Fix macOS FBX load failure from FreeType bundled-zlib symbol pollution

deps/Assimp/Assimp.cmake

@@ -6,6 +6,17 @@ else()
     set(_assimp_hash "SHA256=66dfbaee288f2bc43172440a55d0235dfc7bf885dda6435c038e8000e79582cb")
 endif()
 
+# Assimp's bundled zlib (contrib/zlib) is too old to compile against the modern
+# macOS SDK: its zutil.h takes the classic-Mac branch under TARGET_OS_MAC and
+# does `#define fdopen(fd,mode) NULL`, which then clobbers the SDK's real
+# `fdopen` prototype in <stdio.h> and breaks the build. On macOS use the system
+# zlib (already found by find_package(ZLIB) in deps-unix-common) instead.
+if(APPLE)
+    set(_assimp_build_zlib "-DASSIMP_BUILD_ZLIB=OFF")
+else()
+    set(_assimp_build_zlib "-DASSIMP_BUILD_ZLIB=ON")
+endif()
+
 bambustudio_add_cmake_project(Assimp
     URL ${_assimp_url}
     URL_HASH ${_assimp_hash}
@@ -19,7 +30,7 @@ bambustudio_add_cmake_project(Assimp
         -DASSIMP_BUILD_GLTF_IMPORTER=ON
         -DASSIMP_BUILD_OBJ_IMPORTER=ON
         -DASSIMP_BUILD_FBX_IMPORTER=ON
-        -DASSIMP_BUILD_ZLIB=ON
+        ${_assimp_build_zlib}
         -DASSIMP_WARNINGS_AS_ERRORS=OFF
         -DBUILD_WITH_STATIC_CRT=OFF
 )

deps/FREETYPE/FREETYPE.cmake

@@ -27,3 +27,24 @@ bambustudio_add_cmake_project(FREETYPE
 if(MSVC)
     add_debug_dep(dep_FREETYPE)
 endif()
+
+# On macOS the FT_DISABLE_ZLIB option above does NOT prevent FreeType from
+# linking the bundled zlib code into ftgzip.c.o - the inline copies of
+# inflate / inflateInit_ / zcalloc / adler32 etc. stay as global T symbols.
+# When BambuStudio is statically linked, those globals satisfy Assimp's
+# `inflateInit_` reference with FreeType's bundled 1.2.12 code while Assimp's
+# `inflate` still binds dynamically to the macOS system libz (1.2.11). The
+# resulting z_stream/state ABI mismatch makes Assimp's FBX 7.4 binary parser
+# fail with "CompressionFailure decompressing this file using gzip." on any
+# FBX that uses compressed property arrays. Strip the zlib externals after
+# install so only FT_Gzip_Uncompress / FT_Stream_OpenGzip remain visible.
+if(APPLE)
+    ExternalProject_Add_Step(dep_FREETYPE strip_zlib_globals
+        COMMENT "Stripping FreeType bundled-zlib globals from libfreetype.a (macOS)"
+        DEPENDEES install
+        ALWAYS 1
+        COMMAND ${CMAKE_COMMAND} -E env bash
+                "${CMAKE_CURRENT_LIST_DIR}/strip_libfreetype_zlib.sh"
+                "${DESTDIR}/usr/local/lib/libfreetype.a"
+    )
+endif()

