i4h Catheter Navigation - Render DRR

Purpose

Render a single digitally reconstructed radiograph (DRR) frame. Works with a preprocessed CT cache from [[i4h-catheter-navigation-digital-twin]], a direct NIfTI/DICOM path, or the built-in synthetic phantom (no data required).

Base Code

ROOT="${I4H_WORKFLOWS:-$(git rev-parse --show-toplevel 2>/dev/null)}"
if [ ! -d "$ROOT/workflows/catheter_navigation" ]; then
  ROOT="${I4H_WORKFLOWS:-$HOME/i4h-workflows}"
  [ -d "$ROOT/workflows/catheter_navigation" ] || git clone https://github.com/isaac-for-healthcare/i4h-workflows "$ROOT"
fi
export I4H_WORKFLOWS="$ROOT"; cd "$ROOT"

Basics