all linear between the specified points.

Unless you're trying to linearize between the midpoints, which seems wrong.

[bungeman-skia, 2016/04/11 21:55:52]

This was all copy-pasted from somewhere else, but I think you're right. Mostly
from the argument that we're linearly interpolating, but we only have two
points, so what else was going to happen?

Done.

+            return map_range(val, ranges[i].old_val, ave(ranges[i].old_val, ranges[i+1].old_val),
+                                  ranges[i].new_val, ave(ranges[i].new_val, ranges[i+1].new_val));
+        }
+        if (val < ranges[i+1].old_val) {
+            return map_range(val, ave(ranges[i].old_val, ranges[i+1].old_val), ranges[i+1].old_val,
+                                  ave(ranges[i].new_val, ranges[i+1].new_val), ranges[i+1].new_val);
+        }
+    }
+
+    // From [n] to +Inf
+    // if (fcweight < Inf)
+    return ranges[rangesCount-1].new_val;
+}
+
+static int map_ranges(int val, MapRanges const ranges[], int rangesCount) {
+    return SkFixedRoundToInt(map_ranges_fixed(SkIntToFixed(val), ranges, rangesCount));
+}
+
+template<int n> struct SkTFixed {
+    static_assert(-32768 <= n && n <= 32767, "SkTFixed_n_not_in_range");
+    static const SkFixed value = static_cast<SkFixed>(n << 16);
+};
+
+static SkFontStyle skfontstyle_from_fcpattern(FcPattern* pattern) {
+    typedef SkFontStyle SkFS;
+
+    static const MapRanges weightRanges[] = {
+        { SkTFixed<FC_WEIGHT_THIN>::value,       SkTFixed<SkFS::kThin_Weight>::value },
+        { SkTFixed<FC_WEIGHT_EXTRALIGHT>::value, SkTFixed<SkFS::kExtraLight_Weight>::value },
+        { SkTFixed<FC_WEIGHT_LIGHT>::value,      SkTFixed<SkFS::kLight_Weight>::value },
+        { SkTFixed<FC_WEIGHT_REGULAR>::value,    SkTFixed<SkFS::kNormal_Weight>::value },
+        { SkTFixed<FC_WEIGHT_MEDIUM>::value,     SkTFixed<SkFS::kMedium_Weight>::value },
+        { SkTFixed<FC_WEIGHT_DEMIBOLD>::value,   SkTFixed<SkFS::kSemiBold_Weight>::value },
+        { SkTFixed<FC_WEIGHT_BOLD>::value,       SkTFixed<SkFS::kBold_Weight>::value },
+        { SkTFixed<FC_WEIGHT_EXTRABOLD>::value,  SkTFixed<SkFS::kExtraBold_Weight>::value },
+        { SkTFixed<FC_WEIGHT_BLACK>::value,      SkTFixed<SkFS::kBlack_Weight>::value },
+        { SkTFixed<FC_WEIGHT_EXTRABLACK>::value, SkTFixed<1000>::value },
+    };
+    int weight = map_ranges(get_int(pattern, FC_WEIGHT, FC_WEIGHT_REGULAR),
+                            weightRanges, SK_ARRAY_COUNT(weightRanges));
+
+    static const MapRanges widthRanges[] = {
+        { SkTFixed<FC_WIDTH_ULTRACONDENSED>::value, SkTFixed<SkFS::kUltraCondensed_Width>::value },
+        { SkTFixed<FC_WIDTH_EXTRACONDENSED>::value, SkTFixed<SkFS::kExtraCondensed_Width>::value },
+        { SkTFixed<FC_WIDTH_CONDENSED>::value,      SkTFixed<SkFS::kCondensed_Width>::value },
+        { SkTFixed<FC_WIDTH_SEMICONDENSED>::value,  SkTFixed<SkFS::kSemiCondensed_Width>::value },
+        { SkTFixed<FC_WIDTH_NORMAL>::value,         SkTFixed<SkFS::kNormal_Width>::value },
+        { SkTFixed<FC_WIDTH_SEMIEXPANDED>::value,   SkTFixed<SkFS::kSemiExpanded_Width>::value },
+        { SkTFixed<FC_WIDTH_EXPANDED>::value,       SkTFixed<SkFS::kExpanded_Width>::value },
+        { SkTFixed<FC_WIDTH_EXTRAEXPANDED>::value,  SkTFixed<SkFS::kExtraExpanded_Width>::value },
+        { SkTFixed<FC_WIDTH_ULTRAEXPANDED>::value,  SkTFixed<SkFS::kUltaExpanded_Width>::value },
+    };
+    int width = map_ranges(get_int(pattern, FC_WIDTH, FC_WIDTH_NORMAL),
+                           widthRanges, SK_ARRAY_COUNT(widthRanges));
+
+    SkFS::Slant slant = get_int(pattern, FC_SLANT, FC_SLANT_ROMAN) > 0
+                             ? SkFS::kItalic_Slant
+                             : SkFS::kUpright_Slant;
+
+    return SkFontStyle(weight, width, slant);
+}
+
+static void fcpattern_from_skfontstyle(SkFontStyle style, FcPattern* pattern) {
+    typedef SkFontStyle SkFS;
+
+    static const MapRanges weightRanges[] = {
+        { SkTFixed<SkFS::kThin_Weight>::value,       SkTFixed<FC_WEIGHT_THIN>::value },
+        { SkTFixed<SkFS::kExtraLight_Weight>::value, SkTFixed<FC_WEIGHT_EXTRALIGHT>::value },
+        { SkTFixed<SkFS::kLight_Weight>::value,      SkTFixed<FC_WEIGHT_LIGHT>::value },
+        { SkTFixed<SkFS::kNormal_Weight>::value,     SkTFixed<FC_WEIGHT_REGULAR>::value },
+        { SkTFixed<SkFS::kMedium_Weight>::value,     SkTFixed<FC_WEIGHT_MEDIUM>::value },
+        { SkTFixed<SkFS::kSemiBold_Weight>::value,   SkTFixed<FC_WEIGHT_DEMIBOLD>::value },
+        { SkTFixed<SkFS::kBold_Weight>::value,       SkTFixed<FC_WEIGHT_BOLD>::value },
+        { SkTFixed<SkFS::kExtraBold_Weight>::value,  SkTFixed<FC_WEIGHT_EXTRABOLD>::value },
+        { SkTFixed<SkFS::kBlack_Weight>::value,      SkTFixed<FC_WEIGHT_BLACK>::value },
+        { SkTFixed<1000>::value,                     SkTFixed<FC_WEIGHT_EXTRABLACK>::value },
+    };
+    int weight = map_ranges(style.weight(), weightRanges, SK_ARRAY_COUNT(weightRanges));
+
+    static const MapRanges widthRanges[] = {
+        { SkTFixed<SkFS::kUltraCondensed_Width>::value, SkTFixed<FC_WIDTH_ULTRACONDENSED>::value },
+        { SkTFixed<SkFS::kExtraCondensed_Width>::value, SkTFixed<FC_WIDTH_EXTRACONDENSED>::value },
+        { SkTFixed<SkFS::kCondensed_Width>::value,      SkTFixed<FC_WIDTH_CONDENSED>::value },
+        { SkTFixed<SkFS::kSemiCondensed_Width>::value,  SkTFixed<FC_WIDTH_SEMICONDENSED>::value },
+        { SkTFixed<SkFS::kNormal_Width>::value,         SkTFixed<FC_WIDTH_NORMAL>::value },
+        { SkTFixed<SkFS::kSemiExpanded_Width>::value,   SkTFixed<FC_WIDTH_SEMIEXPANDED>::value },
+        { SkTFixed<SkFS::kExpanded_Width>::value,       SkTFixed<FC_WIDTH_EXPANDED>::value },
+        { SkTFixed<SkFS::kExtraExpanded_Width>::value,  SkTFixed<FC_WIDTH_EXTRAEXPANDED>::value },
+        { SkTFixed<SkFS::kUltaExpanded_Width>::value,   SkTFixed<FC_WIDTH_ULTRAEXPANDED>::value },
+    };
+    int width = map_ranges(style.width(), widthRanges, SK_ARRAY_COUNT(widthRanges));
+
+    FcPatternAddInteger(pattern, FC_WEIGHT, weight);
+    FcPatternAddInteger(pattern, FC_WIDTH, width);
+    FcPatternAddInteger(pattern, FC_SLANT, style.isItalic() ? FC_SLANT_ITALIC : FC_SLANT_ROMAN);
+}
+
+SkFontStyle GetFontStyle(FcPattern* font) {
+    return skfontstyle_from_fcpattern(font);
+}
+#endif
 
