feat(core): add arg to gen_font.py to gen C data

- usage with `--gen-c`
- default is now Rust

[no changelog]

core/tools/build_templates

@@ -4,8 +4,10 @@ set -e
 CWD=`dirname "$0"`
 RENDER="$CWD/../vendor/trezor-common/tools/cointool.py render -M T1B1"
 
-# Search both in `core/src` and `core/embed` - Solana templates are excluded since those are handled separately
-FIND_TEMPLATES="find $CWD/.. -name *.mako -not -name _proto* -not -path *solana*"
+# Search both in `core/src` and `core/embed`
+# - Solana templates are excluded since those are handled separately
+# - `gen_font.mako` is excluded as it's used from `gen_font.py`
+FIND_TEMPLATES="find $CWD/.. -name *.mako -not -name _proto* -not -path *solana* -not -name gen_font.mako"
 
 check_results() {
     CHECK_FAIL=0

core/tools/codegen/gen_font.mako

@@ -0,0 +1,59 @@
+//! This file is generated by core/tools/codegen/gen_font.py
+#![cfg_attr(any(), rustfmt::skip)]
+#![allow(non_upper_case_globals)]
+// Each glyph:
+//   - first two bytes: width, height
+//   - next three bytes: advance, bearingX, bearingY
+//   - rest is packed ${bpp}-bit glyph data
+
+use crate::ui::display::font::FontInfo;
+
+% for g in glyphs:
+/// '${g["char"]}' (ASCII ${g["ascii"]})
+const ${g["var_name"]}: [u8; ${g["arr_len"]}] = [ ${g["arr_content"]} ];
+
+% endfor
+/// Nonprintable glyph (inverse colors of '?')
+const ${nonprintable["var_name"]}: [u8; ${nonprintable["arr_len"]}] = [ ${nonprintable["arr_content"]} ];
+% if gen_normal:
+
+/// Array of references for '${name}' normal ASCII glyphs
+const Font_${name}: [&[u8]; ${len(glyph_array)}] = [
+% for ref in glyph_array:
+    ${ref},
+% endfor
+];
+% endif
+% if gen_upper:
+
+/// Array of references for '${name}' ASCII glyphs (forced uppercase)
+const Font_${name}_upper: [&[u8]; ${len(glyph_array_upper)}] = [
+% for ref in glyph_array_upper:
+    ${ref},
+% endfor
+];
+% endif
+% if gen_normal:
+
+/// FontInfo struct for normal ASCII usage
+pub const Font_${name}_info: FontInfo = FontInfo {
+    translation_blob_idx: ${font_info["translation_blob_idx"]},
+    height: ${font_info["height"]},
+    max_height: ${font_info["max_height"]},
+    baseline: ${font_info["baseline"]},
+    glyph_data: &${font_info["glyph_array"]},
+    glyph_nonprintable: &${font_info["nonprintable"]},
+};
+% endif
+% if gen_upper:
+
+/// FontInfo struct for forced uppercase usage
+pub const Font_${name}_upper_info: FontInfo = FontInfo {
+    translation_blob_idx: ${font_info_upper["translation_blob_idx"]},
+    height: ${font_info_upper["height"]},
+    max_height: ${font_info_upper["max_height"]},
+    baseline: ${font_info_upper["baseline"]},
+    glyph_data: &${font_info_upper["glyph_array"]},
+    glyph_nonprintable: &${font_info_upper["nonprintable"]},
+};
+% endif

core/tools/codegen/gen_font.py

@@ -1,6 +1,8 @@
 #!/usr/bin/env python3
 
-# script used to generate core/embed/gfx/fonts/font_*_*.c
+# script used to generate
+#  1) core/embed/gfx/fonts/font_*_*.c for `prodtest` and `bootloader_ci`
+#  2) rust/src/ui/layout_*/fonts/font_*_*.rs for `bootloader` and `firmware`
 
