OpenCSG 1.8.1

This is a bugfix release. It makes the recently added GLSL vertex shader call also work with OpenGL versions 2.0 and 2.1.
Before, an internal fragment shader had an OpenGL 3.0 requirement, and so rendering failed with older OpenGL versions.

Also, a change has been reverted that solved some z-artifacts with Nouveau on Linux, but that triggered a different kind of rendering error on MacOS X.

Finally, an error in the CMake configuration has been resolved.

OpenCSG 1.8.0

The new release contains a number of changes to avoid z-artifacts. Most importantly, it is now possible to provide a GLSL vertex shader to OpenCSG. If a compatible shader is also used in the calling application to process the geometry, this can avoid z-artifacts that happened with older versions.

The new release also provides minor performance improvements in the SCS algorithm, by reducing the number of rendered primitives using shorter permutation embedding sequences. And for building on non-Windows platforms, it has switched from the old qmake-based makefiles to CMake.

OpenCSG 1.7.0

Rendering improvements for the case that the camera is in the interior of the CSG object. With previous releases, this case resulted in rendering errors. Now, this case is, depending on parametrization, handled correctly.

OpenCSG 1.6.0

Uses Glad instead of GLEW for OpenGL extension loading. The dependency on GLX on Linux no longer exists, and it should be possible to use OpenCSG on platforms that come with alternatives to GLX, such as EGL.

OpenCSG 1.5.1

Fix for a compilation error introduced with 1.5.0, which particularly occured with recent versions of gcc.

OpenCSG 1.5.0

With OpenCSG 1.5.0, the license is changed from GPL version 2 only to GPL version 2 or newer.

The release also contains a small API cleanup. The obsolete render() function taking three arguments has been removed. All rendering options must now be set via the setOption() function.