This file has been dedicated to the public domain, to the extent
possible under applicable law, via CC0. See
http://creativecommons.org/publicdomain/zero/1.0/ for more
information. This file is offered as-is, without any warranty.

========================================================================

1.4
------------------------------------------------------------------------

Specification additions:
+ sge.gfx.Sprite.swap_color

Specification misc changes:
* Replaced uses of IOError with uses of OSError.

Specification bugfixes:
- Universal joystick events not being listed in generated documentation


1.3
------------------------------------------------------------------------

Specification additions:
+ sge.dsp.Object.image_width
+ sge.dsp.Object.image_height
+ sge.dsp.Object.image_left
+ sge.dsp.Object.image_right
+ sge.dsp.Object.image_xcenter
+ sge.dsp.Object.image_top
+ sge.dsp.Object.image_bottom
+ sge.dsp.Object.image_ycenter
+ sge.snd.Sound.parent

Specification misc changes:
* sge.gfx.Sprite.from_tween now supports all blend modes.
* sge.gfx.Font.from_sprite now offers an alternative, more fine-tuned
  way to map characters to the sprite's frames.
* It is now possible to specify a fallback character for sprite fonts
  for use when the character is not available in the font.
* sge.snd.Sound.play now supports the "force" argument to control
  whether or not the sound should play anyway if the maximum number of
  instances is playing (overriding existing instances).


1.2
------------------------------------------------------------------------

Specification additions:
+ sge.dsp.Object.image_blend_mode

Specification misc changes:
* When a sprite is specified as transparent, the SGE no longer tries to
  check whether or not the actual image file has transparency and apply
  arbitrary colorkey transparency otherwise.  This system was just too
  prone to errors caused by tools like Trimage removing alpha channels,
  and caused a bug in the Pygame SGE that could not be fixed.


1.1
------------------------------------------------------------------------

Specification misc changes:
* Removed the docstring section discussing implementation details.
  Instead, these details should now be discussed in a README
  accompanying the implementation.


1.0
------------------------------------------------------------------------

Specification additions:
+ sge.s
+ sge.SCALE_METHODS
+ sge.dsp.Game.scale_method

Specification removals:
- sge.dsp.Game.scale_smooth

Specification misc changes:
* All drawing and projecting methods now support blend modes.


0.24
------------------------------------------------------------------------

Specification additions:
+ sge.gfx.TileGrid
+ sge.gfx.Sprite.get_pixel
+ sge.gfx.Sprite.get_pixels
+ sge.gfx.Sprite.scale
+ sge.gfx.Sprite.from_tween
+ sge.gfx.Sprite.resize_canvas
+ sge.gfx.Sprite.extend
+ sge.snd.stop_all

Specification removals:
- sge.snd.Sound.stop_all

Specification misc changes:
* sge.dsp.Game.scale is now defined to suggest what resolution to use in
  fullscreen mode.
* Mirroring, flipping, and rotation of sprites can now be done on a
  specific frame.
* sge.gfx.Sprite.transparent can now be set to a color, in which case it
  defines the colorkey to use.


0.23
------------------------------------------------------------------------

Specification additions:
+ sge.joystick.get_value
+ sge.input.JoystickEvent
+ sge.Game.event_joystick
+ sge.Game.event_paused_joystick
+ sge.Room.event_joystick
+ sge.Room.event_paused_joystick
+ sge.Object.event_joystick
+ sge.Object.event_paused_joystick

Specification misc changes:
* Moved sge.Color, sge.Sprite, sge.Font, sge.BackgroundLayer, and
  sge.Background to the new sge.gfx module.
* Changed the default text color in text drawing and projection methods
  to white.
* Moved sge.Game, sge.Room, sge.View, and sge.Object to the new sge.dsp
  module.
* Moved sge.Sound and sge.Music to the new sge.snd module.
* Rotation is now clockwise instead of counter-clockwise.
* Sound and music volumes are now from 0 to 1, not 0 to 100.


0.22
------------------------------------------------------------------------

Specification misc changes:
* Added a warning about certain methods' interaction with certain lists.
* Clarified how colorkeys are chosen in the documentation.

Specification bugfixes:
- "Hello world" tutorial being outdated


0.21
------------------------------------------------------------------------

Specification additions:
+ sge.Game.delta_max

Specification misc changes:
* Window projections now have Z-axis values.  These Z-axis values are
  independent of all others.
* sge.game.mouse.z is now used to determine the Z-axis value of the
  mouse projection.
* As a consequence of the Z-axis value introduction to window
  projections, it's possible to make window projections obscure the
  mouse cursor.


