libcspp will be an Open Source and Free Software library for the solution of of classes of fluid flow where contour advective methods are relevant. The source code will be available under the Free Software Foundation's GPL license.

Contour advective methods are relevant to fluid flows where the vorticity (or potential vorticity) is conserved on fluid particles. If the vorticity can be represented as piecewise constant over the fluid, then the boundaries (commonly known as "contours") of constant vorticity regions are advected by the motion of the fluid. In principle, the vorticity field can be inverted to obtain the velocity field, which in turn can be used to advect the contours.

Bit of history.

The aim of this project is to provide a generic class library for contour advective flows. The library will be as flexible as possible, and will not require anything other than a standard C++ compiler and standard C++ library. The library is designed to handle the most basic use case of a single time step of a contour advection method:

• Provide discretised contours.
• Fit a curve through the contour nodes.
• Invert the vorticity field.
• Advect the contours.
• Redistribute the contour nodes.
• Perform contour surgery if required.
• Have the updated contours available for another time-step, and/or post-processing.