eighty-twenty news

Chicken SDL v0.4.51117.0

A new release of chicken-sdl is available from our code repository. You can download the egg file here.

Interesting changes include:

Switch to Chicken 2.x conventions for invoking syntax-case.

From TLA to Darcs

I've finally gotten around to moving many of our TLA archives over to Darcs. I simply sealed the TLA versions and imported the sealed snapshot into Darcs, without transferring the history.

The main public projects I've darcsified are chicken-sdl and gyre (which is the tool we use to publish this site).

Chicken Cairo 0.1.2 alpha

"Release early, release often," they say. In this spirit, another release of Chicken Scheme bindings for Cairo is available in our 2005 archive.

The egg file is available in releases.

2005-01-06 18:15:03 GMT Michael Bridgen <mikeb@lshift.net>      patch-8

    Summary:
      Added text and font extents
    Revision:
      chicken-cairo--dev--0.1--patch-8

    - cairo_text_extents_t and cairo_font_extents_t types
      These are not returned from a function, so we have to allocate
      them as a (GC-able) byte vector and make C think it's a spot of
      memory.
    - Functions for determining the extents of text and fonts.
    - Updated example



2004-12-04 17:52:21 GMT Tony Garnock-Jones <tonyg@lshift.net>   patch-7

    Summary:
      Adapt to chicken-sdl's recent case changes, and upcase the cairo binding too
    Revision:
      chicken-cairo--dev--0.1--patch-7

    A few constants changed to UPPER_CASE, both references to SDL
    constants, and the flags defined in cairo.scm. Also removed test-cairo
    from the Makefile - it doesn't need to be compiled now that we have
    sdl-csi.


2004-11-30 00:40:37 GMT Michael Bridgen <mikeb@squaremobius.net>        patch-6

    Summary:
      Font and text rendering
    Revision:
      chicken-cairo--dev--0.1--patch-6

    Just a start on these -- enough to see something painted, which is exciting.


2004-11-17 19:40:06 GMT Tony Garnock-Jones <tonyg@kcbbs.gen.nz> patch-5

    Summary:
      cairo.setup file, to make 'make install' (and the egg) work
    Revision:
      chicken-cairo--dev--0.1--patch-5



2004-11-15 22:33:03 GMT Michael Bridgen <mikeb@squaremobius.net>        patch-4

    Summary:
      Query functions
    Revision:
      chicken-cairo--dev--0.1--patch-4

    Might come in handy ('specially alpha)


2004-11-15 14:02:26 GMT Michael Bridgen <mikeb@squaremobius.net>        patch-3

    Summary:
      Matrix operations (untested)
    Revision:
      chicken-cairo--dev--0.1--patch-3

    Added the cairo_matrix_* functions -- untested, except for the 
    compilation unit test.

    Just a bunch of typing really.


2004-11-11 00:19:12 GMT Michael Bridgen <mikeb@squaremobius.net>        patch-2

    Summary:
      Some documentation and decorations
    Revision:
      chicken-cairo--dev--0.1--patch-2

    Added some documentation regarding obscure/non-obvious things;
    divided into sets of functions with headers for navigation.

GNU/Arch archives moved

I've cycled our GNU/arch archives to 2005, meaning that the previous archive link is wrong. To correct:

tla register-archive http://www.eighty-twenty.org/archives/2004
tla register-archive http://www.eighty-twenty.org/archives/2005

Chicken SDL v0.3p2

A new release of chicken-sdl is available from our arch archive. You can download the egg file here.

Interesting changes include:

Case changes: constant definitions are now in uppercase, matching the C API.
The SDL egg now supports SDL_net networking.
The sdl-csi program is now installed in the bin directory, as part of the normal installation of the egg
Added missing sdl-quit-sub-system parameter; added sdl-set-color-key! (thanks to Felix Winkelmann)
Added a sdl-pixel-format-bytes-per-pixel accessor (thanks to Sunnan)
Added getter/setter for SDL errors.
The *sdl-rect-nil* global has been replaced by #f.
The problem on MacOS X (and probably also Windows) regarding sdl-init has been better documented (in the README)

Chicken SDL v0.3p1

A new release of chicken-sdl is available from our arch archive. You can download the egg file here.

Below is the relevant part of the changelog:

2004-12-01 13:18:11 GMT Tony Garnock-Jones <tonyg@kcbbs.gen.nz>   patch-10

    Summary:
      Incorporate changes suggested by Alex Shinn
    Revision:
      chicken-sdl--main--0--patch-10

    - (sdl-fill-rect) is now generic in the kind of colour it expects -
      either an unsigned integer, or an SDL_Color structure.

    - Added procedures (ttf-size-text!) and (ttf-size-utf8!).


2004-11-19 16:38:01 GMT Tony Garnock-Jones <tonyg@lshift.net>     patch-9

    Summary:
      Returned TTF_Fonts now have a NULL check
    Revision:
      chicken-sdl--main--0--patch-9

    Previously, calling (ttf-open-font) when the path specified was
    invalid in some way would result in the construction of a ttf-font
    structure with a pointer value of #f, and there was no way of checking
    the success or failure of (ttf-open-font) without explicitly calling
    (ttf-font-pointer), which is bad style.

    I've changed the foreign-type wrap procedure to check for a #f pointer
    before constructing the ttf-font structure. If the pointer is #f, the
    whole result is #f - otherwise a ttf-font structure is built as usual.


2004-11-15 12:09:04 GMT Tony Garnock-Jones <tonyg@kcbbs.gen.nz>   patch-8

    Summary:
      Replace timer functionality
    Revision:
      chicken-sdl--main--0--patch-8

    It is problematic supporting SDL_AddTimer and SDL_RemoveTimer from
    chicken, since they a) are implemented using setitimer(2) and b)
    involve callbacks from C to Scheme. Each would be fine on its own, but
    taken together they interfere with the main Scheme thread.

    As it happens, the SDL_WaitEvent function is implemented in terms of
    polling (!) for events, with a short delay if none present themselves
    - the usual pragmatic tradeoff for event-based systems on Unix-like
    machines - and so we will be doing no worse if we do a similar thing
    ourselves. Hence, I've written a Scheme-based timer library which
    integrates with SDL's event loop, calling SDL_Delay(10) when there's
    no work just like SDL_WaitEvent.

    This does of course mean that the user must now either use
    (sdl-wait-event!), which manages timeouts itself, or must instead
    somehow arrange for periodic calls to (sdl-process-timer-queue!).

    The timer library is implemented in timer.scm, and depends on a
    leftist-heap implementation from heap.scm. These two modules ought
    probably to be split out into eggs of their own, and distributed as
    part of some kind of general utility library for chicken. For now,
    they're (include)d directly into sdl.scm, to avoid needing to install
    more than one file for this extension.

Chicken SDL and Chicken Cairo

For your consideration, alpha releases of SDL and Cairo bindings for Chicken Scheme.

SDL is a cross-platform library for accessing video, audio and HID events. Cairo is a vector-graphics library that happens to be easily integrated with SDL.

Both are available in our GNU/Arch archive at http://www.eighty-twenty.org/archives :
tla register-archive http://www.eighty-twenty.org/archives
tla abrowse arch@eighty-twenty.org-public--2004