Proposal: add a Python GUI pre/post-processing tool for VPSC8

[ZhiyangNi]

Summary

We have developed VPSC-GUI, an open-source, Python/Tkinter-based graphical user interface for VPSC8. It is designed to streamline the pre-processing, execution, and post-processing workflow without modifying the original Fortran solver.

This tool has recently been documented and peer-reviewed in SoftwareX:

VPSC-GUI: A Python graphical pre- and post-processing environment for the Visco-Plastic Self-Consistent code
SoftwareX, 2026. (DOI/Version v1.0.1)

We would like to propose integrating/linking this graphical tool into the main repository (e.g., under tools/vpsc_gui/ or referencing it in the documentation) to help new users and students lower the operational barrier to VPSC modeling.

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Key Features

• Structured Pre-Processing:
  • Interactive preview and editing for VPSC8.IN, single-crystal .sx files (FCC, BCC, HCP; Voce hardening and raw text fallback), and process/loading files.
  • Multi-phase aware handling (support for multi-phase .sx, texture files, and phase-resolved output parsing).
• Boundary Condition Visualizer:
  • Real-time 2D grid/deformation visualization for imposed velocity gradient tensor L and Cauchy stress constraints to catch input errors before launching.
• Isolated Execution & Traceability:
  • Automated generation of a clean, isolated Fortran-compatible run directory without altering any core Fortran source code.
• Integrated Post-Processing & Visualization:
  • Direct plotting and high-resolution export for standard VPSC output files, including:
    • STR_STR.OUT (Stress-strain response)
    • ACT_PH*.OUT (Slip/twinning activity)
    • TEX_PH*.OUT (Pole figures and Inverse pole figures using Lambert equal-area projection)
    • LANKFORD.OUT (Lankford coefficients / R-value anisotropy and directional Young's moduli)
    • PCYS.OUT (Polycrystal yield loci)

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Proposed Repository Structure

We can contribute this package as a standalone module placed under:

tools/vpsc_gui/
├── vpsc_gui/         # Core Python GUI source code
├── examples/         # Benchmark cases (FCC rolling, HCP compression, BCC/FCC tension)
├── README.md         # Quick start guide and user documentation
└── requirements.txt  # Lightweight dependencies (tkinter, numpy, matplotlib)