 from __future__ import annotations
 
@@ -13,6 +15,7 @@
 
 # pip install freetype-py
 import freetype
+from mako.template import Template
 
 from foreign_chars import all_languages
 
@@ -24,9 +27,12 @@ def _normalize(s: str) -> str:
 HERE = Path(__file__).parent
 CORE_ROOT = HERE.parent.parent
 FONTS_DIR = HERE / "fonts"
+RUST_MAKO_TMPL = HERE / "gen_font.mako"
 OUT_DIR = HERE / ".." / ".." / "embed" / "gfx" / "fonts"
 C_FONTS_DEST = CORE_ROOT / "embed" / "gfx" / "fonts"
 JSON_FONTS_DEST = CORE_ROOT / "translations" / "fonts"
+RUST_FONTS_DEST = CORE_ROOT / "embed" / "rust" / "src" / "ui"
+LAYOUT_NAME = ""
 
 MIN_GLYPH = ord(" ")
 MAX_GLYPH = ord("~")
@@ -182,6 +188,7 @@ def from_face(
             print(f"normalizing bearingY {bearingY} for '{c}'")
             bearingY = 0
         assert bearingY >= 0 and bearingY <= 255
+
         buf = list(bitmap.buffer)
         # discard non-space pixels on the left side
         if remove_left > 0 and width > 0:
@@ -275,6 +282,7 @@ def __init__(
         self.ext = ext
         self.gen_normal = gen_normal
         self.gen_upper = gen_upper
+
         self.face = freetype.Face(str(FONTS_DIR / f"{name}-{style}.{ext}"))
         self.face.set_pixel_sizes(0, size)  # type: ignore
         self.fontname = f"{name.lower()}_{style.lower()}_{size}"
@@ -293,14 +301,27 @@ def _c_file_name(self) -> Path:
     def _h_file_name(self) -> Path:
         return C_FONTS_DEST / f"font_{self.fontname}.h"
 
-    def write_files(self) -> None:
-        self.write_c_files()
+    @property
+    def _rs_file_name(self) -> Path:
+        return (
+            RUST_FONTS_DEST
+            / f"layout_{LAYOUT_NAME}"
+            / "fonts"
+            / f"font_{self.fontname}.rs"
+        )
+
+    def write_files(self, gen_c: bool = False) -> None:
+        # C files:
+        if gen_c:
+            self.write_c_files()
+        # JSON files:
         if self.gen_normal:
             self.write_foreign_json(upper_cased=False)
         if self.gen_upper:
             self.write_foreign_json(upper_cased=True)
         if WRITE_WIDTHS:
             self.write_char_widths_files()
+        self.write_rust_file()
 
     def write_c_files(self) -> None:
         self._write_c_file()
@@ -468,19 +489,138 @@ def _write_h_file(self) -> None:
                     f"extern const font_info_t Font_{self._name_style_size}_upper_info;\n"
                 )
 
+    # --------------------------------------------------------------------
+    # Rust code generation
+    # --------------------------------------------------------------------
+    def write_rust_file(self) -> None:
+        """
+        Write a Rust source file using a Mako template.
+        """
+        # Build a dict with all data needed by the template.
+        # 1) Gather ASCII glyph definitions.
+        glyphs = []
+        for i in range(MIN_GLYPH, MAX_GLYPH + 1):
+            c = chr(i)
+            if c.islower() and not self.gen_normal:
+                continue
+            self._load_char(c)
+            glyph = Glyph.from_face(self.face, c, self.shaveX)
+            arr_bytes = glyph.to_bytes(self.bpp)
+            glyphs.append(
+                {
+                    "ascii": i,
+                    "char": glyph.char,
+                    "var_name": f"Font_{self._name_style_size}_glyph_{i}",
+                    "arr_len": len(arr_bytes),
+                    "arr_content": ", ".join(str(n) for n in arr_bytes),
+                }
+            )
 
