Metin2 game client (P0–P11) + mobile asset pipeline

Networked client on the existing Godot 4.7 + libgr2 renderer:
- net: m2dev wire protocol (libsodium KX + XChaCha20), auth/select/game
  phases, EntityStore world model, ~all GC/CG headers. char create/delete,
  private shop / mall / cube, SHOP_GC_START_EX, guild, party (+ CG_PARTY_SET_STATE),
  quests, dragon soul, refine, safebox, exchange.
- UI: in-game windows migrated 1:1 from the reference uiscript/root .py —
  char status (/stat), inventory+equipment, select-item ([SELECT_ITEM] quest
  token), system-option + game-option + ESC system menu, private-shop 39-grid,
  party info board, shop tabs, atlas, minimap, quickbar, chat, …
- EterGrnLib polish: GR2 material blend/two-sided, LOD crossfade, motion-event
  dispatch, contact shadow, ray-AABB picking, weapon grip pre-transform.

Portable asset IO (A1) — all extension/libgr2/formats/mtproto reads routed
through godot::FileAccess (res:// PCK works on iOS/Android); standalone-lib
*_path() kept for the non-Godot CTests. AssetResolver + PropertyRegistry
switched to a baked index (bake_asset_index.gd) instead of std::filesystem.

Mobile builds: build-{android,ios}.sh, export-android.sh, pack-assets.sh,
gen-debug-keystore.sh. Assets ship as a zip mounted at runtime by
project/asset_pack.gd (adb push now; HTTP download is a drop-in later).

ctest 10/10, 34 GDScript suites, macOS/iOS/Android all build.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013EJxkHiNKS4kybHS3XKyAJ

formats/terrain_files.cpp

@@ -0,0 +1,106 @@
+#include "terrain_files.h"
+
+#include "m2_tokvec.h" // read_file
+
+#include <cstring>
+
+namespace fmt {
+
+namespace {
+uint16_t rd_u16(const uint8_t* p) { return uint16_t(p[0]) | (uint16_t(p[1]) << 8); }
+} // namespace
+
+bool load_height_map(const std::string& path, HeightMap& out, std::string* err) {
+    std::string buf;
+    if (!read_file(path, buf)) { if (err) *err = "打不开 " + path; return false; }
+    const size_t need = size_t(HEIGHTMAP_RAW_XY) * HEIGHTMAP_RAW_XY * 2;
+    if (buf.size() != need) {
+        if (err) *err = "height.raw 大小 " + std::to_string(buf.size()) +
+                        " != " + std::to_string(need) + "（131*131*2）";
+        return false;
+    }
+    out.raw.resize(size_t(HEIGHTMAP_RAW_XY) * HEIGHTMAP_RAW_XY);
+    const auto* p = reinterpret_cast<const uint8_t*>(buf.data());
+    for (size_t i = 0; i < out.raw.size(); ++i) out.raw[i] = rd_u16(p + i * 2);
+    return true;
+}
+
+bool load_tile_map(const std::string& path, TileMap& out, std::string* err) {
+    std::string buf;
+    if (!read_file(path, buf)) { if (err) *err = "打不开 " + path; return false; }
+    const size_t need = size_t(TILEMAP_RAW_XY) * TILEMAP_RAW_XY;
+    if (buf.size() != need) {
+        if (err) *err = "tile.raw 大小 " + std::to_string(buf.size()) +
+                        " != " + std::to_string(need) + "（258*258）";
+        return false;
+    }
+    out.raw.assign(buf.begin(), buf.end());
+    return true;
+}
+
+bool load_attr_map(const std::string& path, AttrMap& out, std::string* err) {
+    std::string buf;
+    if (!read_file(path, buf)) { if (err) *err = "打不开 " + path; return false; }
+    const size_t payload = size_t(ATTRMAP_XY) * ATTRMAP_XY;
+    if (buf.size() != 6 + payload) {
+        if (err) *err = "attr.atr 大小 " + std::to_string(buf.size()) +
+                        " != " + std::to_string(6 + payload) + "（6B 头 + 256*256）";
+        return false;
+    }
+    const auto* p = reinterpret_cast<const uint8_t*>(buf.data());
+    uint16_t magic = rd_u16(p), w = rd_u16(p + 2), h = rd_u16(p + 4);
+    if (magic != ATTR_MAGIC) {
+        if (err) *err = "attr.atr magic " + std::to_string(magic) + " != 2634";
+        return false;
+    }
+    if (w != ATTRMAP_XY || h != ATTRMAP_XY) {
+        if (err) *err = "attr.atr 尺寸头 " + std::to_string(w) + "x" + std::to_string(h) +
+                        " != 256x256";
+        return false;
+    }
+    out.data.assign(buf.begin() + 6, buf.end());
+    return true;
+}
+
+bool load_water_map(const std::string& path, WaterMap& out, std::string* err) {
+    std::string buf;
+    if (!read_file(path, buf)) { if (err) *err = "打不开 " + path; return false; }
+    if (buf.size() < 7) { if (err) *err = "water.wtr 太小"; return false; }
+    const auto* p = reinterpret_cast<const uint8_t*>(buf.data());
+    uint16_t magic = rd_u16(p), w = rd_u16(p + 2), h = rd_u16(p + 4);
+    uint8_t layers = p[6];
+    if (magic != WATER_MAGIC) {
+        if (err) *err = "water.wtr magic " + std::to_string(magic) + " != 5426";
+        return false;
+    }
+    if (w != WATERMAP_XY || h != WATERMAP_XY) {
+        if (err) *err = "water.wtr 尺寸头 != 128x128";
+        return false;
+    }
+    const size_t ids = size_t(WATERMAP_XY) * WATERMAP_XY;
+    const size_t rest = buf.size() - 7;
+    // Terrain.cpp 接受两种：u16 层高 或 long(u32) 层高。
+    size_t hsize = 0;
+    if (rest == ids + size_t(layers) * 2) hsize = 2;
+    else if (rest == ids + size_t(layers) * 4) hsize = 4;
+    else if (rest == ids && layers == 0) hsize = 0;
+    else {
+        if (err) *err = "water.wtr 数据段大小 " + std::to_string(rest) +
+                        " 与 layers=" + std::to_string(layers) + " 不符";
+        return false;
+    }
+    out.layer_count = layers;
+    out.ids.assign(buf.begin() + 7, buf.begin() + 7 + ids);
+    out.heights.clear();
+    const auto* hp = p + 7 + ids;
+    for (int i = 0; i < layers; ++i) {
+        if (hsize == 2) out.heights.push_back((int16_t)rd_u16(hp + i * 2));
+        else if (hsize == 4)
+            out.heights.push_back((int32_t)(uint32_t(hp[i * 4]) | (uint32_t(hp[i * 4 + 1]) << 8) |
+                                            (uint32_t(hp[i * 4 + 2]) << 16) |
+                                            (uint32_t(hp[i * 4 + 3]) << 24)));
+    }
+    return true;
+}
+
+} // namespace fmt