IBRT

IBRT is the Interactive BRL-CAD Ray Tracer. This repository now holds our application and our OSPRay plugins, not a vendored OSPRay source tree.

What Lives Here

• apps/IBRT The Qt desktop viewer, render worker, and test suite.
• plugins/brl_cad The BRL-CAD OSPRay plugin built as ospray_module_brl_cad.
• docs Project-specific build notes, layout notes, and performance plans.

Dependency Model

OSPRay, Qt, Embree, rkcommon, ISPCRT, TBB, and related runtime dependencies come from an external bext install tree supplied at CMake configure time with BEXT_INSTALL_DIR.

This repo does not vendor or build OSPRay itself anymore.

Build

You need:

• a bext install tree, typically something like <bext>/.build/install
• a BRL-CAD install prefix
• CMake 3.20+
• a working C++ toolchain

Example:

cmake -S . -B build/local \
  -DBEXT_INSTALL_DIR=/path/to/bext/.build/install \
  -DBRLCAD_PREFIX=/path/to/brlcad/install
cmake --build build/local
ctest --test-dir build/local --output-on-failure

If Qt is not part of the supplied bext install, extend CMAKE_PREFIX_PATH when configuring.

More detail lives in docs/building.md.

Runtime Notes

• IBRT and IBRTRenderWorker use OSPRay from the supplied bext install.
• The BRL-CAD plugin is built in this repo and deployed into the local runtime output for the app, worker, and tests.
• Demo BRL-CAD databases are loaded from BRLCAD_PREFIX/share/db and copied into local viewer runtimes when available.

Repository Docs

• Building
• Repo Layout
• Performance Notes