# TK_User_Data

## Functions

| `TK_User_Data`
| `~TK_User_Data`
`TK_Status` | `Read`
`TK_Status` | `Write`
`TK_Status` | `Clone`
`TK_Status` | `ReadAscii`
`TK_Status` | `WriteAscii`
`TK_Status` | `Execute`
void | `Reset`
void | `SetUserData`
unsigned char const * | `GetUserData`
unsigned char * | `GetUserData`
int | `GetSize`
void | `Resize`
void | `SetSize`

## Detailed Description

class TK_User_Data : public BBaseOpcodeHandler

  Handles the TKE_Start_User_Data opcode.

  The HOOPS Stream File can contain user-data, which is denoted by TKE_Start_User_Data. TK_User_Data will handle the TKE_Start_User_Data opcode by simply reading the data, and not doing anything with it. Therefore, this class must be overloaded in order to both import (and handle), as well as export user-data.

  To ensure that user data will be gracefully handled (skipped-over) by non-custom handlers (meaning, an application that is using the default toolkit and doesn’t understand the custom user data), custom user data must be written out by exporting the following elements in order:

      1.  the TKE_Start_User_Data opcode
      2.  the number of bytes of user data that will follow
      3.  the user data itself
      4.  the TKE_Stop_User_Data_Opcode

  See the HOOPS/Stream Programming Guide for more detailed information about how to handle user data and create custom files.

  Public Functions

  inline TK_User_Data()

    constructor

  ~TK_User_Data()
  virtual TK_Status Read(BStreamFileToolkit &tk)

    Reads data from the toolkit buffer, decodes/decompresses it, and maps it to the opcode handlers data members. User-defined classes which need to write out custom data should utilize one of the available GetData() methods.

    Parameters

      tk – A reference to the BStreamFileToolkit object.

    Returns

      The result of the function call.

  virtual TK_Status Write(BStreamFileToolkit &tk)

    Encodes/compresses data and writes data to the toolkit buffer. User-defined classes which need to write out custom data should utilize one of the available PutData() methods, and first write out the opcode associated with the group of binary data followed by the data itself.

    Parameters

      tk – A reference to the BStreamFileToolkit object.

    Returns

      The result of the function call.

  virtual TK_Status Clone(BStreamFileToolkit &tk, BBaseOpcodeHandler **handler) const

    Copies the opcode handler

    Parameters

      - tk – A reference to the BStreamFileToolkit object.

      - handler – A pointer to the opcode handler object. Passed by reference.

    Returns

      The result of the function call.

  TK_Status ReadAscii(BStreamFileToolkit &tk)

    Deprecated.

  TK_Status WriteAscii(BStreamFileToolkit &tk)

    Deprecated.

  virtual TK_Status Execute(BStreamFileToolkit &tk)

    Processes the binary data that has been read for the current object, which involves passing the data to application-specific data structures.

    Parameters

      tk – A reference to the BStreamFileToolkit object.

    Returns

      The result of the function call.

  virtual void Reset()

    Resets the current opcode handler. This is called by the toolkit when it is done processing an opcode. This method reinitializes any opcode handler variables and frees up temporary data.

  inline void SetUserData(int size, unsigned char const *bytes = 0)

    Sets the data buffer. Allocates a buffer which can hold ‘size’ bytes and, if specified, copies ‘bytes’ into the buffer

  inline unsigned char const *GetUserData() const

    Returns the address of the data buffer

  inline unsigned char *GetUserData()

    Returns the address of the data buffer, which may be modified directly

  inline int GetSize() const

    Returns the size of the data buffer

  void Resize(int size)

    Change the size of the data buffer

  void SetSize(int size)

    Sets the size of the data buffer.