-def gen_layout_bolt():
-    FaceProcessor("Roboto", "Regular", 20).write_files()
-    FaceProcessor("Roboto", "Bold", 20).write_files()
-    FaceProcessor("TTHoves", "Regular", 21, ext="otf").write_files()
-    FaceProcessor("TTHoves", "DemiBold", 21, ext="otf").write_files()
+        # 2) Nonprintable glyph.
+        self._load_char("?")
+        glyph_np = Glyph.from_face(self.face, "?", self.shaveX, inverse_colors=True)
+        arr_bytes_np = glyph_np.to_bytes(self.bpp)
+        nonprintable = {
+            "var_name": f"Font_{self._name_style_size}_glyph_nonprintable",
+            "arr_len": len(arr_bytes_np),
+            "arr_content": ", ".join(str(n) for n in arr_bytes_np),
+        }
+
+        # 3) Build arrays of glyph references.
+        glyph_array = []
+        glyph_array_upper = []
+        if self.gen_normal:
+            glyph_array = [
+                f"&Font_{self._name_style_size}_glyph_{i}"
+                for i in range(MIN_GLYPH, MAX_GLYPH + 1)
+            ]
+        if self.gen_upper:
+            for i in range(MIN_GLYPH, MAX_GLYPH + 1):
+                if chr(i).islower():
+                    c_to = chr(i).upper()
+                    i_mapped = ord(c_to)
+                    glyph_array_upper.append(
+                        f"&Font_{self._name_style_size}_glyph_{i_mapped}, // {chr(i)} -> {c_to}"
+                    )
+                else:
+                    glyph_array_upper.append(f"&Font_{self._name_style_size}_glyph_{i}")
+
+        # 4) Recompute font_ymin and font_ymax.
+        self.font_ymin = 0
+        self.font_ymax = 0
+        for i in range(MIN_GLYPH, MAX_GLYPH + 1):
+            c = chr(i)
+            if c.islower() and not self.gen_normal:
+                continue
+            self._load_char(c)
+            glyph = Glyph.from_face(self.face, c, self.shaveX)
+            yMin = glyph.bearingY - glyph.rows
+            yMax = yMin + glyph.rows
+            self.font_ymin = min(self.font_ymin, yMin)
+            self.font_ymax = max(self.font_ymax, yMax)
+
+        # 5) Build FontInfo definitions.
+        font_info = None
+        font_info_upper = None
+        if self.gen_normal:
+            font_info = {
+                "variant": "normal",
+                "height": self.size,
+                "max_height": self.font_ymax - self.font_ymin,
+                "baseline": -self.font_ymin,
+                "glyph_array": f"Font_{self._name_style_size}",
+                "nonprintable": f"Font_{self._name_style_size}_glyph_nonprintable",
+            }
+        if self.gen_upper:
+            font_info_upper = {
+                "variant": "upper",
+                "height": self.size,
+                "max_height": self.font_ymax - self.font_ymin,
+                "baseline": -self.font_ymin,
+                "glyph_array": f"Font_{self._name_style_size}_upper",
+                "nonprintable": f"Font_{self._name_style_size}_glyph_nonprintable",
+            }
+
+        data = {
+            "bpp": self.bpp,
+            "name": self._name_style_size,
+            "glyphs": glyphs,
+            "nonprintable": nonprintable,
+            "glyph_array": glyph_array,
+            "glyph_array_upper": glyph_array_upper,
+            "gen_normal": self.gen_normal,
+            "gen_upper": self.gen_upper,
+            "font_info": font_info,
+            "font_info_upper": font_info_upper,
+        }
+
+        # Load the Mako template from the same directory.
+        with open(RUST_MAKO_TMPL, "r") as f:
+            template_content = f.read()
+        template = Template(template_content)
+        rendered = template.render(**data)
+
+        # Write the rendered template into the Rust file.
+        with open(self._rs_file_name, "wt") as f:
+            f.write(rendered)
+
+
+def gen_layout_bolt(gen_c: bool = False):
+    global LAYOUT_NAME
+    LAYOUT_NAME = "bolt"
+    FaceProcessor("Roboto", "Regular", 20).write_files(gen_c)
+    FaceProcessor("Roboto", "Bold", 20).write_files(gen_c)
+    FaceProcessor("TTHoves", "Regular", 21, ext="otf").write_files(gen_c)
+    FaceProcessor("TTHoves", "DemiBold", 21, ext="otf").write_files(gen_c)
     FaceProcessor(
         "TTHoves", "Bold", 17, ext="otf", gen_normal=False, gen_upper=True
-    ).write_files()
-    FaceProcessor("RobotoMono", "Medium", 20).write_files()
+    ).write_files(gen_c)
+    FaceProcessor("RobotoMono", "Medium", 20).write_files(gen_c)
 
