General functions

• buffer_zlib_is_available

  This variable holds status (true\false) of whether the native extension was successfully loaded. The extension may not be loaded in a few cases:

  • Extension is not supported on the target platform.
  • Extension' file is amiss (e.g. the user did not unzip the game before running).

  As per GameMaker rules, all calls to unavailable extensions return 0 instead, so you may want to check this and notify the user prior to performing any operations.

• buffer_deflate(buffer, offset, size, compression_level, ?out_buffer)

  Compresses a section of given buffer (specified by buffer, offset, size).
  compression_level can be between 1 (fastest) and 9 (smallest).
  If out_buffer is specified, the result is written to the current position in it (buffer is resized if needed). Otherwise a new buffer is created to store the result.
  Returns modified/created buffer' ID; buffer' position will point to the end of compressed data in it. In case of error, returns -1 and sets buffer_zlib_status.

• buffer_inflate(buffer, offset, size, ?out_buffer)

  Decompresses a section of given buffer (specified by buffer, offset, size).
  If out_buffer is specified, the result is written to the current position in it (buffer is resized if needed). Otherwise a new buffer is created to store the result.
  Returns modified/created buffer' ID; buffer' position will point to the end of decompressed data in it. In case of error, returns -1 and sets buffer_zlib_status.

• buffer_chunk_size

  Determines the initial size of the buffers that extension creates to store results (if not given a buffer), as well as the size that a buffer is expanded by if the data does not fit.
  Smaller values are more memory-efficient while larger values reduce the amount of back-and-forth calls between the native extension and the game.
  Default value is 16384 (16KB).

• buffer_zlib_status

  Holds a status ID from the last call to the extension. Possible values are:

  • buffer_zlib_status_ok: Execution finished successfully.
  • buffer_zlib_status_stream_error: Compression/decompression error.
  • buffer_zlib_status_data_error: Incorrect format/corruption.
  • buffer_zlib_status_memory_error: Not enough memory to decompress.
  • buffer_zlib_status_buffer_error: Premature finish / partial data.