Fix for exporting fbx bigger than 2GB

code/Common/DefaultIOStream.cpp

@@ -52,6 +52,35 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 using namespace Assimp;
 
+namespace
+{
+    template<size_t sizeOfPointer>
+    size_t select_ftell(FILE* file)
+    {
+        return ::ftell(file);
+    }
+
+    template<size_t sizeOfPointer>
+    int select_fseek(FILE* file, int64_t offset, int origin)
+    {
+        return ::fseek(file, static_cast<long>(offset), origin);
+    }
+
+#if defined _WIN32 && (!defined __GNUC__ || __MSVCRT_VERSION__ >= 0x0601)
+    template<>
+    size_t select_ftell<8>(FILE* file)
+    {
+        return ::_ftelli64(file);
+    }
+
+    template<>
+    int select_fseek<8>(FILE* file, int64_t offset, int origin)
+    {
+        return ::_fseeki64(file, offset, origin);
+    }
+#endif
+}
+
 // ----------------------------------------------------------------------------------
 DefaultIOStream::~DefaultIOStream()
 {
@@ -93,7 +122,7 @@ aiReturn DefaultIOStream::Seek(size_t pOffset,
         aiOrigin_END == SEEK_END && aiOrigin_SET == SEEK_SET");
 
     // do the seek
-    return (0 == ::fseek(mFile, (long)pOffset,(int)pOrigin) ? AI_SUCCESS : AI_FAILURE);
+    return (0 == select_fseek<sizeof(void*)>(mFile, (int64_t)pOffset,(int)pOrigin) ? AI_SUCCESS : AI_FAILURE);
 }
 
 // ----------------------------------------------------------------------------------
@@ -102,7 +131,7 @@ size_t DefaultIOStream::Tell() const
     if (!mFile) {
         return 0;
     }
-    return ::ftell(mFile);
+    return select_ftell<sizeof(void*)>(mFile);
 }
 
 // ----------------------------------------------------------------------------------

code/FBX/FBXCommon.h

@@ -50,9 +50,10 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 namespace Assimp {
 namespace FBX
 {
-    const std::string NULL_RECORD = { // 13 null bytes
-        '\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0'
-    }; // who knows why
+    const std::string NULL_RECORD = { // 25 null bytes in 64-bit and 13 null bytes in 32-bit
+        '\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0',
+        '\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0','\0'
+    }; // who knows why, it looks like two integers 32/64 bit (compressed and uncompressed sizes?) + 1 byte (might be compression type?)
     const std::string SEPARATOR = {'\x00', '\x01'}; // for use inside strings
     const std::string MAGIC_NODE_TAG = "_$AssimpFbx$"; // from import
     const int64_t SECOND = 46186158000; // FBX's kTime unit

code/FBX/FBXExportNode.cpp

@@ -325,9 +325,9 @@ void FBX::Node::BeginBinary(Assimp::StreamWriterLE &s)
     this->start_pos = s.Tell();
 
     // placeholders for end pos and property section info
-    s.PutU4(0); // end pos
-    s.PutU4(0); // number of properties
-    s.PutU4(0); // total property section length
+    s.PutU8(0); // end pos
+    s.PutU8(0); // number of properties
+    s.PutU8(0); // total property section length
 
     // node name
     s.PutU1(uint8_t(name.size())); // length of node name
@@ -352,9 +352,9 @@ void FBX::Node::EndPropertiesBinary(
     size_t pos = s.Tell();
     ai_assert(pos > property_start);
     size_t property_section_size = pos - property_start;
-    s.Seek(start_pos + 4);
-    s.PutU4(uint32_t(num_properties));
-    s.PutU4(uint32_t(property_section_size));
+    s.Seek(start_pos + 8); // 8 bytes of uint64_t of end_pos
+    s.PutU8(num_properties);
+    s.PutU8(property_section_size);
     s.Seek(pos);
 }
 
@@ -375,7 +375,7 @@ void FBX::Node::EndBinary(
     // now go back and write initial pos
     this->end_pos = s.Tell();
     s.Seek(start_pos);
-    s.PutU4(uint32_t(end_pos));
+    s.PutU8(end_pos);
     s.Seek(end_pos);
 }
 

code/FBX/FBXExporter.cpp

@@ -81,8 +81,8 @@ using namespace Assimp::FBX;
 // some constants that we'll use for writing metadata
 namespace Assimp {
 namespace FBX {
-    const std::string EXPORT_VERSION_STR = "7.4.0";
-    const uint32_t EXPORT_VERSION_INT = 7400; // 7.4 == 2014/2015
+    const std::string EXPORT_VERSION_STR = "7.5.0";
+    const uint32_t EXPORT_VERSION_INT = 7500; // 7.5 == 2016+
     // FBX files have some hashed values that depend on the creation time field,
     // but for now we don't actually know how to generate these.
     // what we can do is set them to a known-working version.