[font] Use freetype instead of Pillow for font rendering (#8300)

esphome/components/font/__init__.py

@@ -1,3 +1,4 @@
+from collections.abc import MutableMapping
 import functools
 import hashlib
 import logging
@@ -6,10 +7,10 @@ from pathlib import Path
 import re
 
 import esphome_glyphsets as glyphsets
-import freetype
+from freetype import Face, ft_pixel_mode_grays, ft_pixel_mode_mono
 import requests
 
-from esphome import core, external_files
+from esphome import external_files
 import esphome.codegen as cg
 import esphome.config_validation as cv
 from esphome.const import (
@@ -26,7 +27,7 @@ from esphome.const import (
     CONF_WEIGHT,
 )
 from esphome.core import CORE, HexInt
-from esphome.helpers import copy_file_if_changed, cpp_string_escape
+from esphome.helpers import cpp_string_escape
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -49,13 +50,42 @@ CONF_IGNORE_MISSING_GLYPHS = "ignore_missing_glyphs"
 
 
 # Cache loaded freetype fonts
-class FontCache(dict):
+class FontCache(MutableMapping):
-    def __missing__(self, key):
+    @staticmethod
-        try:
+    def get_name(value):
-            res = self[key] = freetype.Face(key)
+        if CONF_FAMILY in value:
-            return res
+            return (
-        except freetype.FT_Exception as e:
+                f"{value[CONF_FAMILY]}:{int(value[CONF_ITALIC])}:{value[CONF_WEIGHT]}"
-            raise cv.Invalid(f"Could not load Font file {key}: {e}") from e
+            )
+        if CONF_URL in value:
+            return value[CONF_URL]
+        return value[CONF_PATH]
+
+    @staticmethod
+    def _keytransform(value):
+        if CONF_FAMILY in value:
+            return f"gfont:{value[CONF_FAMILY]}:{int(value[CONF_ITALIC])}:{value[CONF_WEIGHT]}"
+        if CONF_URL in value:
+            return f"url:{value[CONF_URL]}"
+        return f"file:{value[CONF_PATH]}"
+
+    def __init__(self):
+        self.store = {}
+
+    def __delitem__(self, key):
+        del self.store[self._keytransform(key)]
+
+    def __iter__(self):
+        return iter(self.store)
+
+    def __len__(self):
+        return len(self.store)
+
+    def __getitem__(self, item):
+        return self.store[self._keytransform(item)]
+
+    def __setitem__(self, key, value):
+        self.store[self._keytransform(key)] = Face(str(value))
 
 
 FONT_CACHE = FontCache()
@@ -109,14 +139,14 @@ def check_missing_glyphs(file, codepoints, warning: bool = False):
         )
         if count > 10:
             missing_str += f"\n    and {count - 10} more."
-        message = f"Font {Path(file).name} is missing {count} glyph{'s' if count != 1 else ''}:\n    {missing_str}"
+        message = f"Font {FontCache.get_name(file)} is missing {count} glyph{'s' if count != 1 else ''}:\n    {missing_str}"
         if warning:
             _LOGGER.warning(message)
         else:
             raise cv.Invalid(message)
 
 
-def validate_glyphs(config):
+def validate_font_config(config):
     """
     Check for duplicate codepoints, then check that all requested codepoints actually
     have glyphs defined in the appropriate font file.
@@ -143,8 +173,6 @@ def validate_glyphs(config):
     # Make setpoints and glyphspoints disjoint
     setpoints.difference_update(glyphspoints)
     if fileconf[CONF_TYPE] == TYPE_LOCAL_BITMAP:
-        # Pillow only allows 256 glyphs per bitmap font. Not sure if that is a Pillow limitation
-        # or a file format limitation
         if any(x >= 256 for x in setpoints.copy().union(glyphspoints)):
             raise cv.Invalid("Codepoints in bitmap fonts must be in the range 0-255")
     else:
@@ -154,13 +182,14 @@ def validate_glyphs(config):
             points = {ord(x) for x in flatten(extra[CONF_GLYPHS])}
             glyphspoints.difference_update(points)
             setpoints.difference_update(points)
-            check_missing_glyphs(extra[CONF_FILE][CONF_PATH], points)
+            check_missing_glyphs(extra[CONF_FILE], points)
 
         # A named glyph that can't be provided is an error
-        check_missing_glyphs(fileconf[CONF_PATH], glyphspoints)
+
+        check_missing_glyphs(fileconf, glyphspoints)
         # A missing glyph from a set is a warning.
         if not config[CONF_IGNORE_MISSING_GLYPHS]:
-            check_missing_glyphs(fileconf[CONF_PATH], setpoints, warning=True)
+            check_missing_glyphs(fileconf, setpoints, warning=True)
 
