Interoperable interactive geometry for Europe
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This platform is brought to you by the intergeo project, funded under the eContent Plus programme of the European commission and by partners


A real number from 0 to 1. For those elements with an interior, such as polygons, this style indicates how opaque they have to be painted with their fill color. The default value is system dependent (for instance, 1 in WIRIS, a small number in GeoGebra).

This style was named "fill_opacity" in a previous version of the File Format.


  1. styles example: source JSXGraph