 
-def gen_layout_caesar():
+def gen_layout_caesar(gen_c: bool = False):
+    global LAYOUT_NAME
+    LAYOUT_NAME = "caesar"
     FaceProcessor(
         "PixelOperator",
         "Regular",
@@ -489,7 +629,7 @@ def gen_layout_caesar():
         shaveX=1,
         gen_normal=True,
         gen_upper=True,
-    ).write_files()
+    ).write_files(gen_c)
     FaceProcessor(
         "PixelOperator",
         "Bold",
@@ -498,25 +638,31 @@ def gen_layout_caesar():
         shaveX=1,
         gen_normal=True,
         gen_upper=True,
-    ).write_files()
-    FaceProcessor("PixelOperatorMono", "Regular", 8, bpp=1, shaveX=1).write_files()
-    FaceProcessor("Unifont", "Regular", 16, bpp=1, shaveX=1, ext="otf").write_files()
+    ).write_files(gen_c)
+    FaceProcessor("PixelOperatorMono", "Regular", 8, bpp=1, shaveX=1).write_files(gen_c)
+    FaceProcessor("Unifont", "Regular", 16, bpp=1, shaveX=1, ext="otf").write_files(
+        gen_c
+    )
     # NOTE: Unifont Bold does not seem to have czech characters
-    FaceProcessor("Unifont", "Bold", 16, bpp=1, shaveX=1, ext="otf").write_files()
+    FaceProcessor("Unifont", "Bold", 16, bpp=1, shaveX=1, ext="otf").write_files(gen_c)
 
 
-def gen_layout_delizia():
-    FaceProcessor("TTSatoshi", "DemiBold", 42, ext="otf").write_files()
-    FaceProcessor("TTSatoshi", "DemiBold", 21, ext="otf").write_files()
-    FaceProcessor("TTSatoshi", "DemiBold", 18, ext="otf").write_files()
-    FaceProcessor("RobotoMono", "Medium", 21).write_files()
+def gen_layout_delizia(gen_c: bool = False):
+    global LAYOUT_NAME
+    LAYOUT_NAME = "delizia"
+    FaceProcessor("TTSatoshi", "DemiBold", 42, ext="otf").write_files(gen_c)
+    FaceProcessor("TTSatoshi", "DemiBold", 21, ext="otf").write_files(gen_c)
+    FaceProcessor("TTSatoshi", "DemiBold", 18, ext="otf").write_files(gen_c)
+    FaceProcessor("RobotoMono", "Medium", 21).write_files(gen_c)
+
 
 LAYOUTS = {
     "bolt": gen_layout_bolt,
     "caesar": gen_layout_caesar,
     "delizia": gen_layout_delizia,
 }
 
+
 @click.command()
 @click.option(
     "--layout",
@@ -531,19 +677,25 @@ def gen_layout_delizia():
     default=False,
     help="Generate character width files",
 )
-def main(layout: str | None, write_widths: bool):
+@click.option(
+    "--gen-c",
+    is_flag=True,
+    default=False,
+    help="Also generate C font files",
+)
+def main(layout: str | None, write_widths: bool, gen_c: bool):
     """Generate font files for Trezor firmware."""
     global WRITE_WIDTHS
     WRITE_WIDTHS = write_widths
 
     if layout:
         click.echo(f"Generating fonts for layout: {layout}")
-        LAYOUTS[layout]()
+        LAYOUTS[layout](gen_c)
     else:
         click.echo("Generating all fonts")
         for layout_name, layout_func in LAYOUTS.items():
             click.echo(f"\nGenerating {layout_name} layout:")
-            layout_func()
+            layout_func(gen_c)
 
 
 if __name__ == "__main__":