     # Populate the default after the above checks so that use of the default doesn't trigger errors
     if not config[CONF_GLYPHS] and not config[CONF_GLYPHSETS]:
@@ -168,17 +197,32 @@ def validate_glyphs(config):
             config[CONF_GLYPHS] = [DEFAULT_GLYPHS]
         else:
             # set a default glyphset, intersected with what the font actually offers
-            font = FONT_CACHE[fileconf[CONF_PATH]]
+            font = FONT_CACHE[fileconf]
             config[CONF_GLYPHS] = [
                 chr(x)
                 for x in glyphsets.unicodes_per_glyphset(DEFAULT_GLYPHSET)
                 if font.get_char_index(x) != 0
             ]
 
+    if config[CONF_FILE][CONF_TYPE] == TYPE_LOCAL_BITMAP:
+        if CONF_SIZE in config:
+            raise cv.Invalid(
+                "Size is not a valid option for bitmap fonts, which are inherently fixed size"
+            )
+    elif CONF_SIZE not in config:
+        config[CONF_SIZE] = 20
+
     return config
 
 
 FONT_EXTENSIONS = (".ttf", ".woff", ".otf")
+BITMAP_EXTENSIONS = (".bdf", ".pcf")
+
+
+def validate_bitmap_file(value):
+    if not any(map(value.lower().endswith, BITMAP_EXTENSIONS)):
+        raise cv.Invalid(f"Only {', '.join(BITMAP_EXTENSIONS)} files are supported.")
+    return CORE.relative_config_path(cv.file_(value))
 
 
 def validate_truetype_file(value):
@@ -187,24 +231,40 @@ def validate_truetype_file(value):
             f"Please unzip the font archive '{value}' first and then use the .ttf files inside."
         )
     if not any(map(value.lower().endswith, FONT_EXTENSIONS)):
-        raise cv.Invalid(f"Only {FONT_EXTENSIONS} files are supported.")
+        raise cv.Invalid(f"Only {', '.join(FONT_EXTENSIONS)} files are supported.")
     return CORE.relative_config_path(cv.file_(value))
 
 
+def add_local_file(value):
+    if value in FONT_CACHE:
+        return value
+    path = value[CONF_PATH]
+    if not os.path.isfile(path):
+        raise cv.Invalid(f"File '{path}' not found.")
+    FONT_CACHE[value] = path
+    return value
+
+
 TYPE_LOCAL = "local"
 TYPE_LOCAL_BITMAP = "local_bitmap"
 TYPE_GFONTS = "gfonts"
 TYPE_WEB = "web"
-LOCAL_SCHEMA = cv.Schema(
+LOCAL_SCHEMA = cv.All(
+    cv.Schema(
         {
             cv.Required(CONF_PATH): validate_truetype_file,
         }
+    ),
+    add_local_file,
 )
 
-LOCAL_BITMAP_SCHEMA = cv.Schema(
+LOCAL_BITMAP_SCHEMA = cv.All(
+    cv.Schema(
         {
-        cv.Required(CONF_PATH): cv.file_,
+            cv.Required(CONF_PATH): validate_bitmap_file,
         }
+    ),
+    add_local_file,
 )
 
 FULLPATH_SCHEMA = cv.maybe_simple_value(
@@ -235,27 +295,23 @@ def _compute_local_font_path(value: dict) -> Path:
     h.update(url.encode())
     key = h.hexdigest()[:8]
     base_dir = external_files.compute_local_file_dir(DOMAIN)
-    _LOGGER.debug("_compute_local_font_path: base_dir=%s", base_dir / key)
+    _LOGGER.debug("_compute_local_font_path: %s", base_dir / key)
     return base_dir / key
 
 
-def get_font_path(value, font_type) -> Path:
-    if font_type == TYPE_GFONTS:
-        name = f"{value[CONF_FAMILY]}@{value[CONF_WEIGHT]}@{value[CONF_ITALIC]}@v1"
-        return external_files.compute_local_file_dir(DOMAIN) / f"{name}.ttf"
-    if font_type == TYPE_WEB:
-        return _compute_local_font_path(value) / "font.ttf"
-    assert False
-
-
 def download_gfont(value):
+    if value in FONT_CACHE:
+        return value
     name = (
         f"{value[CONF_FAMILY]}:ital,wght@{int(value[CONF_ITALIC])},{value[CONF_WEIGHT]}"
     )
     url = f"https://fonts.googleapis.com/css2?family={name}"
-    path = get_font_path(value, TYPE_GFONTS)
+    path = (
+        external_files.compute_local_file_dir(DOMAIN)
+        / f"{value[CONF_FAMILY]}@{value[CONF_WEIGHT]}@{value[CONF_ITALIC]}@v1.ttf"
+    )
+    if not external_files.is_file_recent(str(path), value[CONF_REFRESH]):
         _LOGGER.debug("download_gfont: path=%s", path)
-
         try:
             req = requests.get(url, timeout=external_files.NETWORK_TIMEOUT)
             req.raise_for_status()
@@ -275,16 +331,23 @@ def download_gfont(value):
         _LOGGER.debug("download_gfont: ttf_url=%s", ttf_url)
 
