Salabim

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Under the hood restructuring of classes, thus enabling overriding.

In order to support packaging (i.e make salabim a site_package), the simulation
environment is no longer automatically defined.
It is now necessary to make an environment in the application, by:
Environment()
The Environment class has now an extra argument, is_default_env, which is True by
default.
Also, the global variable random has been phased out. Instead, salabim uses now
the random class directly in all statistical sampling functions.
It is possible to set the seed of the random stream by means of
- random_seed()
- random.seed(), provided random is imported
- Environment(random_seed=...)
The standard random stream is now used in all distribution definitions, unless
a randomstream is explicitly specified.

Other than in previous versions, reproducibility is only available if
a random seed value is specified, usually when defining an Environment.

All sample programs are defined in such a way that they give reproducible results.

main is no longer a global variable. You can use either the main
property in Component or Environment classes or just main() from the
salabim module, e.g. with env.main()

The default environment can be queried with the function default_env(),
e.g. de=sim.default_env().

All sample filea are updated according to the new interface.

Font handling has been improved. It is now allowed to specify a font by the
file name or the descriptor, e.g.
'timesi' or 'Times New Roman Italic'.
The case is not important any more.
The function show_fonts() can be used to retrieve all currently available
font names (on this machine).

The salabim_install script now installs salabim in a more Pythonic way
in the site-packages folder.

Bug in slider function under Pythonista fixed.

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Bug in video production fixed.
Minor changes in the sample programs.

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The animation of all sample models is completely restructured in order to separate the simulation model
code from the animation code. This leads to much easier to read and debug models. Also the same code can now
be used for animation and production (non animated) applications.

Introduced an attribute 'mode' for components, which can be set either with an assignment or as a parameter of:
initialization of a component
passivate
activate
reactivate
hold
activate
standby
request
cancel
This attribute can be very useful for animations which run more or less separate from the simulation code.
The mode parameter may be any type, although str is possibly the most useful.
Also, the mode is now shown in a trace.

The attribute passive_reason has been phased out, as mode offers similar functionality for passive components. Be aware that mode is not reset automatically!

When the mode is set, either by an assignment or one of the above methods, the property mode_time is
set to now. This is particularly useful for hold, in order to assess when the component started the
hold, like in
fraction=sim.interpolate(env.now,comp.mode_time,comp.scheduled_time,0,1)
This technique is used in the sample models 'Lock animated' and 'Elevator animated'.

A bug in PIL caused non black texts to have a kind of outline around the characters in Animate(text=...).
This was especially visible with white texts on a dark background.
Code has been added to correct this behaviour.

Introduced a parameter visible for Animate and Animate.update. The method visible of animation
objects can be overridden. This is especially useful in dashboard like animations.

AnimateButton and AnimateSlider no longer have a layer parameter, as these UI elements are now always
on top of the Animate objects.

The animation parameters of run() are all removed. Now, a new animation_parameters method (in class Environment)
is used to set all parameters.
The function animation_speed has been phased out. It is now in animation_parameters.

Pythonista animation performance is increased by building up the image completely with PIL,
before putting it into a scene. This also results in higher quality images
(essentially the same as under tkinter).

On Pythonista, the animation size is now automatically set to the dimension of the screen.
This can be overridden with a call to animation_parameters.

In the animation, the Quit button has been renamed to Stop.

The color of the text in Animate(text=) is now set with textcolor0 and textcolor1 instead of fillcolor0 and
fillcolor1.

If a specified font in Animate cannot be found, the system now searches for calibri and next for arial fonts.

Bug fix: after a yield self.request call, the status of the component was still current, instead of scheduled.

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Animation on CPython platform is now slightly smoother, because there was a bug in the timing routine, which
caused that the animation was doomed to be slower than 30 fps.

The upper right hand corner now shows, optionally, the number of frames per second fps).
The run command has three new parameters, which control what is shown in the upper right hand corner, in case of animation:
show_fps : bool
if True, show the number of frames per second (default)|n|
if False, do not show the number of frames per second

show_animation_speed: bool
if True, show the animation speed (default)|n|
if False, do not show the animation speed

show_time: bool
if True, show the time (default)|n|
if False, do not show the time

The text of an AnimateButton is now set via function text(), which can be overridden.

The function str_or_function had been phased out, as this can be achieved now by overriding methods.

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Complete overhaul of the tkinter way objects are shown. Instead of deleting all canvas objects
for each animation tick, salabim now tries to minimize the number of create_image calls,
by using itemconfig and coords and reusing canvas elements, if possible and necessary.
The result is a much smoother animation, particularly at higher animation speeds.
The above doesn't, unfortunately, apply to Pythonista.

Now all of the following methods of the class Animate may be overridden:
def x(self,t=None)
def y(self,t=None)
def offsetx(self,t=None)
def offsety(self,t=None)
def angle(self,t=None)
def linewidth(self,t=None)
def linecolor(self,t=None)
def fillcolor(self,t=None)
def circle(self,t=None)
def line(self,t=None)
def polygon(self,t=None)
def rectangle(self,t=None)
def width(self,t=None)
def fontsize(self,t=None)
def text(self,t=None)
def anchor(self,t=None)
def image(self,t=None)
def layer(self,t=None)
, thus giving the possibility to use non linear movement, special effects, etc.

The distribution now also contains a script called salabim_install, which will install salabim
in the appropriate site-packages folder. Once installed, salabim can be used from whatever location!

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Animation interpolation can now be overridden (monkey patched) to allow for
non linear interpolation or advanced animation techniques.
For this make a new class based on Animation and redefine the necessary functions,
like x,y, angle.

As illustration of the possibilities, have a look at demo_override.py

Duck typing implemented for more Pythonic behaviour.