Version 1.3.1:
 * fix some bugs.

Version 1.3:
 * add MOTION_ACCELERATE command for changing motion speed.
 * add a scroll bar to the debug display.
 * add gravity_factor and lipsync_priority in .mdf options.
 * modify MODEL_ADD command to switch cartoon rendering.
 * change the time unit in all options and commands from millisecond to second.
 * change option names from *_frame to *_time.
 * modify sample Makefiles for MinGW, Mac OS X, and Unix-like systems.
 * change rigid body colors according to their type in debug display.
 * keep rigid body status when they are turned off.
 * fix some bugs.
 * update libraries (GLFW 2.7.6, Julius 4.2.2, libpng 1.5.12, PortAudio v19_20111121, and zlib 1.2.7).

Version 1.2:
 * fix some bugs.
 * update libraries (Bullet Physics 2.79, GLFW 2.7.2, hts_engine API 1.06, Julius 4.2.1, libpng 1.5.7, and Open JTalk 1.05).

Version 1.1:
 * fix many bugs.
 * replace OS-dependent code with GLFW.
 * add sample Makefiles for MinGW, Mac OS X, and Unix-like systems.
 * add bone skeleton view by B key.
 * add VALUE_GET command and VALUE_EVENT_GET event.
 * improve timer precisition.
 * update libraries (Bullet Physics 2.78, hts_engine API 1.05, libpng 1.5.2, and Open JTalk 1.04).
 * remove some OS-dependent functions.

Version 1.0:
 * the stable release.
 * support camera motion file.
 * add motion holding by H key.
 * modify CAMERA command parameter.
 * update libraries (Julius 4.2 and Open JTalk 1.03).
 * fix bugs.

Version RC2:
 * modify CAMERA, MOTION_ADD, and TIMER_START commands.
 * support multi-FST in voice interaction manager.
 * support motion priority.
 * support motion interpolation for slow motions.
 * support rendering by Z order for correct alpha blending.
 * remove many warnings for compiler.
 * add maximum number of models in .mdf options.
 * add model translation of X-Y position by SHIFT+CTRL+drag.
 * force edge drawing at model selection.
 * modify buffer length.
 * fix many bugs.

Version RC:
 * show log of speech recognition and voice interaction manager.
 * support user's dictionary for speech recognition.
 * support JPEG files.
 * support mp3 file drop.
 * add VALUE command and event.
 * add KEY_POST, EXECUTE, and CAMERA command.
 * fix many bugs.

Version Beta:
 * support lipsync definition per model.
 * redesign the parameter set which can be defined in the MDF file.
 * show motion aliases in the debug mode.
 * add TIMER command and event.
 * add PLUGIN command and event.
 * add Drag and Drop events.
 * fix many bugs.

Version Alpha:
 * the first release.