 }  // anonymous namespace
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #define kMaxFontFamilyLength    2048
 
 SkFontConfigInterfaceDirect::SkFontConfigInterfaceDirect() {
     SkAutoMutexAcquire ac(mutex_);
 
@@ skipping 62 matching lines @@
       if (acceptable_substitute)
         break;
     }
     if (!acceptable_substitute)
       return nullptr;
   }
 
   return match;
 }
 
+#ifdef SK_VERY_LEGACY_CREATE_TYPEFACE
 bool SkFontConfigInterfaceDirect::matchFamilyName(const char familyName[],
                                                   SkTypeface::Style style,
                                                   FontIdentity* outIdentity,
                                                   SkString* outFamilyName,
                                                   SkTypeface::Style* outStyle) {
+#else
+bool SkFontConfigInterfaceDirect::matchFamilyName(const char familyName[],
+                                                  SkFontStyle style,
+                                                  FontIdentity* outIdentity,
+                                                  SkString* outFamilyName,
+                                                  SkFontStyle* outStyle) {
+#endif
     SkString familyStr(familyName ? familyName : "");
     if (familyStr.size() > kMaxFontFamilyLength) {
         return false;
     }
 
     SkAutoMutexAcquire ac(mutex_);
 
     FcPattern* pattern = FcPatternCreate();
 
     if (familyName) {
         FcPatternAddString(pattern, FC_FAMILY, (FcChar8*)familyName);
     }
+#ifdef SK_VERY_LEGACY_CREATE_TYPEFACE
     FcPatternAddInteger(pattern, FC_WEIGHT,
                         (style & SkTypeface::kBold) ? FC_WEIGHT_BOLD
                                                     : FC_WEIGHT_NORMAL);
     FcPatternAddInteger(pattern, FC_SLANT,
                         (style & SkTypeface::kItalic) ? FC_SLANT_ITALIC
                                                       : FC_SLANT_ROMAN);
+#else
+    fcpattern_from_skfontstyle(style, pattern);
+#endif
+
     FcPatternAddBool(pattern, FC_SCALABLE, FcTrue);
 
     FcConfigSubstitute(nullptr, pattern, FcMatchPattern);
     FcDefaultSubstitute(pattern);
 
     // Font matching:
     // CSS often specifies a fallback list of families:
     //    font-family: a, b, c, serif;
     // However, fontconfig will always do its best to find *a* font when asked
     // for something so we need a way to tell if the match which it has found is
@@ skipping 122 matching lines @@
         const char* famName = get_name(match, FC_FAMILY);
         if (famName && !find_name(names, famName)) {
             *names.append() = famName;
             *sizes.append() = strlen(famName) + 1;
         }
     }
 
     return SkDataTable::NewCopyArrays((const void*const*)names.begin(),
                                       sizes.begin(), names.count());
 }