Add Chinese text rendering support

Extend the bitmap font pipeline with the Chinese Joker glyph subset and encode supported UTF-8 text for Tonc TTE. Move the affine map clear of the expanded font, add a compile-time VRAM overlap guard, and cover every custom glyph with host tests.

scripts/generate_chinese_joker_font.py

@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+
+"""Append the Chinese Joker-description glyph subset to the project's 8x8 ASCII font."""
+
+from argparse import ArgumentParser
+from pathlib import Path
+import re
+
+from PIL import Image, ImageDraw, ImageFont
+
+ASCII_FONT_HEIGHT = 48
+CELL_SIZE = 8
+GLYPHS_PER_ROW = 16
+
+
+def read_codepoints(table_path: Path) -> list[int]:
+    table = table_path.read_text(encoding="utf-8")
+    return [int(value, 16) for value in re.findall(r"CHINESE_GLYPH\(0x([0-9A-Fa-f]+)\)", table)]
+
+
+def main() -> None:
+    parser = ArgumentParser()
+    parser.add_argument("--font", required=True, help="Fusion Pixel Font 8px zh_hans TTF")
+    parser.add_argument("--table", default="include/def_chinese_glyph_table.h")
+    parser.add_argument("--image", default="font/gbalatro_sys8.png")
+    args = parser.parse_args()
+
+    image_path = Path(args.image)
+    base = Image.open(image_path).convert("RGB").crop((0, 0, 128, ASCII_FONT_HEIGHT))
+    codepoints = read_codepoints(Path(args.table))
+    extra_rows = (len(codepoints) + GLYPHS_PER_ROW - 1) // GLYPHS_PER_ROW
+
+    output = Image.new("RGB", (128, ASCII_FONT_HEIGHT + extra_rows * CELL_SIZE), "white")
+    output.paste(base, (0, 0))
+
+    draw = ImageDraw.Draw(output)
+    font = ImageFont.truetype(args.font, CELL_SIZE)
+    for index, codepoint in enumerate(codepoints):
+        x = (index % GLYPHS_PER_ROW) * CELL_SIZE
+        y = ASCII_FONT_HEIGHT + (index // GLYPHS_PER_ROW) * CELL_SIZE
+        draw.text((x, y - 1), chr(codepoint), font=font, fill="black")
+
+    output.save(image_path, optimize=True)
+    print(f"Appended {len(codepoints)} Chinese glyphs to {image_path}")
+
+
+if __name__ == "__main__":
+    main()

scripts/generate_font.py

@@ -5,7 +5,6 @@ import argparse
 
 CHAR_WIDTH = 8
 CHAR_HEIGHT = 8
-NUM_VERT_CHARS = 6
 NUM_HORZ_CHARS = 16
 WORD_SIZE = 32
 
@@ -48,8 +47,14 @@ img = img.convert("P")
 img = img.convert('1')
 img = ImageOps.invert(img)
 
+if img.width != NUM_HORZ_CHARS * CHAR_WIDTH or img.height % CHAR_HEIGHT != 0:
+    raise ValueError("font image must be 128px wide and a multiple of 8px high")
+
+num_vert_chars = img.height // CHAR_HEIGHT
+num_chars = num_vert_chars * NUM_HORZ_CHARS
+
 glyphs = []
-for char_y in range(NUM_VERT_CHARS):
+for char_y in range(num_vert_chars):
     for char_x in range(NUM_HORZ_CHARS):
         # Get the 8x8 crop area at our current character in the image
         pix_x = char_x * CHAR_WIDTH
@@ -86,7 +91,7 @@ with open(out_path, "w") as out:
     .global	gbalatro_sys8Font
 gbalatro_sys8Font:
     .word	gbalatro_sys8Glyphs, 0, 0
-    .hword	32, 96
+    .hword	32, %d
     .byte	8, 8
     .byte	8, 8
     .hword	8
@@ -94,9 +99,9 @@ gbalatro_sys8Font:
 
     .section .rodata
     .align	2
-    .global gbalatro_sys8Glyphs		@ 768 bytes (192 unsigned ints)
+    .global gbalatro_sys8Glyphs
 gbalatro_sys8Glyphs:
-""")
+""" % num_chars)
     
     for i, glyph in enumerate(glyphs):
         if first: