Skip to content

PYTHON_MODULE_STATUS.md

Latest commit

 

History

History
178 lines (133 loc) · 4.88 KB

PYTHON_MODULE_STATUS.md

File metadata and controls

178 lines (133 loc) · 4.88 KB

FluidX3D Python Module - Development Status

✅ Phase 1: Initial Setup (COMPLETED)

What's Working

  1. Python Module Infrastructure

    • ✅ setup.py for building the extension
    • ✅ pyproject.toml for modern Python packaging
    • ✅ pybind11 integration
    • ✅ Successful compilation with MSVC

  2. Argument Validation

    • ✅ Validates velocity set arguments (--D2Q9, --D3Q15, --D3Q19, --D3Q27)
    • ✅ Proper error handling (throws Python exceptions instead of exit())
    • ✅ Error messages returned to Python caller
    • ✅ No console output when used as module

  3. Module Interface

    import fluidx3d

# Function-level API
fluidx3d.validate_args(['--D3Q27'])

# Class-based API
validator = fluidx3d.ArgumentValidator()
validator.validate_args(['--D3Q27'])
validator.get_version()

Build Instructions

# Windows (from FluidX3D-2.16 directory)
python setup.py build_ext --inplace
copy src\fluidx3d.cp314-win_amd64.pyd fluidx3d.pyd

# Test
python test_module.py

Test Results

============================================================
FluidX3D Python Module Test
============================================================
Version: 2.16.0-python

Test 1: Validating with no arguments...
  ✅ SUCCESS: Caught expected error: Must pick one of --D3Q15 --D3Q19 --D3Q27 or --D2Q9

Test 2: Validating with valid arguments (--D3Q27)...
  ✅ SUCCESS: Arguments validated successfully!

Test 3: Validating with multiple velocity sets...
  ✅ SUCCESS: Caught expected error: Can only pick one velocity set (...)

Test 4: Using ArgumentValidator class...
  ✅ SUCCESS: Arguments validated!
============================================================

🚧 Phase 2: Full Integration (TODO)

Next Steps

  1. Expand Argument Parsing

    • Integrate full cxxopts argument parsing
    • Support all FluidX3D CLI arguments
    • Create Python-friendly parameter structure

  2. Core Simulation Functionality

    • Expose LBM class to Python
    • Implement simulation initialization
    • Add run() method for stepping simulation
    • Support different velocity sets at runtime

  3. Data Exchange

    • Return velocity fields as NumPy arrays
    • Return pressure fields as NumPy arrays
    • Extract force/drag coefficients
    • Zero-copy access where possible

  4. Graphics Integration

    • Optional graphics rendering
    • Frame export to files
    • Video generation support

  5. Testing & Validation

    • Compare results with standalone .exe
    • Performance benchmarking
    • Memory usage profiling

📋 Design Decisions

Why Start Minimal?

We began with a minimal standalone module (just argument validation) to:

  • ✅ Verify pybind11 integration works
  • ✅ Test build system
  • ✅ Confirm error handling approach
  • ✅ Establish development workflow

Next Integration Strategy

Rather than linking all of FluidX3D's C++ code at once (which caused 30+ linker errors), we'll:

  1. Add components incrementally
  2. Create thin wrappers for external dependencies
  3. Mock/stub GUI components (not needed in Python)
  4. Focus on compute-only functionality first

PyPI Distribution Plans

Once core functionality works:

  • Create wheel distributions (.whl)
  • Support Windows, Linux, macOS
  • Provide pre-built binaries for common platforms
  • Publish to PyPI for pip install fluidx3d

🔧 Technical Notes

Compiler Settings

  • C++17 standard
  • MSVC optimization: /O2 /fp:fast
  • Link-time code generation (LTCG)

Python Compatibility

  • Tested: Python 3.14.0
  • Target: Python 3.11.14+
  • Module naming: fluidx3d.cp3XX-win_amd64.pyd

Dependencies

  • pybind11 >= 2.6.0
  • numpy >= 1.19.0 (for future data exchange)
  • OpenCL (for computation, will add later)

📝 Best Practices Followed

  1. ✅ Modern Python packaging (pyproject.toml + setup.py)
  2. ✅ Exception handling instead of exit() calls
  3. ✅ Incremental development (working minimal version first)
  4. ✅ Test-driven (test script validates functionality)
  5. ✅ Cross-version support (3.11+)

🎯 Success Criteria

Phase 1 (COMPLETED) ✅

  • Module compiles successfully
  • Module imports in Python
  • Argument validation works
  • Errors properly returned to Python
  • No console pollution

Phase 2 (IN PROGRESS)

  • Run actual LBM simulation from Python
  • Extract simulation results
  • Match performance of standalone .exe
  • Support all CLI arguments

Phase 3 (PLANNED)

  • NumPy array integration
  • Multiple simulation management
  • Pythonic API design
  • PyPI distribution

📚 Resources

Last Updated: 2025-11-04
Status: Phase 1 Complete, Phase 2 Planning