  Change Log

V3.4.3 - June 2026
------------------
  Bug fixes:

* Make animation work when only frame()/ftime() are used and no time
adjustments.
* Fix SVG stroke line-caps and line-joins.
* Win: Unicode character insertion commands were corrupted.
* Win: CFDG files were displayed as if they were in Windows code
page 1252 instead of UTF8.
* frame() function did not have correct semantics for looping
animation. The first and last frames were always identical, resulting
in a stutter. Added CF::Looping configuration variable to change the 
range of frame() from [0,1] to [0,1).

V3.4.2 - July 2024 (Linux)/March 2025(rest)
-------------------------------------------
* Support FFmpeg 7.0 API change
* Win: Installs on Intel and Arm systems. Has been rewritten as an MFC application.

  Bug fixes:

* Mac: Bold and italic styling restored in the text editor.
* Mac: Context Free would permit movie sizes that AV Foundation rejects. Now it 
  enforces the correct requirements (multiple of 16 pixel width, even height).
* Mac: Context Free would accumulate blank Untitled windows as it was quit and restarted.

V3.4.1 - February 2023
----------------------
  Bug fixes:

* Random number generator was broken in v3.4. v3.3 variations are now restored.

V3.4 - February 2023
--------------------
* startshape is now optional. If there is no startshape then the first shape or 
  path with no parameters is selected as the startshape. This is primarily useful 
  for code golf, where every byte counts.
* Win: Native support for Arm64 CPUs added. Application has been rewritten in C#. 
  Should behave the same as previous versions.

  Bug fixes:

* Multiple flags work for path operations, as they do for path commands and shape replacements.

V3.3.1 - January 2021
---------------------
* Mac: Universal application natively supports Apple Silicon.

  Bug fixes:

* Win: Fixed crash after closing a tab and then opening the File menu, or changing the editor font or style.
* Mac: Fixed synchronization in animation viewer looping/non-looping checkbox and viewer internal state.

V3.3 - April 2020
-----------------
* Color blending modes using a new blend adjustment have been added. They work like the 
  CSS color blending modes except that hue, saturation, color, and luminosity modes are 
  not provided. The Porter-Duff Clear, Plus, and Xor compositing modes have also been 
  added, as they seemed useful.
* Animation preview can now loop the animation.
* Command-line version can now invoke a display executable to view png, svg, or QuickTime 
  output. This facilitates integration of Context Free with editor tools. A cfdg build 
  system for Sublime Text on a Mac might look like:

    {
        "cmd": ["/usr/local/bin/cfdg", "--display=/usr/bin/open", "$file"],
        "file_regex": "^([^\n:]+):([0-9]+):([0-9]+): (error: .+)$"
    }

  Bug fixes:

* Animation of tiled/frieze designs did not work if the design used the ftime() or frame() functions.

V3.2 - July 2019
----------------
* -D option added to Posix and Windows command-line versions. This option permits the 
  declaration of global scope values from the command line. The values can be numbers, vectors,
  shapes, adjustments, configuration declarations, or function declarations.

  Bug fixes:

* Fixed Windows bug where gallery uploader tries to upload to the debug gallery server, 
  not to www.contextfreeart.org.
* Fixed bug where the gallery uploader crashes Context Free if it cannot connect to the server.

V3.1 - January 2019
-------------------
* Editor upgraded to the Scintilla cross-platform code editor. Context Free now has syntax
  highlighting, auto-completion, auto indentation, and more.
* Uploads to and downloads from the new Gallery API at https://www.contextfreeart.org/index.html
* Command-line version adds a feature to output the abstract syntax tree (AST) of a parsed cfdg 
  file as a JSON object.
* Action bar at the top of the window has more capabilities.
* Update gallery uploader to use v4 Creative Commons licenses.
* Supports macOS Mojave dark mode.
* All Unicode identifiers (shape, variable, and function names) are normalized so that 
  if they look the same then they will be treated as the same (NFKC normalization).
* You can set the tags when you upload a cfdg from Context Free and it even does auto-
  completion to help reuse tags and prevent typos.

  Bug fixes:

* Some code changes used methods that are not supported on OSX Lion (10.7), causing 
  Context Free to crash on those systems.
* Typos in example cfdg files fixed.
* Better input sanitization so that ill-formed cfdg code cannot crash Context Free.
* Context Free may issue false warnings about time or Z changes not being allowed
  inside paths if the time or Z change is in a global variable and at least one path
  exists in the file.

