Category Archives: PySoy

PySoy, a month after

A bit more than a month of SoC work has passed now, PySoy is alive and getting better day after day, and since some days you can even get a taste of it!
After the release of the GPLv3 our SVN repository has been opened to the public, read more on Arc’s blog.

Textured Pyramid

About the point of view of my application the project is proceeding well and we can show you a textured pyramid at last (as usual I have to thank Arc for the huge help 😉 )! 🙂

I’ve left my normal mapping experiments behind for a moment (after having discovered how to create correct object space normal maps in Blender with the “six colored lights” hack 😀 ), and I’m now working on the lighting system which will represent the base for every non trivial texturing technique.

Much more is yet to come, stay tuned!

A slighty smarter for PySoy r64

While working on PySoy I was really disappointed by the policy adopted by the script, anytime I launched it the result was a recompilation of *all* the sources, this was really annoying and slow.

Python transparent logo

What came after was just that I decided to hack it a bit and make it behave more like a standard build tool, that is to control the modification time of a source file in order to choose whether it is updated or need a fresh compilation.

The new policy for the script is very simple, but useful enough to save plenty of time.
It is aware of the following cases (thank you Arc for tips on how to deal with the last one):

  • a .c file is missing, pyrex should compile the .pyx file
  • a .pyx file is newer than the corresponding .c file, an update is needed
  • a .pxd file is newer than any .pyx file, a global recompile is needed

The last point is not optimal, of course, but it’s a lot simpler than specifying all the .pxd dependecies for any .pyx file, and, anyway, quite close to being optimal, because of the thick web of cross dependencies which actually exists in PySoy.

Here is the piece of code which performs the magic:

# Convert Pyrex sources to C if using Trunk
if version == 'Trunk' :
  import os
  from stat import *
  from Pyrex.Compiler import Main

  options = Main.CompilationOptions(defaults=Main.default_options, include_path=include_path)

  newestpxd = 0
  for dir in include_path:
    for pxdsource in os.listdir(dir):
      pxdsource_path = (os.path.join(dir, pxdsource))

      if os.path.isfile(pxdsource_path) and pxdsource.rsplit('.', 1)[1] == 'pxd':
        if os.stat(pxdsource_path)[ST_MTIME] > newestpxd:
          newestpxd = os.stat(pxdsource_path)[ST_MTIME]

  for pyxsource in pyrex_sources:
    compilation_needed = False

    if os.path.isfile(pyxsource.rsplit('.', 1)[0] + '.c'):
      ctime = os.stat(pyxsource.rsplit('.', 1)[0] + '.c')[ST_MTIME]
      ctime = 0

    if newestpxd > ctime:
      compilation_needed = True
    elif os.stat(pyxsource)[ST_MTIME] > ctime:
      compilation_needed = True

    if compilation_needed:
      Main.compile(pyxsource, options)

Well, actually Arc commited r65 too, simplifying the conditionals of the script even more, but this is another story. 🙂
Anyway, I hope to have made another little step into making the life of our team a bit simpler. 😉

My Summer of Code begins with PySoy r44

Summer of Code has started just today (even if currently it is only a “Spring of Code” 😀 ) but a little contribution of mine has already made his way inside the SVN repository of PySoy.

But let’s start from the beginning…
After having shown to Arc an early draft of an UML class diagram for the current code I decided to come back to work on some test code I had written in the afternoon.
It was just a classical spinning cube demo to actually compare PyOpenGL versus Pyrex speed, I don’t report the results here because they are quite identical, if I haven’t done any mistake it should be the absolute minimum complexity of the code which actually determined this result.
Anyway, even without this proof I firmly believe in the power and speed of Pyrex. 😉

Going back to my commit, my changes affected a small yet important area of the code, I think we will remember it in the future. 🙂

In src/windows-glx/


In include/gl.pxd:

# Constants
  ctypedef enum:
    # glPush/PopAttrib bits

In src/windows-glx/


Was it better before or now? 😉