         external_files.download_content(ttf_url, path)
-    return FULLPATH_SCHEMA(path)
+        # In case the remote file is not modified, the download_content function will return the existing file,
+        # so update the modification time to now.
+        path.touch()
+    FONT_CACHE[value] = path
+    return value
 
 
 def download_web_font(value):
+    if value in FONT_CACHE:
+        return value
     url = value[CONF_URL]
-    path = get_font_path(value, TYPE_WEB)
+    path = _compute_local_font_path(value) / "font.ttf"
 
     external_files.download_content(url, path)
     _LOGGER.debug("download_web_font: path=%s", path)
-    return FULLPATH_SCHEMA(path)
+    FONT_CACHE[value] = path
+    return value
 
 
 EXTERNAL_FONT_SCHEMA = cv.Schema(
@@ -340,14 +403,14 @@ def validate_file_shorthand(value):
             }
         )
 
-    if value.endswith(".pcf") or value.endswith(".bdf"):
+    extension = Path(value).suffix
-        value = convert_bitmap_to_pillow_font(
+    if extension in BITMAP_EXTENSIONS:
-            CORE.relative_config_path(cv.file_(value))
+        return font_file_schema(
-        )
+            {
-        return {
                 CONF_TYPE: TYPE_LOCAL_BITMAP,
                 CONF_PATH: value,
             }
+        )
 
     return font_file_schema(
         {
@@ -391,7 +454,7 @@ FONT_SCHEMA = cv.Schema(
             cv.one_of(*glyphsets.defined_glyphsets())
         ),
         cv.Optional(CONF_IGNORE_MISSING_GLYPHS, default=False): cv.boolean,
-        cv.Optional(CONF_SIZE, default=20): cv.int_range(min=1),
+        cv.Optional(CONF_SIZE): cv.int_range(min=1),
         cv.Optional(CONF_BPP, default=1): cv.one_of(1, 2, 4, 8),
         cv.Optional(CONF_EXTRAS, default=[]): cv.ensure_list(
             cv.Schema(
@@ -406,114 +469,19 @@ FONT_SCHEMA = cv.Schema(
     },
 )
 
-CONFIG_SCHEMA = cv.All(FONT_SCHEMA, validate_glyphs)
+CONFIG_SCHEMA = cv.All(FONT_SCHEMA, validate_font_config)
-
-
-# PIL doesn't provide a consistent interface for both TrueType and bitmap
-# fonts. So, we use our own wrappers to give us the consistency that we need.
-
-
-class TrueTypeFontWrapper:
-    def __init__(self, font):
-        self.font = font
-
-    def getoffset(self, glyph):
-        _, (offset_x, offset_y) = self.font.font.getsize(glyph)
-        return offset_x, offset_y
-
-    def getmask(self, glyph, **kwargs):
-        return self.font.getmask(str(glyph), **kwargs)
-
-    def getmetrics(self, glyphs):
-        return self.font.getmetrics()
-
-
-class BitmapFontWrapper:
-    def __init__(self, font):
-        self.font = font
-        self.max_height = 0
-
-    def getoffset(self, glyph):
-        return 0, 0
-
-    def getmask(self, glyph, **kwargs):
-        return self.font.getmask(str(glyph), **kwargs)
-
-    def getmetrics(self, glyphs):
-        max_height = 0
-        for glyph in glyphs:
-            mask = self.getmask(glyph, mode="1")
-            _, height = mask.size
-            max_height = max(max_height, height)
-        return max_height, 0
 