V3.0.11.4 - July 2017
---------------------
* Including examples in version 2 cfdg files includes the version 2 variant
  of the example.
* The missing shape rule error message now says where the problem is.

  Bug fixes:

* Fix handling of Mac OS9 line endings.
* Mac: Gallery upload sheet fails to display if the user has no stored 
  credentials.
* Mac: Tiled designs save/upload at the wrong resolution on systems with
  retina displays.

V3.0.11.3 - June 2017
---------------------
* Makefile updated to match Debian conventions.

  Bug fixes:

* Mac: Crash on rendering files with errors.
* Mac: Render sub-window collapsed or set to a random size.
* CF::AllowOverlap was not being processed at the right time to suppress 
  overlap warnings.
* Makefile failing to work in many situations.

V3.0.11 - June 2017
-------------------
* Animation has changed from an output save option to a first-class operation. 
  You do not need to render first to generate a movie. Instead, select the 
  Animate command from the Render menu. You will be shown a preview of the 
  movie.
* Individual movie frames can also be rendered, for testing. Select Animate 
  Frame command from the Render menu, or use the --frame option on the command 
  line.
* Windows, command-line: Movie output now uses the H.264 or the ProRes format. 
  Support for Apple Animation codec is removed.
* Windows: User interface has been updated to a more modern look.
* Mac: Some open-source code with an insufficiently free license has been 
  replaced with completely free code. This should satisfy a Debian bug filed on 
  Context Free.
* A variable named π (pi) has been defined with the expected value. An entry 
  in the Insert Character sub-menu has been added.
* It is now possible to multiply or divide a vector by scalar value and each 
  element will be multiplied or divided by that value. Vectors can also be 
  multiplied by divided by vectors of the same size; element by element 
  multiplication or division will result.
* command line: The example cfdg files have been embedded in the command-line 
  version, just as they are in the GUI versions. They can be imported into 
  other designs in any version.

  Bug fixes:
  
* Improperly terminated comments could cause Context Free/cfdg to hang.
* A spurious error, "Invalid UTF-8 encoding: ASCII null character", can be 
  reported for valid cfdg input if a shape name is the very last token in a 
  cfdg file.
* Cfdg files that only have FILL shapes in them and no SQUAREs, CIRCLEs, 
  TRIANGLEs, or paths will fail to draw anything.
* A dependency on Bison 3.03 was accidentally introduced. Context Free/cfdg is 
  supposed to depend on Bison 2.5.

V3.0.10 - January 2017
----------------------

* Uploading from Context Free now uses HTTPS instead of HTTP, which 
  www.contextfreeart.org now requires. Context Free also stores your password 
  encrypted.

  Bug fixes:
  
* Shape adjustments of the form x expr1 y expr2 are not evaluated correctly if 
  expr2 is random or depends on a shape parameter and expr1 does not.
* The case values in switch statements are supposed allow for arbitrary 
  constant expressions, but anything except an integer constant produces an 
  error.
* fixed (command-line): Sometimes crashes while generating animation output.

v3.0.9 - May 2015
-----------------

* New random distribution functions added.

  Bug fixes:
  
* Crashes when there is a typo in a function name
* Crashes when shapes or paths take rules as parameters under certain esoteric 
  conditions
* Perfectly symmetric self-intersecting paths will get silently dropped.
* Symmetry groups pm, pg, pmg, and cm are broken.

v3.0.8 - June 2014
------------------

* Errors that occur during SVG file output are reported to the user. Previously 
  they were silent.

  Bug Fixes:
  
* OS X: Some automatic text substitutions are occurring in the cfdg edit box. 
  The proper subtraction operator is being converted to an m-dash.
* Windows: SVG files cannot be saved.

v3.0.7 - May 2014
-----------------

  Bug Fixes:
  
* OS X: Random crash while rendering tiled cfdg files
* Parser error confuses the colon in switch statement case and else bodies with 
  the colons used for namespaces.

v3.0.6 - February 2014
----------------------

* The maximum length for vectors is increased from 9 to 99.