0.20
------------------------------------------------------------------------

Specification additions:
+ sge.Room.object_area_width
+ sge.Room.object_area_height
+ sge.Room.object_areas
+ sge.Room.object_area_void
+ sge.Room.get_objects_at

Specification removals:
- sge.Object.event_inactive_step
- sge.Object.event_inactive_key_press
- sge.Object.event_inactive_key_release
- sge.Object.event_inactive_mouse_move
- sge.Object.event_inactive_mouse_button_press
- sge.Object.event_inactive_mouse_button_release
- sge.Object.event_inactive_joystick_axis_move
- sge.Object.event_inactive_joystick_hat_move
- sge.Object.event_inactive_joystick_trackball_move
- sge.Object.event_inactive_joystick_button_press
- sge.Object.event_inactive_joystick_button_release

Specification misc changes:
* Objects with the same Z-axis value are now positioned based on
  creation time (like the Pygame SGE).

Specification bugfixes:
- Remaining references to "sge.StellarClass" in docstrings


0.19
------------------------------------------------------------------------

Specification misc changes:
* Negative frame rates now indicate reversed animation.
* Added "transition_arg" argument to sge.Room.start, for special
  transition variations.  Currently, this allows control over the
  position of iris in and iris out transitions, and the size of the
  rectangles in the matrix wipe transition.


0.18
------------------------------------------------------------------------

Specification misc changes:
* Improved the method of deceleration (the old one was quite buggy).
* The order of event_create calls is now defined to be the same as the
  order in which the objects were added to the room. (It was previously
  undefined.)

0.17
------------------------------------------------------------------------

Specification additions:
+ sge.Object.xacceleration
+ sge.Object.yacceleration
+ sge.Object.xdeceleration
+ sge.Object.ydeceleration
+ sge.Object.move_x
+ sge.Object.move_y

Specification removals:
- sge.Object.event_collision_left
- sge.Object.event_collision_right
- sge.Object.event_collision_top
- sge.Object.event_collision_bottom
- sge.Game.event_mouse_collision_left
- sge.Game.event_mouse_collision_right
- sge.Game.event_mouse_collision_top
- sge.Game.event_mouse_collision_bottom

Specification misc changes:
* sge.Object.event_collision now has arguments indicating direction, to
  replace the old directional collision events.
* Default implementation of sge.Object.event_update_position now includes
  handling of acceleration and deceleration, when applicable.


0.16
------------------------------------------------------------------------

Specification additions:
+ sge.Sprite.copy
+ sge.Sprite.from_text
+ sge.Sprite.mirror
+ sge.Sprite.flip
+ sge.Sprite.rotate

Specification removals:
- sge.ALIGN_LEFT
- sge.ALIGN_RIGHT
- sge.ALIGN_CENTER
- sge.ALIGN_TOP
- sge.ALIGN_BOTTOM
- sge.ALIGN_MIDDLE
- sge.Game.event_game_start
- sge.Game.event_game_end
- sge.Room.resume

Specification misc changes:
* Methods that previously used the "ALIGN" constants now use simple
  string representations ("left", "right", "center", "up", "down",
  "middle").
* xrepeat and yrepeat of sge.BackgroundLayer changed to repeat_left,
  repeat_right, repeat_up, and repeat_down.
* Background layers do not repeat by default.
* sge.Room.start no longer restarts the room.  This behavior was very
  difficult to maintain, and considering it can be achieved by just
  creating a new room, it isn't worth it.
* sge.Game.start no longer has a secondary function of restarting the
  game.  This effect can be achieved easily enough just by starting the
  first room.


0.15
------------------------------------------------------------------------

Specification removals:
- sge.image_directories
- sge.font_directories
- sge.sound_directories
- sge.music_directories

Specification misc changes:
* Images loaded for sge.Sprite objects are now loaded from a directory
  specified by the new "directory" argument.
* Fonts, sounds, and music now have their exact path names specified,
  rather than implicitly searching a certain set of directories.
* sge.Color now supports indicating alpha values in HTML-style hex
  strings.


