Merge pull request #190 from grigorig/fonts

Substitutions and some fixes

7 files changed, 144 insertions, 44 deletions

diff --git a/libass/ass_coretext.c b/libass/ass_coretext.c
index 3553324..877018d 100644
--- a/libass/ass_coretext.c
+++ b/libass/ass_coretext.c
@@ -25,6 +25,12 @@
 
 #define SAFE_CFRelease(x) do { if (x) CFRelease(x); } while(0)
 
+static const ASS_FontMapping font_substitutions[] = {
+    {"sans-serif", "Helvetica"},
+    {"serif", "Times"},
+    {"monospace", "Courier"}
+};
+
 static char *cfstr2buf(CFStringRef string)
 {
     const int encoding = kCFStringEncodingUTF8;
@@ -266,10 +272,18 @@ static char *get_fallback(void *priv, const char *family, uint32_t codepoint)
     return res_family;
 }
 
+static void get_substitutions(void *priv, const char *name,
+                              ASS_FontProviderMetaData *meta)
+{
+    const int n = sizeof(font_substitutions) / sizeof(font_substitutions[0]);
+    ass_map_font(font_substitutions, n, name, meta);
+}
+
 static ASS_FontProviderFuncs coretext_callbacks = {
     .check_glyph        = check_glyph,
     .destroy_font       = destroy_font,
     .match_fonts        = match_fonts,
+    .get_substitutions  = get_substitutions,
     .get_fallback       = get_fallback,
 };
 
diff --git a/libass/ass_directwrite.c b/libass/ass_directwrite.c
index 86b0b4b..f11deb6 100644
--- a/libass/ass_directwrite.c
+++ b/libass/ass_directwrite.c
@@ -31,6 +31,12 @@
 #define NAME_MAX_LENGTH 256
 #define FALLBACK_DEFAULT_FONT L"Arial"
 
+static const ASS_FontMapping font_substitutions[] = {
+    {"sans-serif", "Arial"},
+    {"serif", "Times New Roman"},
+    {"monospace", "Courier New"}
+};
+
 /*
  * The private data stored for every font, detected by this backend.
  */
@@ -624,6 +630,13 @@ static void scan_fonts(IDWriteFactory *factory,
     }
 }
 
+static void get_substitutions(void *priv, const char *name,
+                              ASS_FontProviderMetaData *meta)
+{
+    const int n = sizeof(font_substitutions) / sizeof(font_substitutions[0]);
+    ass_map_font(font_substitutions, n, name, meta);
+}
+
 /*
  * Called by libass when the provider should perform the
  * specified task
@@ -633,6 +646,7 @@ static ASS_FontProviderFuncs directwrite_callbacks = {
     .check_glyph        = check_glyph,
     .destroy_font       = destroy_font,
     .destroy_provider   = destroy_provider,
+    .get_substitutions  = get_substitutions,
     .get_fallback       = get_fallback,
 };
 
diff --git a/libass/ass_font.c b/libass/ass_font.c
index 0164b67..b3c639d 100644
--- a/libass/ass_font.c
+++ b/libass/ass_font.c
@@ -153,7 +153,6 @@ static int add_face(ASS_FontSelector *fontsel, ASS_Font *font, uint32_t ch)
         if (font->faces_uid[i] == uid) {
             ass_msg(font->library, MSGL_INFO,
                     "Got a font face that already is available! Skipping.");
-            free(path);
             return i;
         }
     }
@@ -178,7 +177,6 @@ static int add_face(ASS_FontSelector *fontsel, ASS_Font *font, uint32_t ch)
         if (error) {
             ass_msg(font->library, MSGL_WARN,
                     "Error opening memory font: '%s'", path);
-            free(path);
             return -1;
         }
 
@@ -187,7 +185,6 @@ static int add_face(ASS_FontSelector *fontsel, ASS_Font *font, uint32_t ch)
         if (error) {
             ass_msg(font->library, MSGL_WARN,
                     "Error opening font: '%s', %d", path, index);
-            free(path);
             return -1;
         }
 
@@ -201,7 +198,6 @@ static int add_face(ASS_FontSelector *fontsel, ASS_Font *font, uint32_t ch)
                 if (error) {
                     ass_msg(font->library, MSGL_WARN,
                             "Error opening font: '%s', %d", path, i);
-                    free(path);
                     return -1;
                 }
 
@@ -217,7 +213,6 @@ static int add_face(ASS_FontSelector *fontsel, ASS_Font *font, uint32_t ch)
     font->faces[font->n_faces] = face;
     font->faces_uid[font->n_faces++] = uid;
     ass_face_set_size(face, font->size);
-    free(path);
     return font->n_faces - 1;
 }
 
diff --git a/libass/ass_fontconfig.c b/libass/ass_fontconfig.c
index e97102b..184f090 100644
--- a/libass/ass_fontconfig.c
+++ b/libass/ass_fontconfig.c
@@ -177,6 +177,17 @@ static char *get_fallback(void *priv, const char *family, uint32_t codepoint)
     if (!fc->fallbacks || fc->fallbacks->nfont == 0)
         return NULL;
 