  Bug Fixes:
  
* A memory leak can fill memory with parameter blocks, causing Context Free to 
  crash.
* Modification terms of the form x 1 1 n get silently converted to z n. The 
  x 1 1 gets dropped.
* Transform and clone statements with non-constant symmetry arguments cause 
  Context Free to crash
* Configuration variables that depend on global variables fail if the global 
  variable is not constant
* Windows: Color calculator generates incorrect CFDG code in locales where the 
  decimal mark is a comma.
* Windows: Incorrect text (or no text) in some dialog fields can trigger an 
  uncaught exception.

v3.0.5 - January 2013
---------------------

* Variable name shadowing rules have been relaxed. A variable can have the same 
  name as a variable in an outer level of scope.
* Windows: Performance improved for designs with many shapes.
* Windows: Context Free properly registers for handling cfdg files.
* Two-value color targets and stateful color targets can be used together in 
  the same version 2 cfdg file.

  Bug fixes:
  
* Crash when parsing version 2 paths.
* User interface hangs for designs with many, many shapes.
* User interface hangs for designs with very long running rules.
* Negative brightness, saturation, and alpha adjustments work correctly in 
  adjustment variables and parameters.
* Crash when closing a window that had temporary files associated with it on 
  OS X.
* FILL primitive shape is no longer duplicated by CF::Symmetry operations.
* Makefile references libm.
* Crash when multiplying output vertically (Posix and Windows CLI).

v3.0.4 - December 2012
----------------------

* User interface hangs have been fixed for designs with many, many shapes
* User interface hangs have been fixed for designs with very long running rules
* Variable name shadowing rules have been relaxed. A variable can have the same 
  name as a variable in an outer level of scope.
* W: Performance improved for designs with many shapes
* W: Context Free properly registers for handling cfdg files.

v3.0.3 (Windows only) - November 2012
-------------------------------------

* Works with Windows 8
* Windows GUi and CLI versions now generate random variations

v3.0.2 - October 2012
---------------------

* Switched to FFmpeg version 1.0
* Command line versions can now properly stream output to standard out, even a 
  stream of animation frames to ffMPEG

  Bug fixes:
  
* Unix version does not center uncropped images.
* Crashes on OS X versions other than Mountain Lion.

v3.0.1 - September 2012
-----------------------

  Bug fixes:
  
* Functions with vector arguments don't work
* let() function inside a user function fails
* Windows command-line version reports the wrong version number
* Memory corruption occurs if the background is not opaque, results in random 
  errors
* Visible seams on tiled images that have very small shapes at the tile edge
* Variations totally broken due to uninitialized data bug
* Command-line version cannot generate anything but QuickTime output, see 
  https://www.contextfreeart.org/phpbb/viewtopic.php?f=10&t=968#p3683

v3 - June 2012
--------------

* Parameters for rules and paths (which can be numbers, shape adjustments, or 
  shape specifications)
* Random number function that has a different value each time a rule is 
  executed.
* Local and global variables
* Loop variables
* Loop finally blocks, executing code at the tail end of a loop
* Conditional expressions: the select() and if() functions. It works like the C 
  ?: operator, but over multiple values
* Conditional code: switch statements and if statements
* Included files can be placed in their own namespace to prevent name collisions
* Numeric parameters are restricted to prevent creation of context-sensitive 
  grammars
* The color target feature has been replaced with something that provides the 
  same benefit but is less confusing.
* Shape time, allows you to specify which frames a shape is visible in during 
  movie generation
* New FILL primitive shape, fills the canvas with the specified color at the 
  specified Z. Similar to the background, but you can interleaves shapes and 
  FILLs in Z.
* 16-bit color depth
* M, W: Compiler and run-time messages now have a window instead of flying by 
  on the status bar
* M, W: Remembers window size
* M, W: Edit->Insert menus for inserting Unicode characters or CF:: names
* time() function, allows shapes to change from frame to frame in a movie
* 64-bit
* User-defined functions, can be recursive, mutually recursive, return multiple 
  values
* Bit manipulation functions
* More symmetry options: 1-dimensional tiling and frieze group, rotational and 
  dihedral symmetry, wallpaper group

v2.2.2 - September 2010
-----------------------

  Bug Fixes:

* M: Fix display error on Mac OS x 10.6 (Snow Leopard)
* M: Fix code for handling non-ASCII characters in file names.
* W: Restore Find/Replace function that was accidentally dropped in version 2.2
* W: Remember window size.

v2.2.1 - August 2009
--------------------

  Bug Fixes:

* Typos in path operation and commands will be flagged as such.
* W: When uploading to the gallery the actual contents of the cfdg editor 
  window will be uploaded.
* W: Crash during upload to gallery under Windows 7 is fixed.
* W: Layout errors under Windows 7 in the Save Image and Save Movie dialogs 
  fixed.
* P: PNG file colors are not pre-multiplied against the alpha channel.

v2.2 - January 2009
-------------------

* Optional size directive lets you crop your design
* Paths for user-defined primitive shapes
* Expressions
* Extensions to Loops
* Mac and Windows clients support 6-letter variation codes
* New client for the Windows command line
* Windows client ported from MFC framework to .NET 2.0 framework, should 
  compile with (free) Visual Studio Express 2005
* Ability to set a Creative Commons license for use when uploading designs
* Stronger random number generator used for picking random variations
* Quiet mode for Posix and Windows command line clients suppress non-error 
  output
* Option to insert variation code in output file names and also to change how 
  animation frame numbers are inserted
* Included file names can be in double quotes, which allows for spaces in file 
  names and file names that do not end in .cfdg
* SVG file shapes are flattened so that they can be edited in Inkscape

  Disappearing Features:

* Rule names cannot contain '-' or '.'
* Rule names cannot begin with a digit
* The following rules names are no longer allowed: path, MOVETO, LINETO, ARCTO, 
  CURVETO, MOVEREL, LINEREL, ARCREL, CURVEREL, and CLOSEPOLY, x1, x2, y1, y2, 
  rx, ry, p, param, width
* Included file names must end with a .cfdg extension, be in the same directory 
  as the original cfdg file, and contain no spaces, unless the file name is in 
  double quotes

  Bug Fixes:

* variation code spinner control wraps properly between variation A and 
  variation ZZZZZZ
* i_curves.cfdg rule names are now legal
* very large shapes were not tiling properly
* variations work the same on big-endian (PowerPC) and little-endian (x86) 
  systems. Big-endian variations are still available.
* Proper GPLv2 copyright notices are present in all files
* QuickTime movies with transparent backgrounds work
* Propagated alpha computation fix from 32-bit pixel formats to 24 and 8-bit 
  pixel formats
* Some warnings generated by GCC 4.3 have been fixed
* Very large bezier curves do not blow up the memory requirements
* W: tiled animations were not working
* P: crash case on malformed cfdg files from standard input fixed

  Known Issues:

* If you have a typo in a path operation or path command (e.g., moveto instead 
  of MOVETO) then it will be treated as a FILL path command. The proper 
  treatment should be to list it as an unrecognized path operation/command.
* W: When uploading to the gallery, if you change the cfdg text in the edit 
  window after rendering then the changed text will not be uploaded to the 
  gallery. Context Free under Windows takes a snap-shot of the cfdg text each 
  time it is rendered and this snap-shot is what is uploaded. The work-around 
  is to re-render before uploading to the gallery.
* W: Crashes during upload to gallery under Windows 7 RC1. This will probably 
  force a minor release.
* P: Images with transparent backgrounds are stored in the PNG file with 
  pre-multiplied alpha, but the PNG specification says to use non-premultiplied 
  alpha.

v2.1 - April 2007
-----------------

* Tiled rendering for cfdg mosaics
* W,M Tiled cfdgs will display as tiled
* W,M If the tile transform is skewed then Context Free can save a superset of 
  the tile unit to form a rectangular grid
* P You can pipe a cfdg file into cfdg on stdin
* P cfdg uses 6 letter variation codes, Context Free still uses 3 letter codes
* W,M You can upload directly from Context Free to the gallery site
* W The color calculator is completely revamped to be easier to use (and the 
  code is less hideous now)
* W Instead of installing a local copy of the runtime DLLs (always a bad idea), 
  the Windows runtime installer is executed from the Context Free installer
* Only generates 32-bit PNG files if the background is non-opaque, otherwise 
  generates 8- or 24-bit PNG files
* Upgraded from AGG 2.3 to AGG 2.5

  Bug Fixes:

* non-opaque shapes composited correctly
* startshape, tile, and background directives after the first are now ignored
* M Fixed URLs in help menu
* P Makefile fixes for various Unix/Linux
* W Fixed bug in registration of .cfdg file extension
* W,M cfdg files with spaces in the file name can be uploaded

v2.0 - September 2006
---------------------

* New output formats: QuickTime movies, SVG vector graphics, and JPEG (Windows 
  only)
* Ability to control size of border around images
* Z-axis support for controlling which shapes go on top and which go behind.
* Simple loop syntax to eliminate tedious repetition of shapes
* More predictable rendering algorithm: always renders the largest shape
* Performance improved by profiling and refactoring
* W Migrated to Visual Studio 2005