0.14
------------------------------------------------------------------------

Specification additions:
+ sge.Sprite.draw_polygon
+ sge.Game.project_polygon
+ sge.Room.project_polygon
+ sge.Background.rd
+ sge.BackgroundLayer.rd
+ sge.Font.rd
+ sge.Music.rd
+ sge.Object.rd
+ sge.Room.rd
+ sge.Sound.rd
+ sge.Sprite.rd
+ sge.View.rd
+ sge.Game.start_room
+ sge.Game.alarm
+ sge.Room.alarm
+ sge.Object.alarm

Specification removals:
- sge.Game.sprites
- sge.Game.background_layers
- sge.Game.backgrounds
- sge.Game.fonts
- sge.Game.sounds
- sge.Game.music
- sge.Game.objects
- sge.Sprite.id
- sge.BackgroundLayer.id
- sge.Background.id
- sge.Font.id
- sge.Sound.id
- sge.Music.id
- sge.Object.id
- sge.Sprite.destroy
- sge.BackgroundLayer.destroy
- sge.Background.destroy
- sge.Font.destroy
- sge.Sound.destroy
- sge.Music.destroy
- sge.Object.alive
- sge.Game.rooms
- sge.Room.room_number
- sge.Room.end
- sge.Game.registered_classes
- sge.Game.register_class
- sge.Room.objects_by_class
- sge.Game.set_alarm
- sge.Game.get_alarm
- sge.Room.set_alarm
- sge.Room.get_alarm
- sge.Object.set_alarm
- sge.Object.get_alarm

Specification misc changes:
* sge.Object.destroy now simply removes the object from the current room.
* Definition of sge.Object.event_create made more explicit.
* sge.Object.event_destroy is now only called when the object is removed
  from the current room.
* "Naming Conventions" from "SGE Concepts" removed; it is now obsolete.
* The starting room is no longer implicitly the first one which was
  created.  Instead, you must assign the starting room explicitly to
  sge.game.start_room.
* sge.Room.start and sge.Room.resume now support transitions.


0.13
------------------------------------------------------------------------

Specification additions:
+ sge.Object.alive
+ sge.Room.remove

Specification misc changes:
* Clarified that the create and destroy events occur right after
  creation and destruction of the object.


0.12
------------------------------------------------------------------------

Specification additions:
+ sge.View.wport
+ sge.View.hport
+ sge.mouse.set_x
+ sge.mouse.set_y

Specification misc changes:
* sge.game.mouse is not used for as many jobs as it was previously.
* Mouse position attributes are -1 if the mouse is in relative mode.


0.11
------------------------------------------------------------------------

Specification additions:
+ sge.Color

Specification misc changes:
* Colors are specified by objects of the new sge.Color class rather than
  arbitrary kinds of values.
* sge.StellarClass renamed to sge.Object.
* Name changed from "Stellar Game Engine" to "SGE Game Engine".


0.10
------------------------------------------------------------------------

Specification additions:
+ sge.Game.set_alarm
+ sge.Game.get_alarm
+ sge.Game.event_alarm
+ sge.Room.set_alarm
+ sge.Room.get_alarm
+ sge.Room.event_alarm
+ sge.Sprite.draw_erase
+ sge.StellarClass.checks_collisions
+ sge.StellarClass.tangible
+ sge.Game.collision_events_enabled
+ sge.keyboard.get_pressed
+ sge.keyboard.get_modifier
+ sge.keyboard.get_focused
+ sge.keyboard.set_repeat
+ sge.keyboard.get_repeat_enabled
+ sge.keyboard.get_repeat_interval
+ sge.keyboard.get_repeat_delay
+ sge.mouse.get_pressed
+ sge.joystick.get_axis
+ sge.joystick.get_hat_x
+ sge.joystick.get_hat_y
+ sge.joystick.get_pressed
+ sge.joystick.get_joysticks
+ sge.joystick.get_name
+ sge.joystick.get_id
+ sge.joystick.get_axes
+ sge.joystick.get_hats
+ sge.joystick.get_trackballs
+ sge.joystick.get_buttons
+ sge.mouse.get_x
+ sge.mouse.get_y
+ sge.Game.input_events
+ sge.Game.pump_input
+ sge.Game.regulate_speed
+ sge.Game.refresh
+ sge.input.KeyPress
+ sge.input.KeyRelease
+ sge.input.MouseMove
+ sge.input.MouseButtonPress
+ sge.input.MouseButtonRelease
+ sge.input.JoystickAxisMove
+ sge.input.JoystickHatMove
+ sge.input.JoystickTrackballMove
+ sge.input.JoystickButtonPress
+ sge.input.JoystickButtonRelease
+ sge.input.KeyboardFocusGain
+ sge.input.KeyboardFocusLose
+ sge.input.MouseFocusGain
+ sge.input.MouseFocusLose
+ sge.input.QuitRequest
+ sge.Sprite.draw_lock
+ sge.Sprite.draw_unlock
+ sge.Font.get_width
+ sge.Font.get_height
+ sge.joystick.refresh