+    if (codepoint == 0) {
+        char *family = NULL;
+        result = FcPatternGetString(fc->fallbacks->fonts[0], FC_FAMILY, 0,
+                (FcChar8 **)&family);
+        if (result == FcResultMatch) {
+            return strdup(family);
+        } else {
+            return NULL;
+        }
+    }
+
     // fallback_chars is the union of all available charsets, so
     // if we can't find the glyph in there, the system does not
     // have any font to render this glyph.
@@ -194,8 +205,11 @@ static char *get_fallback(void *priv, const char *family, uint32_t codepoint)
             char *family = NULL;
             result = FcPatternGetString(pattern, FC_FAMILY, 0,
                     (FcChar8 **)&family);
-            family = strdup(family);
-            return family;
+            if (result == FcResultMatch) {
+                return strdup(family);
+            } else {
+                return NULL;
+            }
         }
     }
 
@@ -275,6 +289,7 @@ ass_fontconfig_add_provider(ASS_Library *lib, ASS_FontSelector *selector,
         ass_msg(lib, MSGL_FATAL,
                 "No valid fontconfig configuration found!");
         FcConfigDestroy(fc->config);
+        free(fc);
         return NULL;
     }
 
diff --git a/libass/ass_fontselect.c b/libass/ass_fontselect.c
index 95d8c95..d48b170 100644
--- a/libass/ass_fontselect.c
+++ b/libass/ass_fontselect.c
@@ -477,41 +477,19 @@ static int check_glyph(ASS_FontInfo *fi, uint32_t code)
     return provider->funcs.check_glyph(fi->priv, code);
 }
 
-static char *select_font(ASS_FontSelector *priv, ASS_Library *library,
-                         const char *family, unsigned bold, unsigned italic,
-                         int *index, char **postscript_name, int *uid,
-                         ASS_FontStream *stream, uint32_t code)
+static char *
+find_font(ASS_FontSelector *priv, ASS_Library *library,
+          ASS_FontProviderMetaData meta, unsigned bold, unsigned italic,
+          int *index, char **postscript_name, int *uid, ASS_FontStream *stream,
+          uint32_t code, bool *name_match)
 {
     ASS_FontInfo req = {0};
-    char *family_trim = strdup_trimmed(family);
-    ASS_FontProvider *default_provider = priv->default_provider;
-    ASS_FontProviderMetaData meta = {0};
     ASS_FontInfo *selected = NULL;
 
-    if (family_trim == NULL)
-        return NULL;
-
-    if (default_provider && default_provider->funcs.match_fonts)
-        default_provider->funcs.match_fonts(library, default_provider, family_trim);
-
     // do we actually have any fonts?
     if (!priv->n_font)
         return NULL;
 
-    ASS_FontProviderMetaData default_meta = {
-        .n_fullname = 1,
-        .fullnames  = &family_trim,
-    };
-
-    // get a list of substitutes if applicable, and use it for matching
-    if (default_provider && default_provider->funcs.get_substitutions) {
-        default_provider->funcs.get_substitutions(default_provider->priv,
-                                                  family_trim, &meta);
-    }
-    if (!meta.n_fullname) {
-        meta = default_meta;
-    }
-
     // fill font request
     req.slant   = italic;
     req.weight  = bold;
@@ -530,11 +508,13 @@ static char *select_font(ASS_FontSelector *priv, ASS_Library *library,
                 // If there's a family match, compare font attributes
                 // to determine best match in that particular family
                 score = font_attributes_similarity(font, &req);
+                *name_match = true;
             } else if (matches_fullname(font, fullname)) {
                 // If we don't have any match, compare fullnames against request
                 // if there is a match now, assign lowest score possible. This means
                 // the font should be chosen instantly, without further search.
                 score = 0;
+                *name_match = true;
             }
 
