pypy compatibility

[atomizer]

Pypy is an alternative Python implementation with JIT.

Curretnly moderngl doesn't compile due to non-existence of following in pypy C API:

• 5.5.0:
  • PyException_HEAD macro
  • PyUnicode_Append
• next:
  • ob_base inside PyObject

[szabolcsdombi]

Thank you for the issue.
Most of the ob_base are used to access values that can be accessed with macros
I will replace those so next will be compatible with pypy

[szabolcsdombi]

I don't know a quick solution to get rid of PyException_HEAD for the 5.x compatibility

[szabolcsdombi]

please build moderngl 5.5 from the master
I have removed PyException_HEAD and PyUnicode_Append
I hope it works. I have not tested it yet.

540567f

[szabolcsdombi]

I am not able to build with pypy:

 error: Microsoft Visual C++ 14.1 is required. Get it with "Microsoft Visual C++ Build Tools": http://landinghub.visualstudio.com/visual-cpp-build-tools

Can you please test:

./pypy3.exe -m pip install https://github.com/moderngl/moderngl/archive/master.zip

[atomizer]

In GLMethods.cpp there's one mention of PyUnicde_Append left in (now unused) AddToLog. Removing the function makes it compile and work (tests pass).

[szabolcsdombi]

Super!

[atomizer]

I'm building it manually with setup.py build_ext --inplace since next still fails.

[szabolcsdombi]

I will fix next too. It will take more time due to a lot of ob_bases I guess

[szabolcsdombi]

I think it is done. Can you please check if both 5.x and next are building.

[szabolcsdombi]

https://travis-ci.org/moderngl/moderngl/jobs/506619895

[einarf]

Awesome stuff. This opens up for a lot of interesting experimentation. I wonder myself what kind of performance boost can be gained in some of my projects.

[atomizer]

Yes, it compiles. Creating a context using next causes instant crash. I'm not an expert on either engine's internals, but I think your direct object memory access/manipulation tricks (memsets, SLOT macro etc.) are CPython-only. It's really difficult (for me at least?) to find concrete info on what those differences are exactly, so I'm not quite sure how to debug this.

[szabolcsdombi]

I was not able to run pypy locally at all. I cannot get the msvc compiler installed for pypy. Probably the SLOT macro needs to be changes into something that supports PyObject_SetAttrString internally when needed.

[szabolcsdombi]

I will probably try to run pypy on Ubuntu soon.