Specification removals:
- sge.StellarClass.detects_collisions
- sge.get_key_pressed
- sge.get_mouse_button_pressed
- sge.get_joystick_axis
- sge.get_joystick_hat
- sge.get_joystick_id
- sge.get_joystick_axes
- sge.get_joystick_hats
- sge.get_joystick_trackballs
- sge.get_joystick_buttons
- sge.Font.get_size
- sge.show_message
- sge.get_text_entry

Specification misc changes:
* sge.Room.event_room_resume no longer calls sge.Room.event_room_start by default.
* "name" and "ID" arguments for joystick events renamed to "js_name" and
  "js_id", respectively.
* IMPLEMENTATION set to "SGE Specification" instead of "SGE Template".


0.9
------------------------------------------------------------------------

Specification additions:
+ sge.collision.rectangles_collide
+ sge.collision.masks_collide
+ sge.StellarClass.regulate_origin
+ sge.StellarClass.image_origin_x
+ sge.StellarClass.image_origin_y
+ sge.StellarClass.mask
+ sge.StellarClass.mask_x
+ sge.StellarClass.mask_y
+ sge.StellarClass.collision
+ sge.collision.rectangle
+ sge.collision.ellipse
+ sge.collision.circle
+ sge.collision.line
+ sge.StellarClass.event_update_position

Specification removals:
- sge.StellarClass.collides

Specification misc changes:
* Rotation and scaling are no longer relative to the origin unless the
  new regulate_origin attribute is True.
* New attributes added to sge.StellarClass.__init__'s arguments.
* transparent argument moved in front of origin_x argument in sge.Sprite.__init__.
* Step events now have a "delta_mult" argument.


0.8
------------------------------------------------------------------------

Specification additions:
+ sge.Sprite.frames
+ sge.Sprite.append_frame
+ sge.Sprite.insert_frame
+ sge.Sprite.delete_frame
+ sge.Sprite.from_tileset
+ sge.Sprite.destroy
+ sge.BackgroundLayer.destroy
+ sge.Background.destroy
+ sge.Sound.destroy
+ sge.Music.destroy
+ sge.Room.destroy
+ sge.Room.move
+ sge.Game.project_dot
+ sge.Game.project_line
+ sge.Game.project_rectangle
+ sge.Game.project_ellipse
+ sge.Game.project_circle
+ sge.Game.project_sprite
+ sge.Game.project_text

Specification misc changes:
* room_number argument added to sge.Room.__init__


0.7
------------------------------------------------------------------------

Specification additions:
+ sge.get_joystick_name
+ sge.get_joystick_id
+ sge.get_joystick_trackballs
+ sge.Game.register_class
+ sge.Game.registered_classes
+ sge.Room.objects_by_class
+ sge.StellarClass.event_begin_step
+ sge.StellarClass.event_end_step
+ sge.StellarClass.event_inactive_end_step
+ sge.Sprite.speed
+ sge.StellarClass.image_speed

Specification misc changes:
* Joystick handling functions now accept joystick names for "joystick" argument.
* Joystick events' "joystick" argument renamed to "ID".
* Joystick events now have a "name" argument indicating the joystick name.
* sge.Room.objects changed from a tuple to a list.
* xprevious and yprevious of StellarClass now indicate the x and y
  values of the previous frame rather than the last x and y values
  different from the current ones.
* Changing sge.Sprite.width and sge.Sprite.height is now officially destructive.


0.6
------------------------------------------------------------------------

Specification additions:
+ sge.Font.from_sprite
+ sge.Room.event_room_resume

Specification misc changes:
* sge.Sprite.draw_sprite and sge.Room.project_sprite now support blend modes.
* sge.Sound.play and sge.Music.play "loops" argument tweaked.

