Lass - Library of Assembled Shared Sources

Tom De Muer tom@cocamware.com
Bram de Greve bram@cocamware.com

Lass is an open source C++ library written by Tom De Muer and Bram de Greve to
help the authors writing better code. It includes an interfacing library to
Python, templated geometric primitives and spatial subdivision schemes, several
design patterns and other utilities the authors use in their day-to-day
codings.

License

Lass is dual licensed under CPAL-1.0 and GPL-2.0-or-later, see
COPYING file.

Documentation

• Reference documentation (doxygen)

Requirements

• Python >= 3.9
• CMake >= 3.18

Building

Lass uses the CMake build system.

Lass specific options

• Lass_PYTHON_VERSION (STRING): If you want a specific version of
  Python, set this variable before running CMake for the first time
  in an empty build directory. It accepts both <major>.<minor> and exact
  <major>.<minor>.<patch> versions.
• Python_EXECUTABLE (FILEPATH): If CMake cannot find the Python
  requested, you need to help it by specifying the full path to Python
  executable. Set this variable before running CMake for the first time
  in an empty build directory.
• BUILD_SIMD_ALIGNED (BOOL): Align some data structures on 16-byte
  boundaries for better SSE2 alignment. But this does not necessarily
  improve performance! OFF by default.
• BUILD_USING_PRECOMPILED_HEADERS (BOOL): Requires Microsoft Visual
  C++ compiler. ON by default, if this is the case.
• BUILD_WITHOUT_ITERATOR_DEBUGGING: (BOOL): Requires Microsoft Visual
  C++ compiler. If set, it adds /D_HAS_ITERATOR_DEBUGGING=0 as compiler
  option. It dramatically improves performance of a Debug build, but it
  is not ABI compatibily with binaries that don't use this setting. So, it is
  OFF by default.
• Lass_WITH_STUBGEN (BOOL): Generate Python *.pyi stubs and add
  lass_stubgen and LassStubgen.cmake to the installation.
  ON if Python version >= 3.10 and libclang(.dll|.so) can be found.
• Lass_LIBCLANG_LIBRARY(FILEPATH): Override the full path to the
  libclang library to be used to generate the Python *.pyi stubs.
• Lass_LIBCLANG_SYSTEM_INCLUDE_DIR(PATH): Override the Clang system
  include directory to be used to generate the Python *.pyi stubs. This typically
  is "${Lass_LIBCLANG_LIBRARY}/../lib/clang/<version>/include".

Generic options

• BUILD_SHARED_LIBS (BOOL): Build Lass as shared libraries instead
  of static libraries. ON by default.
• BUILD_TESTING (BOOL): ON by default.

Tested platforms

Lass is build and tested on following combinations of platforms and tools.

Where possible, we rely on stock versions of the tools as provided by the
platform's package manager. Windows being the exception.

[1] armv7l support tested on Raspberry Pi 4 (ARM Cortex-A72, 32-bit Raspbian Bullseye,
CXXFLAGS=-mcpu=cortex-a72 -mfpu=neon-fp-armv8) and BeagleBoneBlack (ARM Cortex-A8,
Debian Bullseye, CXXFLAGS=-mcpu=cortex-a8 -mfpu=neon). On RPi4, the Clang build requires
C++17 or newer.

[2] aarch64 support tested on Raspberry Pi 4 (ARM Cortex-A72, 64-bit Raspbian Bullseye,
CXXFLAGS=-mcpu=cortex-a72). Just like x64, aarch64 will assume 48-bit pointer addresses
in TaggedPtr. volatile atomics are not supported anymore, use std::atomic.