PursuedPyBear, also known as ppb
, exists to be an educational
resource. Most obviously used to teach computer science, it can be a
useful tool for any topic that a simulation can be helpful.
At its core, ppb
provides a number of features that make it perfect
for video games. The GameEngine
itself provides a pluggable subsystem
architecture where adding new features is as simple as subclassing and
extending System
. Additionally, it contains a state stack of Scenes
simple containers that let you organize game scenes and UI screens in a
simple way.
The entire system uses an event system which is as extensible as the
rest of the system. Register new values to existing event types, and
even overwrite the defaults. Adding a new event type to the system is as
simple as firing an instance of your new event class with signal
.
Instead of a publisher system, the engine knows everything in its own scope
and only calls objects with appropriate callbacks. The most basic event is
Update
and your handlers should match the signature
on_update(self, update_event, signal)
.
Because ppb
started to be a game framework great for learning with,
the project has a few longterm goals:
Non-technical educators should feel comfortable after very little training. While some programming knowledge is required, the ability to think in objects and responses to events allows educators to only focus on their lessons.
A project built on ppb
should look like idiomatic Python. It also
should look like modern Python. As such, we often add new language
features as soon as they're available, letting a new user always know
ppb runs on the latest Python.
ppb
games are built out of instances of objects. Each object only has enough
information to respond to the event provided, which always includes the current
BaseScene
. Because ppb
doesn't have a master list of events, you can
provide new ones simply to add more granular control over your game.
Because ppb
strongly tries to be extensible and pluggable, each
hardware extension can provide its own hooks to ppb
, and you can
nearly seamlessly switch between various Python libraries.
One of the maintainers put it best:
If it’s not fun to use, we should redo it
ppb is about filing off the rough edges so that the joy of creation and discovery are both emphasized. A new user should be able to build their first game in a few hours, and continue exploring beyond that.
Install ppb in the standard method:
pip install ppb
ppb
provides a run
function that makes it simple to start single
screen games.
To make a very simple game, make a directory and add an image file
called ship.png
to it. Then add the following to a python file and
run it.
import ppb
from ppb.features.default_sprites import TargetSprite
class Ship(TargetSprite):
target = ppb.Vector(0, 40)
def setup(scene):
scene.add(Ship(pos=(0, -7)))
ppb.run(setup=setup)
ppb
is guaranteed compatible with Python 3.6 or later.
The fastest way to get involved is to check out the ongoing
discussions.
If you're already using ppb
feel free to report bugs, suggest
enhancements, or ask for new features.
If you want to contribute code, definitely read the relevant portions of Contributing.MD