 
 class EFont:
-    def __init__(self, file, size, codepoints):
+    def __init__(self, file, codepoints):
         self.codepoints = codepoints
-        path = file[CONF_PATH]
+        self.font: Face = FONT_CACHE[file]
-        self.name = Path(path).name
-        ftype = file[CONF_TYPE]
-        if ftype == TYPE_LOCAL_BITMAP:
-            self.font = load_bitmap_font(path)
-        else:
-            self.font = load_ttf_font(path, size)
-        self.ascent, self.descent = self.font.getmetrics(codepoints)
-
-
-def convert_bitmap_to_pillow_font(filepath):
-    from PIL import BdfFontFile, PcfFontFile
-
-    local_bitmap_font_file = external_files.compute_local_file_dir(
-        DOMAIN,
-    ) / os.path.basename(filepath)
-
-    copy_file_if_changed(filepath, local_bitmap_font_file)
-
-    local_pil_font_file = local_bitmap_font_file.with_suffix(".pil")
-    with open(local_bitmap_font_file, "rb") as fp:
-        try:
-            try:
-                p = PcfFontFile.PcfFontFile(fp)
-            except SyntaxError:
-                fp.seek(0)
-                p = BdfFontFile.BdfFontFile(fp)
-
-            # Convert to pillow-formatted fonts, which have a .pil and .pbm extension.
-            p.save(local_pil_font_file)
-        except (SyntaxError, OSError) as err:
-            raise core.EsphomeError(
-                f"Failed to parse as bitmap font: '{filepath}': {err}"
-            )
-
-    return str(local_pil_font_file)
-
-
-def load_bitmap_font(filepath):
-    from PIL import ImageFont
-
-    try:
-        font = ImageFont.load(str(filepath))
-    except Exception as e:
-        raise core.EsphomeError(f"Failed to load bitmap font file: {filepath}: {e}")
-
-    return BitmapFontWrapper(font)
-
-
-def load_ttf_font(path, size):
-    from PIL import ImageFont
-
-    try:
-        font = ImageFont.truetype(str(path), size)
-    except Exception as e:
-        raise core.EsphomeError(f"Could not load TrueType file {path}: {e}")
-
-    return TrueTypeFontWrapper(font)
 
 
 class GlyphInfo:
-    def __init__(self, data_len, offset_x, offset_y, width, height):
+    def __init__(self, data_len, advance, offset_x, offset_y, width, height):
         self.data_len = data_len
+        self.advance = advance
         self.offset_x = offset_x
         self.offset_y = offset_y
         self.width = width
@@ -537,15 +505,14 @@ async def to_code(config):
     }
     # get the codepoints from the glyphs key, flatten to a list of chrs and combine with the points from glyphsets
     point_set.update(flatten(config[CONF_GLYPHS]))
-    size = config[CONF_SIZE]
     # Create the codepoint to font file map
-    base_font = EFont(config[CONF_FILE], size, point_set)
+    base_font = FONT_CACHE[config[CONF_FILE]]
-    point_font_map: dict[str, EFont] = {c: base_font for c in point_set}
+    point_font_map: dict[str, Face] = {c: base_font for c in point_set}
     # process extras, updating the map and extending the codepoint list
     for extra in config[CONF_EXTRAS]:
         extra_points = flatten(extra[CONF_GLYPHS])
         point_set.update(extra_points)
-        extra_font = EFont(extra[CONF_FILE], size, extra_points)
+        extra_font = FONT_CACHE[extra[CONF_FILE]]
         point_font_map.update({c: extra_font for c in extra_points})
 
     codepoints = list(point_set)
@@ -553,28 +520,52 @@ async def to_code(config):
     glyph_args = {}
     data = []
     bpp = config[CONF_BPP]
-    if bpp == 1:
+    mode = ft_pixel_mode_grays
-        mode = "1"
-        scale = 1
-    else:
-        mode = "L"
     scale = 256 // (1 << bpp)
     # create the data array for all glyphs
     for codepoint in codepoints:
         font = point_font_map[codepoint]
-        mask = font.font.getmask(codepoint, mode=mode)
+        if not font.has_fixed_sizes:
-        offset_x, offset_y = font.font.getoffset(codepoint)
+            font.set_pixel_sizes(config[CONF_SIZE], 0)
-        width, height = mask.size
+        font.load_char(codepoint)
+        font.glyph.render(mode)
+        width = font.glyph.bitmap.width
+        height = font.glyph.bitmap.rows
+        buffer = font.glyph.bitmap.buffer
+        pitch = font.glyph.bitmap.pitch
         glyph_data = [0] * ((height * width * bpp + 7) // 8)
+        src_mode = font.glyph.bitmap.pixel_mode
         pos = 0
         for y in range(height):
             for x in range(width):
-                pixel = mask.getpixel((x, y)) // scale
+                if src_mode == ft_pixel_mode_mono:
+                    pixel = (
+                        (1 << bpp) - 1
+                        if buffer[y * pitch + x // 8] & (1 << (7 - x % 8))
+                        else 0
+                    )
+                else:
+                    pixel = buffer[y * pitch + x] // scale
                 for bit_num in range(bpp):
                     if pixel & (1 << (bpp - bit_num - 1)):
                         glyph_data[pos // 8] |= 0x80 >> (pos % 8)
                     pos += 1
-        glyph_args[codepoint] = GlyphInfo(len(data), offset_x, offset_y, width, height)
+        ascender = font.size.ascender // 64
+        if ascender == 0:
+            if font.has_fixed_sizes:
+                ascender = font.available_sizes[0].height
+            else:
+                _LOGGER.error(
+                    "Unable to determine ascender of font %s", config[CONF_FILE]
+                )
+        glyph_args[codepoint] = GlyphInfo(
+            len(data),
+            font.glyph.metrics.horiAdvance // 64,
+            font.glyph.bitmap_left,
+            ascender - font.glyph.bitmap_top,
+            width,
+            height,
+        )
         data += glyph_data
 