             // Consider updating idx if score is better than current minimum
@@ -580,13 +560,68 @@ static char *select_font(ASS_FontSelector *priv, ASS_Library *library,
             ASS_FontProvider *provider = selected->provider;
             stream->func = provider->funcs.get_data;
             stream->priv = selected->priv;
-            // FIXME: we should define a default family name in some way,
-            // possibly the first (or last) English name
-            result = strdup(selected->families[0]);
+            // Prefer PostScript name because it is unique. This is only
+            // used for display purposes so it doesn't matter that much,
+            // though.
+            if (selected->postscript_name)
+                result = selected->postscript_name;
+            else
+                result = selected->families[0];
         } else
-            result = strdup(selected->path);
+            result = selected->path;
+    }
+
+    return result;
+}
+
+static char *select_font(ASS_FontSelector *priv, ASS_Library *library,
+                         const char *family, unsigned bold, unsigned italic,
+                         int *index, char **postscript_name, int *uid,
+                         ASS_FontStream *stream, uint32_t code)
+{
+    ASS_FontProvider *default_provider = priv->default_provider;
+    ASS_FontProviderMetaData meta = {0};
+    char *family_trim = strdup_trimmed(family);
+    char *result = NULL;
+    bool name_match = false;
+
+    if (family_trim == NULL)
+        return NULL;
+
+    ASS_FontProviderMetaData default_meta = {
+        .n_fullname = 1,
+        .fullnames  = &family_trim,
+    };
+
+    // Get a list of substitutes if applicable, and use it for matching.
+    if (default_provider && default_provider->funcs.get_substitutions) {
+        default_provider->funcs.get_substitutions(default_provider->priv,
+                                                  family_trim, &meta);
+    }
+
+    if (!meta.n_fullname) {
+        meta = default_meta;
     }
 
+    result = find_font(priv, library, meta, bold, italic, index,
+                       postscript_name, uid, stream, code, &name_match);
+
+    // If no matching font was found, it might not exist in the font list
+    // yet. Call the match_fonts callback to fill in the missing fonts
+    // on demand, and retry the search for a match.
+    if (result == NULL && name_match == false && default_provider &&
+            default_provider->funcs.match_fonts) {
+        // TODO: consider changing the API to make more efficient
+        // implementations possible.
+        for (int i = 0; i < meta.n_fullname; i++) {
+            default_provider->funcs.match_fonts(library, default_provider,
+                                                meta.fullnames[i]);
+        }
+        result = find_font(priv, library, meta, bold, italic, index,
+                           postscript_name, uid, stream, code, &name_match);
+    }
+
+    // cleanup
     free(family_trim);
     if (meta.fullnames != default_meta.fullnames) {
         for (int i = 0; i < meta.n_fullname; i++)
@@ -637,7 +672,7 @@ char *ass_font_select(ASS_FontSelector *priv, ASS_Library *library,
         if (!search_family || !*search_family)
             search_family = "Arial";
         char *fallback_family = default_provider->funcs.get_fallback(
-                default_provider->priv, family, code);
+                default_provider->priv, search_family, code);
 
         if (fallback_family) {
             res = select_font(priv, library, fallback_family, bold, italic,
@@ -1000,10 +1035,6 @@ void ass_fontselect_free(ASS_FontSelector *priv)
     if (priv->embedded_provider)
         ass_font_provider_free(priv->embedded_provider);
 
-    // XXX: not quite sure, maybe we should track all registered
-    // providers and free them right here. or should that be the
-    // responsibility of the library user?
-
     free(priv->font_infos);
     free(priv->path_default);
     free(priv->family_default);
diff --git a/libass/ass_fontselect.h b/libass/ass_fontselect.h
index c989e1a..1e0959e 100644
--- a/libass/ass_fontselect.h
+++ b/libass/ass_fontselect.h
@@ -177,6 +177,37 @@ struct ass_font_stream {
     void *priv;
 };
 
+
+typedef struct ass_font_mapping ASS_FontMapping;
+
+struct ass_font_mapping {
+    const char *from;
+    const char *to;
+};
+
+/**
+ * Simple font substitution helper. This can be used to implement basic
+ * mappings from one name to another. This is useful for supporting
+ * generic font families in font providers.
+ *
+ * \param map list of mappings
+ * \param len length of list of mappings
+ * \param name font name to map from
+ * \param meta metadata struct, mapped fonts will be stored into this
+ */
+inline void ass_map_font(const ASS_FontMapping *map, int len, const char *name,
+                         ASS_FontProviderMetaData *meta)
+{
+    for (int i = 0; i < len; i++) {
+        if (strcasecmp(map[i].from, name) == 0) {
+            meta->n_fullname = 1;
+            meta->fullnames = calloc(1, sizeof(char *));
+            meta->fullnames[0] = strdup(map[i].to);
+            return;
+        }
+    }
+}
+
 ASS_FontSelector *
 ass_fontselect_init(ASS_Library *library,
                     FT_Library ftlibrary, const char *family,
diff --git a/test/test.c b/test/test.c
index 175e8be..4884b28 100644
--- a/test/test.c
+++ b/test/test.c
@@ -107,7 +107,7 @@ static void init(int frame_w, int frame_h)
     }
 
     ass_set_frame_size(ass_renderer, frame_w, frame_h);
-    ass_set_fonts(ass_renderer, NULL, "Sans",
+    ass_set_fonts(ass_renderer, NULL, "sans-serif",
                   ASS_FONTPROVIDER_AUTODETECT, NULL, 1);
 }