  Bug fixes:

* Transparent backgrounds are now handled correctly
* Doesn't crash with infinitely increasing cfdg files
* Variations are now consistent across all platforms and compilers
* W Cropped image save works
* W Find/Replace works
* M dialog edit control bug fixed
* M SVG file save works

v1.2 - September 2005
---------------------

* Fixed shape render ordering bug when shapes spill to temporary files.
* W Fixed PNG save file name issues with non-English versions of Windows.

v1.2 experimental - July & August 2005
--------------------------------------

* Support for color and alpha: See Announcements forum for details
* Welcome.cfdg colorized
* Added Rose.cfdg color example
* Optimized finished shape memory usage (faster temporary file operations)
* Fixed bugs in rendering size adjustment which caused some ellipses to look 
  like polygons, and some shapes to not align correctly
* W,M Added Color Picker / Calculator for helping to compute color adjustment 
  values
* M Temporary fix for Render with dimensions dialog bug: Removed thousands 
  separator.
* Fixed bug in hue conversion that caused black shapes. (fixed 7/28)

  changes in August 5th update:

* Black shape bug fixed
* Added background syntax
* Removed '=' syntax for hue, sat, brightness, and alpha
* Added limit syntax for hue, sat, brightness, and alpha
* Removed startshape parameters
* W Color Picker matches same functionality of Mac Color Calculator

v1.1 - July 2005
----------------

* Simple adjustment code replaced with general affine transform code and new 
  transforms added: anisotropic scaling, skew (shear), and reflection
* New syntax for controlling the order that the affine transforms are applied
* Equilateral triangles added
* Circle/ellipse code sped-up
* Digits added to i_pix.cfdg, Chris' i_polygons.cfdg added
* W,M Lesson files put in Help menu as well
* W New status icon
* W Opening a given example twice gives the second a unique name
* P Missing include files added

v1.0.3 - June 2005
------------------

* W Fixed a crash when trying to open a non-existent file
* W Opening examples no longer affects the recently-used files list

v1.0.2 - May 2005
-----------------

* W Fixed some crashes with Untitled and unrendered documents
* W Increated max image size to 32768x32768 pixels

v1.0 - May 2005
---------------

* Rendering with the Anti-Grain Geometry library: Looks equally incredible on 
  all platforms!
* Fix bug when no shapes are rendered: reported image size is reasonable
* Images properly centered in all cases on all platforms
* W Better display of generated images that are larger than the window
* W Empty documents don't try to auto-render
* W Smooth drawing during window resize
* W Render-to-size settings are now persistent
* P Oversampling (-x) option removed, as AGG rendering is anti-aliased
* P Fixed bug with height option (-h), it now works
* P Build is optimized (-O3)

v0.9 beta2 - May 2005
---------------------

* W Fixed error in coordinate handling that incorrectly cropped images
* W Cropping is now a rendering option, not a save option
* W Fixed bug in MDI framework code
* W Significant performance and UI enhancements when rendering very large images

v0.9 beta - May 2005
--------------------

* Improved temp file handling and reporting
* Report syntax errors in libraries with correct line number
* Fine tuning of rendering operations for each platform
* Many more examples
* W,M On syntax error: high-light line with error
* W,M New application icon (subtle)
* M About box links now work
* M Rendering dimensions must now be at least 32x32
* W On Windows XP, use new user interface look
* W MDI application with tabbed interface
* W Support open documents from Explorer when already running
* W Top bar dynamically adjusts
* W Render with GDI+, looks much better and huge dimensions work (we've done 
  10k x 10k!)
* W Variation controls
* W Rendering commands (menus, context menus, dialogs) improved
* W Image cropping option on save
* W Added user preferences
* W Integration with shell finally works
* P Anti-aliasing via over-sampling
* P New command line processing and options: save cropped, over-sample rate & 
  variation code

v0.2.2 alpha - May 2005
-----------------------

* W Fixed failure to load on Windows 98/Me
* M Fixed crash on second "Save Image" command
* M Show cropped image size in status bar
* M Added "Send Feedback..." to Help menu
* Improved cropped rectangle calculation
  
