[ACT-R-users] New ACT-R 6.0 release

[db30 at andrew.cmu.edu]

ACT-R 6.0 v1.5 [r1577] is now the current version on the ACT-R web site.

This update is mostly minor bug fixes, but here are a couple of things
that are worth noting:

- The vision module now sets the default distance of visual-location
chunks in pixels instead of inches based on :viewing-distance and
:pixels-per-inch because the determination of nearest uses the distance
values so everything should be in the same units.

- The default devices were updated to be more consistent in the features
they produce for button and text items, but there will still be differences
based on different font metrics for real interface windows.

- Updates to the ccl-cocoa device by Clayton Stanley.  Most of the
improvements focused on enabling more intuitive and consistent keyboard
navigation between views in the window. A #\tab cycles focus between the
views, #\shift+#\tab cycles backwards, #\space when the focused view is
a button fires the action for that button, etc. This was all implemented
in a way where the model has to essentially 'enable' this sort of
navigation (space bar to fire a button in particular) by first pressing
#\tab on the window, so that one of the buttons has focus (instead of the
window). So this all should be implemented in a way that has no impact on
any prior or future models that - for instance - use #\space to do
something when the (default) window has focus.

- Added a collection of extensions for the motor module that have been
used for various tasks in /extras/extended-motor-actions.  Those extensions
include: holding and releasing actions for keys, buffers for tracking hands
individually, and more high-level 'press-key like' actions.

- Added some very speculative code which can take advantage of multiple
cores in a machine (when supported within a Lisp) that can be used to
perform things like finding chunks and computing activations in parallel.
For many models (all those in the tutorial and several other of the test
models) the overhead outweighs the benefit, but there may be situations
where it provides an improvement.  It can be found in
/extras/parallel-execution.


For details on what else has changed, you can view the commit log on the
ACT-R web site:

<http://act-r.psy.cmu.edu/log/actr6log.txt>


If you have any comments, questions, or problems with this update please
let me know.

Dan