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

extension/src/static_object.cpp

@@ -0,0 +1,155 @@
+#include "static_object.h"
+
+#include "asset_io.h"
+#include "dxt.h"
+#include "gr2_bridge.h"
+#include "texture_util.h"
+
+#include <godot_cpp/classes/image.hpp>
+#include <godot_cpp/classes/image_texture.hpp>
+#include <godot_cpp/classes/standard_material3d.hpp>
+#include <godot_cpp/variant/packed_byte_array.hpp>
+#include <godot_cpp/variant/utility_functions.hpp>
+
+#include <asset_resolver.h>
+#include <gr2/gr2.h>
+
+#include <unordered_map>
+
+using namespace godot;
+
+namespace mtgodot {
+
+namespace {
+
+std::unordered_map<std::string, Ref<ImageTexture>> g_dds_cache;
+
+// Building albedo (sRGB colour) -> mobile-ASTC-eligible via make_color_texture
+// (no-op on desktop). mipmaps=false keeps the desktop result byte-identical to
+// the old path (buildings had no mip chain). §F4.
+Ref<ImageTexture> decode_dds_cached(const std::string &real_path) {
+	auto &cache = g_dds_cache;
+	auto it = cache.find(real_path);
+	if (it != cache.end())
+		return it->second;
+	Ref<ImageTexture> tex;
+	mtgodot::Image d = mtgodot::dds_from_file(godot::String(real_path.c_str()));
+	if (d.ok()) {
+		tex = mtgodot::make_color_texture(d.w, d.h, d.rgba.data(), d.rgba.size(),
+				/*mipmaps=*/false);
+	}
+	cache.emplace(real_path, tex);
+	return tex;
+}
+
+Ref<StandardMaterial3D> material_for(const std::string &tex_name, bool alpha_blend, bool two_sided,
+		const fmt::AssetResolver &res) {
+	Ref<StandardMaterial3D> mat;
+	mat.instantiate();
+	mat->set_albedo(Color(0.7f, 0.7f, 0.7f));
+	mat->set_roughness(1.0f);
+	mat->set_texture_filter(StandardMaterial3D::TEXTURE_FILTER_LINEAR_WITH_MIPMAPS_ANISOTROPIC);
+	mat->set_cull_mode(StandardMaterial3D::CULL_BACK);
+
+	String t = String(tex_name.c_str()).to_lower();
+	bool kw_alpha = t.find("leaf") != -1 || t.find("grass") != -1 || t.find("fence") != -1 ||
+			t.find("net") != -1 || t.find("ivy") != -1 || t.find("tree") != -1 ||
+			t.find("branch") != -1;
+	if (alpha_blend) {
+		// EterGrnLib TYPE_BLEND_PNT：真 alpha 混合（第 2 map 作 opacity）
+		mat->set_transparency(StandardMaterial3D::TRANSPARENCY_ALPHA);
+		mat->set_cull_mode(StandardMaterial3D::CULL_DISABLED);
+	} else if (kw_alpha) {
+		mat->set_transparency(StandardMaterial3D::TRANSPARENCY_ALPHA_SCISSOR);
+		mat->set_alpha_scissor_threshold(0.5f);
+		mat->set_cull_mode(StandardMaterial3D::CULL_DISABLED);
+	}
+	if (two_sided)
+		mat->set_cull_mode(StandardMaterial3D::CULL_DISABLED);
+
+	if (tex_name.empty())
+		return mat;
+	std::string rp = res.resolve(tex_name, nullptr);
+	if (rp.empty()) {
+		// gr2 里常是 .dds；有时资产用别的大小写 / 扩展。先只试原名。
+		return mat;
+	}
+	Ref<ImageTexture> tex = decode_dds_cached(rp);
+	if (tex.is_valid()) {
+		mat->set_texture(StandardMaterial3D::TEXTURE_ALBEDO, tex);
+		mat->set_albedo(Color(1, 1, 1));
+	}
+	return mat;
+}
+
+} // namespace
+
+Ref<godot::ArrayMesh> get_static_mesh(const std::string &real_gr2_path,
+		const fmt::AssetResolver &res, StaticMeshCache &cache) {
+	auto it = cache.by_path.find(real_gr2_path);
+	if (it != cache.by_path.end())
+		return it->second;
+
+	Ref<godot::ArrayMesh> result; // invalid until success
+
+	gr2::LoadError err;
+	auto loaded = mtgodot::gr2_from_file(godot::String(real_gr2_path.c_str()), &err);
+	if (!loaded) {
+		++cache.failed;
+		UtilityFunctions::push_warning(String("[static] gr2 load failed: ") +
+				real_gr2_path.c_str() + " (" + err.message.c_str() + ")");
+		cache.by_path.emplace(real_gr2_path, result);
+		return result;
+	}
+	const gr2::FileInfo &fi = loaded->file_info();
+
+	// 贴图名 -> 渲染态（来自 libgr2 dump_materials 的名字/map 推断）
+	std::vector<gr2::MaterialInfo> mats = gr2::dump_materials(*loaded);
+	std::map<std::string, std::pair<bool, bool>> tex_state; // lower(tex) -> {alpha, two_sided}
+	for (const auto &m : mats) {
+		std::string k;
+		for (char c : m.diffuse_texture)
+			k += (char)std::tolower((unsigned char)c);
+		if (!k.empty())
+			tex_state[k] = {m.alpha_blend, m.two_sided};
+	}
+
+	std::vector<mtgodot::RenderPart> parts = mtgodot::build_parts(fi);
+	AABB bounds;
+	Ref<godot::ArrayMesh> mesh = mtgodot::build_mesh(fi, parts, /*flip_winding=*/false, bounds);
+	if (mesh.is_valid() && mesh->get_surface_count() > 0) {
+		for (int s = 0; s < mesh->get_surface_count() && s < (int)parts.size(); ++s) {
+			const mtgodot::RenderPart &rp = parts[s];
+			std::string tex;
+			if (rp.mesh >= 0 && rp.mesh < (int)fi.meshes.size()) {
+				const auto &mt = fi.meshes[rp.mesh].material_textures;
+				if (rp.mat_index >= 0 && rp.mat_index < (int)mt.size())
+					tex = mt[rp.mat_index];
+				else if (!mt.empty())
+					tex = mt[0];
+			}
+			bool alpha = false, two = false;
+			{
+				std::string k;
+				for (char c : tex)
+					k += (char)std::tolower((unsigned char)c);
+				auto f = tex_state.find(k);
+				if (f != tex_state.end()) {
+					alpha = f->second.first;
+					two = f->second.second;
+				}
+			}
+			mesh->surface_set_material(s, material_for(tex, alpha, two, res));
+		}
+		result = mesh;
+		++cache.loaded;
+	} else {
+		++cache.failed;
+	}
+	cache.by_path.emplace(real_gr2_path, result);
+	return result;
+}
+
+void cleanup_static_object_cache() { g_dds_cache.clear(); }
+
+} // namespace mtgodot