Interactive shading protractor in GeoGebra for Mazria's cylindrical projection

Shading protractor, as developed by Edward Mazria, recreated as an interactive graph in GeoGebra.

To use the protractor, one first needs to create a solar path chart for a given location, for example using the online tool available at http://solardat.uoregon.edu/SunChartProgram.html. This solar path chart has to be inserted as a background image in the shading protractor file, and the upper left corner ULC and the center P (labeled as 0 degrees) aligned with the solar path chart.

The protractor serves to illustrate shading masks for an overhang with side fins for a window with given orientation. Their defining points can be moved around freely in GeoGebra to observe how the shading mask changes accordingly.