cassowary¶ ↑

• github.com/sfeu/cassowary

Cassowary is an incremental constraint solving toolkit that efficiently solves systems of linear equalities and inequalities. Constraints may be either requirements or preferences. Client code specifies the constraints to be maintained, and the solver updates the constrained variables to have values that satisfy the constraints. Version 0.50 of the solving toolkit adds support for a one-way finite domain subsolver.

This project is concerned with offering a ruby interface for the original implementation of cassowary in C.

Please consider the current version as software that is still not finished.

Currently we can only say that “it works for us”…

We are using this constraint solver to generate graphical user interfaces with the Multimodal INTeraction framework (MINT).

See www.multi-access.de

require “rubygems” require “cassowary” solver = Cassowary::ClSimplexSolver.new

size = Cassowary::ClPoint.new()

solver.AddConstraint(ClLinearEquation.new(size.X,ClLinearExpression.new(10),Cassowary.ClsStrong)) solver.AddConstraint(ClLinearInequality.new(size.Y,CnGEQ,ClLinearExpression.new(0),Cassowary.ClsStrong))

Requires the libcassowary0 debian package that we packaged for Ubuntu LTS Lucid 10.04 and Precise 12.04. Just add our PPA by doing the following steps:

sudo add-apt-repository ppa:sfeu/ppa

sudo apt-get update

sudo apt-get install libcassowary0

or build yourself. The source code is available from the original site

www.cs.washington.edu/research/constraints/cassowary/

Copyright Cassowary Constraint Solver: Greg J. Badros, Alan Borning

sudo gem install cassowary

Licensed under the Lesser/Library GPL v2.1 or any version above.

Copyright © 2011-2012 Sebastian Feuerstack

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ‘Software’), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.