#116 So you want Python in a 3D graphics engine?

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Brian #1: Inside python dict — an explorable explanation

• Interactive tutorial on dictionaries
  • Searching efficiently in a list
  • Why are hash tables called has tables?
  • Putting it all together to make an “almost”-Python-dict
  • How Python dict really works internally
• Yes this is a super deep dive, but wow it’s cool.
• Tons of the code is runnable right there in the web page, including moving visual representations, highlighted code with current line of code highlighted.
• Some examples allow you to edit values and play with stuff.

Michael #2: Embed Python in Unreal Engine 4

• You may notice a theme throughout my set of picks on this episode
• Games built on Unreal Engine 4 include
  • Fortnite: Save the World
  • Gears of War 4
  • Marvel vs. Capcom: Infinite
  • Moto Racer 4
  • System Shock (remake)
• Plugin embedding a whole Python VM in Unreal Engine 4 (both the editor and runtime).
• This means you can use the plugin to write other plugins, to automate tasks, to write unit tests and to implement gameplay elements.
• Here is an example usage. It’s a really nice overview and tutorial for the editor.
• For game elements, check out this section.

Brian #3: Redirecting stdout with contextlib

• When I want to test the stdout output of some code, that’s easy, I grab the capsys fixture from pytest.
• But what if you want to grab the stdout of a method NOT while testing?
• Enter [contextlib.redirect_stdout(new_target)](https://docs.python.org/3/library/contextlib.html#contextlib.redirect_stdout)
• so cool. And very easy to read.
• ex:

    f = io.StringIO()
    with redirect_stdout(f):
        help(pow)
    s = f.getvalue()

• also a version for stderr

Michael #4: Panda3D

• via Kolja Lubitz
• Panda3D is an open-source, completely free-to-use engine for realtime 3D games, visualizations, simulations, experiments
• Not just games, could be science as well!
• The full power of the graphics card is exposed through an easy-to-use API. Panda3D combines the speed of C++ with the ease of use of Python to give you a fast rate of development without sacrificing on performance.
• Features:
  • Platform Portability
  • Flexible Asset Handling: Panda3D includes command-line tools for processing and optimizing source assets, allowing you to automate and script your content production pipeline to fit your exact needs.
  • Library Bindings: Panda3D comes with out-of-the-box support for many popular third-party libraries, such as the Bullet physics engine, Assimp model loader, OpenAL
  • Performance Profiling: Panda3D includes pstats — an over-the-network profiling system designed to help you understand where every single millisecond of your frame time goes.

Brian #5: Why PyPI Doesn't Know Your Projects Dependencies

• Some questions you may have asked: > How can I produce a dependency graph for Python packages? > Why doesn’t PyPI show a project’s dependencies on it’s project page? > How can I get a project’s dependencies without downloading the package? > Can I search PyPI and filter out projects that have a certain dependency?
• If everything is in requirements.txt, you just might be able to, but…
• setup.py is dynamic. You gotta run it to see what’s needed.
• Dependencies might be environment specific. Windows vs Linux vs Mac, as an example.
• Nothing stopping someone from putting random.choice() for dependencies in a setup.py file. But that would be kinda evil. But could be done. (Listener homework?)
• The wheel format is way more predictable because it limits some of this freedom. wheels don’t get run when they install, they really just get unpacked.
• More info on wheels: Kind of a tangent, but what why not:
  • From: https://pythonwheels.com
  • “Advantages of wheels
    • Faster installation for pure Python and native C extension packages.
    • Avoids arbitrary code execution for installation. (Avoids setup.py)
    • Installation of a C extension does not require a compiler on Linux, Windows or macOS.
    • Allows better caching for testing and continuous integration.
    • Creates .pyc files as part of installation to ensure they match the Python interpreter used.
    • More consistent installs across platforms and machines.”

Michael #6: PyGame series

• via Matthew Ward
• Learn how to program in Python by building a simple dice game
• Build a game framework with Python using the PyGame module
• How to add a player to your Python game
• Using PyGame to move your game character around
• What's a hero without a villain? How to add one to your Python game
• Put platforms in a Python game with PyGame
• Also: Shout out to Mission Python book: Code a Space Adventure Game!

Extras:

Joke (maybe, Brain feel free to pick another one):

• via @realpython
• Why do Pythons live on land? They are above C-level!