Font rendering map + double-byte patch

Font object layout (size `0x191C`, embedded by value in a manager struct)

Two UI font objects live at manager + 0x3A8 and manager + 0x1CC4 (difference = 0x191C).

+0x00  texture pointer (D3D texture object)
+0x04  max width
+0x08  max height
+0x0C  SpaceWidth
+0x10  LineDistance
+0x14  CharDistance
+0x18  flag (1 = built)
+0x1C  256 glyph entries x 16 bytes  = 4 floats (u1,v1,u2,v2) normalized UV
+0x101C 256 metric entries x 8 bytes = { int advance, int height }
+0x181C 256 "defined" bytes

The table stride differs (16 vs 8 vs 1), which is why the tables cannot be enlarged in place and a side table is used for CJK.

Key code

VA	role
`0x4EBF90`	parse/load `Fonts.dat` (generic config reader)
`0x4E7DC0`	set font texture
`0x4E7E30`	`AddChar(code, x1,y1,x2,y2)` — normalizes rect → stores glyph float[4] + metric[2]
`0x4EC168`	`mov cl,[ebp]` — parser takes only the first byte of `Code`
`0x4E7FD0`	measure text; loop body `0x4E7FF0`; metric lookups `0x4E802C`, `0x4E8033`
`0x4EAC40`	draw text; loop head
`0x4EACB0`	`movzx ecx,al` — glyph lookup site in draw loop
`0x4EACDC`,`0x4EAE9A`	metric lookups in draw loop
`0x4E56A0`	`IsCharDefined(font, code)`

Texture is bound once per draw call ([font] + vtable +0xF4), so ASCII and CJK glyphs must share one texture atlas.

Patch design (implemented)

A new PE section .cjk holds two code caves and two big tables:

.cjk RVA 0x566000 (VA 0x966000), size 0x1C0000
  0x00     draw_cave
  0x0100   metrics_cave
  0x0200   cjk_glyph  : 65536 x 16 bytes (u1,v1,u2,v2 floats)
  0x100200 cjk_metric : 65536 x 8 bytes  (advance,height ints)

Hooks (5-byte jmp rel32):

0x4EACB0 -> draw_cave (was movzx ecx,al)
0x4E8026 -> metrics_cave (was mov ebp,[ecx+0x14])

Behaviour of each cave:

al < 0x80: execute the original instructions, jump back to the next instruction.
al >= 0x80: decode a 2-byte code (al<<8)|[ptr+1]; copy the glyph float[4] into font glyph slot 0xFF and the metric into slot 0xFF; set ecx = 0xFF, advance the string pointer by one extra byte; jump back into the engine's unchanged quad-building code.

Slot 0xFF glyph lives at font+0x100C, its metric at font+0x1814; these do not collide with the real tables.

Requirements / limits

The font texture must contain both ASCII and CJK glyphs (one texture per draw). Plan: replace the UI font Texture with a 2048x2048 atlas and re-point the ASCII Char rects.
Lead bytes >= 0x80 are reserved for DBCS. ASCII is untouched.
Confirmed end to end: a GB2312-coded menu string rendered the mapped glyph on screen.

Tools

tools/add_section.py — append an executable PE section.
tools/apply_cjk.py — assemble the caves (keystone), add .cjk, write hooks and tables.
tools/decode_dat.py — decode/encode the XOR .dat files.
tools/fontparse.py — parse Fonts.dat into blocks + glyph rects.
tools/xrefs.py, tools/disasm.py, tools/scan_disp.py — RE helpers.

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