Python Roundtable Friday

One person ported Python to the PS2, another to the GameCube

Memory Management
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Python allocates many tiny blocks

Cache issues important on consoles

Be very careful about fragmentation

Python has many different memory hooks -- check ceval2.c for allocations that happen all the time, eg. 2 allocs for each method call

Stackless Python can do lightweight threads (one person had 20,000 threads)

Where is the runtime only version of Python py-embed?
There's Pippy - Palm Python that's <= 256k with interpreter

Freeze takes bytecode and makes it statically loaded - can avoid module loading entirely.

Psyco is a JIT for Python

Pyrex uses Python runtime but can be compiled if you give variable declarations (with a new syntax)

"numeric" (used to be "numpy") is efficient on large vectors/matrices

Use map, apply, intrinsic data structures, otherwise up to 1000x slower on directly translated code

Avoid SWIG: bad for C++ (ok for C but slow/bloated), does a malloc for every call

PyOpenGL would be fast except for SWIG

Boost::Python problem is templates kill the compiler (GCC) on console

Just use Python's C API, avoid wrappers

One (nice) interface had about 50 3D engine+UI game engine entry points + like 2 for networking.  Others used SWIG and were huge.

There was 1 artist who was willing to write Python code

Design a very tight interface, otherwise designers writing Python code will cause trouble

Error checking is a bit annoying on a console where you have high turn-around.

Make a PC debugging client that connects to console's Python interpreter: inspect variables, reload scripts, etc.

Script development environment to improve productivity

Use PyUnit unit testing framework; replace compile button with unit test button.  Much easier to write unit tests in Python than C++.  Also console's C++ compilers suck (no/bad exception handling).

PyChecker - good for static checking, get the add-on

Designers want to iterate!  Can quickly determine what is fun.

Involve designers in interface(API) design

Pair program scripts with a designer and a programmer

Build an automated build script in Python

Someone's AI editor is in Python

"BuildBot" -- watches version control and rebuilds

"Scons" -- "make" replacement

"distutils" -- makes a Windows installer