     rhs = [HexInt(x) for x in data]
@@ -598,6 +589,7 @@ async def to_code(config):
                         f"{str(prog_arr)} + {str(glyph_args[codepoint].data_len)}"
                     ),
                 ),
+                ("advance", glyph_args[codepoint].advance),
                 ("offset_x", glyph_args[codepoint].offset_x),
                 ("offset_y", glyph_args[codepoint].offset_y),
                 ("width", glyph_args[codepoint].width),
@@ -607,11 +599,19 @@ async def to_code(config):
 
     glyphs = cg.static_const_array(config[CONF_RAW_GLYPH_ID], glyph_initializer)
 
+    font_height = base_font.size.height // 64
+    ascender = base_font.size.ascender // 64
+    if font_height == 0:
+        if base_font.has_fixed_sizes:
+            font_height = base_font.available_sizes[0].height
+            ascender = font_height
+        else:
+            _LOGGER.error("Unable to determine height of font %s", config[CONF_FILE])
     cg.new_Pvariable(
         config[CONF_ID],
         glyphs,
         len(glyph_initializer),
-        base_font.ascent,
+        ascender,
-        base_font.ascent + base_font.descent,
+        font_height,
         bpp,
     )

esphome/components/font/font.cpp

@@ -81,7 +81,7 @@ void Font::measure(const char *str, int *width, int *x_offset, int *baseline, in
     if (glyph_n < 0) {
       // Unknown char, skip
       if (!this->get_glyphs().empty())
-        x += this->get_glyphs()[0].glyph_data_->width;
+        x += this->get_glyphs()[0].glyph_data_->advance;
       i++;
       continue;
     }
@@ -92,7 +92,7 @@ void Font::measure(const char *str, int *width, int *x_offset, int *baseline, in
     } else {
       min_x = std::min(min_x, x + glyph.glyph_data_->offset_x);
     }
-    x += glyph.glyph_data_->width + glyph.glyph_data_->offset_x;
+    x += glyph.glyph_data_->advance;
 
     i += match_length;
     has_char = true;
@@ -111,7 +111,7 @@ void Font::print(int x_start, int y_start, display::Display *display, Color colo
       // Unknown char, skip
       ESP_LOGW(TAG, "Encountered character without representation in font: '%c'", text[i]);
       if (!this->get_glyphs().empty()) {
-        uint8_t glyph_width = this->get_glyphs()[0].glyph_data_->width;
+        uint8_t glyph_width = this->get_glyphs()[0].glyph_data_->advance;
         display->filled_rectangle(x_at, y_start, glyph_width, this->height_, color);
         x_at += glyph_width;
       }
@@ -161,7 +161,7 @@ void Font::print(int x_start, int y_start, display::Display *display, Color colo
         }
       }
     }
-    x_at += glyph.glyph_data_->width + glyph.glyph_data_->offset_x;
+    x_at += glyph.glyph_data_->advance;
 
     i += match_length;
   }

esphome/components/font/font.h

@@ -15,6 +15,7 @@ class Font;
 struct GlyphData {
   const uint8_t *a_char;
   const uint8_t *data;
+  int advance;
   int offset_x;
   int offset_y;
   int width;

esphome/components/lvgl/font.cpp

@@ -19,7 +19,7 @@ static bool get_glyph_dsc_cb(const lv_font_t *font, lv_font_glyph_dsc_t *dsc, ui
   const auto *gd = fe->get_glyph_data(unicode_letter);
   if (gd == nullptr)
     return false;
-  dsc->adv_w = gd->offset_x + gd->width;
+  dsc->adv_w = gd->advance;
   dsc->ofs_x = gd->offset_x;
   dsc->ofs_y = fe->height - gd->height - gd->offset_y - fe->baseline;
   dsc->box_w = gd->width;