deps/FREETYPE/strip_libfreetype_zlib.sh

@@ -0,0 +1,136 @@
+#!/usr/bin/env bash
+# Strip global zlib symbols out of FreeType's bundled gzip code on macOS.
+#
+# FreeType 2.12.1 always embeds its own copy of zlib inside ftgzip.c.o, even
+# when configured with FT_DISABLE_ZLIB=TRUE, because some other FreeType TUs
+# call FT_Gzip_Uncompress / FT_Stream_OpenGzip. Those zlib internals
+# (_inflate, _inflateInit_, _zcalloc, _adler32, ...) are exported as global T
+# symbols. When BambuStudio is statically linked, the linker resolves
+# Assimp's `inflateInit_` reference to FreeType's bundled 1.2.12 copy while
+# `inflate` still binds at runtime to the system libz.1.dylib (1.2.11). The
+# resulting z_stream/state ABI mismatch makes Assimp's FBX 7.4 binary parser
+# return CompressionFailure for any FBX that uses compressed property arrays
+# (the user-visible "无法解析文件格式" for chess_set_2k.fbx / Dragon.fbx).
+#
+# To keep FT_Gzip_* functional while preventing the symbol pollution, this
+# script rewrites ftgzip.c.o inside libfreetype.a so that all the zlib
+# helpers it inlines become private (lowercase t) while the public
+# FT_Gzip_Uncompress / FT_Stream_OpenGzip stay externally visible.
+#
+# The script is idempotent: re-running it on an already-patched archive is a
+# no-op.
+
+set -euo pipefail
+
+LIBFREETYPE_PATH="${1:?usage: $0 <path-to-libfreetype.a>}"
+
+if [[ ! -f "${LIBFREETYPE_PATH}" ]]; then
+    echo "[strip_libfreetype_zlib] libfreetype.a not found: ${LIBFREETYPE_PATH}" >&2
+    exit 1
+fi
+
+if [[ "$(uname -s)" != "Darwin" ]]; then
+    echo "[strip_libfreetype_zlib] skipped on non-macOS"
+    exit 0
+fi
+
+# Symbols that must remain external (anything else in ftgzip.c.o gets hidden).
+LOCALIZE_SYMBOLS=(
+    _crc32_combine
+    _crc32_combine64
+    _crc32_combine_gen
+    _crc32_combine_gen64
+    _crc32_combine_op
+    _crc32_z
+    _get_crc_table
+    _inflate
+    _inflateInit_
+    _inflateInit2_
+    _inflateEnd
+    _inflateReset
+    _inflateReset2
+    _inflateResetKeep
+    _inflateSetDictionary
+    _inflateSyncPoint
+    _inflateUndermine
+    _inflateValidate
+    _inflate_fast
+    _inflate_table
+    _zError
+    _zcalloc
+    _zcfree
+    _zlibCompileFlags
+    _zlibVersion
+    _zmemcmp
+    _zmemcpy
+    _zmemzero
+    _adler32
+    _adler32_combine
+    _adler32_combine64
+    _adler32_z
+)
+
+# Quick guard: if libfreetype.a no longer exports zlib globals, we're done.
+if ! nm "${LIBFREETYPE_PATH}" 2>/dev/null | grep -qE "^[0-9a-f]+ T _(inflate|inflateInit_|zcalloc|zlibVersion)$"; then
+    echo "[strip_libfreetype_zlib] libfreetype.a already clean: ${LIBFREETYPE_PATH}"
+    exit 0
+fi
+
+WORK_DIR="$(mktemp -d -t libfreetype_strip.XXXXXX)"
+trap 'rm -rf "${WORK_DIR}"' EXIT
+
+LOCALIZE_LIST="${WORK_DIR}/localize.list"
+printf '%s\n' "${LOCALIZE_SYMBOLS[@]}" > "${LOCALIZE_LIST}"
+
+ARCHES=$(lipo -archs "${LIBFREETYPE_PATH}" 2>/dev/null || echo "")
+if [[ -z "${ARCHES}" ]]; then
+    ARCHES="$(uname -m)"
+fi
+
+PATCHED_SLICES=()
+for ARCH in ${ARCHES}; do
+    SLICE_DIR="${WORK_DIR}/${ARCH}"
+    mkdir -p "${SLICE_DIR}"
+    SLICE_LIB="${SLICE_DIR}/libfreetype.a"
+    if [[ "${ARCHES}" == *" "* ]]; then
+        lipo "${LIBFREETYPE_PATH}" -thin "${ARCH}" -output "${SLICE_LIB}"
+    else
+        cp "${LIBFREETYPE_PATH}" "${SLICE_LIB}"
+    fi
+
+    pushd "${SLICE_DIR}" >/dev/null
+    ar -x libfreetype.a ftgzip.c.o
+    # macOS' ld -r needs an explicit platform_version, otherwise it complains
+    # about missing LC_BUILD_VERSION. We mirror the toolchain default
+    # (10.15 → SDK 13.1) used by BambuStudio's CMake setup.
+    xcrun ld -r ftgzip.c.o \
+        -unexported_symbols_list "${LOCALIZE_LIST}" \
+        -arch "${ARCH}" \
+        -platform_version macos 10.15 13.1 \
+        -o ftgzip.clean.c.o
+    mv ftgzip.clean.c.o ftgzip.c.o
+    ar -d libfreetype.a ftgzip.c.o
+    ar -q libfreetype.a ftgzip.c.o
+    ranlib libfreetype.a 2>/dev/null || true
+    popd >/dev/null
+
+    PATCHED_SLICES+=("${SLICE_LIB}")
+done
+
+if (( ${#PATCHED_SLICES[@]} == 1 )); then
+    cp "${PATCHED_SLICES[0]}" "${LIBFREETYPE_PATH}"
+else
+    lipo -create "${PATCHED_SLICES[@]}" -output "${LIBFREETYPE_PATH}"
+fi
+
+if nm "${LIBFREETYPE_PATH}" 2>/dev/null | grep -qE "^[0-9a-f]+ T _(inflate|inflateInit_|zcalloc|zlibVersion)$"; then
+    echo "[strip_libfreetype_zlib] FAILED to hide zlib externals in ${LIBFREETYPE_PATH}" >&2
+    exit 2
+fi
+
+if ! nm "${LIBFREETYPE_PATH}" 2>/dev/null | grep -qE "^[0-9a-f]+ T _FT_Gzip_Uncompress$"; then
+    echo "[strip_libfreetype_zlib] FAILED to preserve _FT_Gzip_Uncompress in ${LIBFREETYPE_PATH}" >&2
+    exit 3
+fi
+
+echo "[strip_libfreetype_zlib] patched ${LIBFREETYPE_PATH} (arches: ${ARCHES})"