PursuedPyBear
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.
A Game Engine
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)
.
Guiding Principles
Because ppb
started to be a game framework great for learning with, the project has a few longterm goals:
Education Friendly
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.
Idiomatic Python
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.
Object Oriented and Event Driven
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 Scene
. Because ppb
doesn't have a master list of events, you can provide new ones simply to add more granular control over your game.
Hardware Library Agnostic
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.
Fun
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.
Try it
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(position=(0, -7)))
ppb.run(setup=setup)
Depending on your operating system, you may need to install additional packages (see installation guide).
Compatibility
ppb
is guaranteed compatible with Python 3.6 or later.
Get Involved
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