Specification bugfixes:
- Argument for Font.__init__ being the old "id_" rather than "ID"
- Small problems with the documentation


0.5
------------------------------------------------------------------------

Specification additions:
+ sge.Game.event_gain_keyboard_focus
+ sge.Game.event_lose_keyboard_focus
+ sge.Game.event_gain_mouse_focus
+ sge.Game.event_lose_mouse_focus
+ sge.Game.event_paused_gain_keyboard_focus
+ sge.Game.event_paused_lose_keyboard_focus
+ sge.Game.event_paused_gain_mouse_focus
+ sge.Game.event_paused_lose_mouse_focus
+ sge.Room.event_gain_keyboard_focus
+ sge.Room.event_lose_keyboard_focus
+ sge.Room.event_gain_mouse_focus
+ sge.Room.event_lose_mouse_focus
+ sge.Room.event_paused_gain_keyboard_focus
+ sge.Room.event_paused_lose_keyboard_focus
+ sge.Room.event_paused_gain_mouse_focus
+ sge.Room.event_paused_lose_mouse_focus

Specification misc changes:
* Documentation reformatted.
* "id"/"id_" argument in many constructor methods changed to "ID".


0.4
------------------------------------------------------------------------

Specification additions:
+ sge.Sprite.from_screenshot
+ sge.Sprite.save
+ sge.show_message
+ sge.get_text_entry
+ sge.Room.background_x
+ sge.Room.background_y
+ sge.Sprite.id
+ sge.BackgroundLayer.id
+ sge.Font.id
+ sge.Sound.id
+ sge.Music.id

Specification removals:
- sge.Music.stop_all (replaced by sge.Music.stop, now a static method)
- sge.Music.balance (nonsensical; should be controlled by the music file)
- sge.Sound.balance (replaced by a balance argument when the sound is played)
- sge.Background.x (replaced by sge.Room.background_x)
- sge.Background.y (replaced by sge.Room.background_y)

Specification misc changes:
* bbox_x and bbox_y of sge.Sprite now default to the top-left of the image.
* sge.Music.stop is now a static method.
* sge.Music.pause is now a static method.
* sge.Music.unpause is now a static method.
* Key press events now have a third argument, char.
* sge.Sound.play now has a balance argument.
* Docstrings reformatted to reStructuredText.
* sge.Sprite.__init__ now has an id attribute.
* sge.BackgroundLayer.__init__ now has an id attribute.
* sge.Font.__init__ now has an id attribute.
* Sprites can be referenced by id rather than by name now.
* Background layers can be referenced by id rather than by sprite name now.
* Fonts can be referenced by id rather than by name now.

Specification misc changes:
* Released to the public domain via CC0.


0.3
------------------------------------------------------------------------

Specification additions:
+ sge.Room.project_dot
+ sge.Room.project_line
+ sge.Room.project_rectangle
+ sge.Room.project_ellipse
+ sge.Room.project_circle
+ sge.Room.project_sprite
+ sge.Room.project_text
+ sge.Background.x
+ sge.Background.y
+ Trackball support
+ sge.StellarClass.active

Specification misc changes:
* Trying to load invalid sound files now raises an exception.
* The file name for sounds and music can now be set to None for null sounds.
* Mouse buttons are now identified by strings instead of constants.


0.2.1
------------------------------------------------------------------------

Specification misc changes:
* sge.Game.window_icon is now a file name instead of a sprite.
* The default room size is now the game window size.


0.2.0
------------------------------------------------------------------------

Specification additions:
+ sge.Sprite.draw_dot
+ sge.Sprite.draw_line
+ sge.Sprite.draw_rectangle
+ sge.Sprite.draw_ellipse
+ sge.Sprite.draw_circle
+ sge.Sprite.draw_text
+ sge.Sprite.draw_clear
+ sge.Game.grab_input
+ sge.Sprite.draw_sprite
+ sge.Music.clear_queue
+ sge.Music.stop_all
+ sge.Sound.stop_all
+ sge.StellarClass.create
+ sge.Game.window_text
+ sge.Game.window_icon

Specification removals:
- sge.Game.draw_dot (replaced by sge.Sprite.draw_dot)
- sge.Game.draw_line (replaced by sge.Sprite.draw_line)
- sge.Game.draw_rectangle (replaced by sge.Sprite.draw_rectangle)
- sge.Game.draw_ellipse (replaced by sge.Sprite.draw_ellipse)
- sge.Game.draw_circle (replaced by sge.Sprite.draw_circle)
- sge.Game.sound_stop_all (replaced by sge.sound_stop_all)

Specification misc changes:
* A list or tuple of possible font choices can now be specified.
* Sprites now use a transparent image by default, not a black image.
* Added arguments to sge.Room.end.
* Implementations no longer required to support Ogg Vorbis and WAV.
* Removed unnecessary arguments from sge.Font.get_size.
* Split SGE in to multiple files.


0.1.0
------------------------------------------------------------------------

First release
