"GRAPE For Web" is a parametric shape grammar interpreter. The implementation is based on maximal lines and supports emergence (Stiny, 1980). Parametric rules are supported up to U23 x V03 and emergent shapes are recognized up to U13.

"GRAPE For Web" is a webinterface for the GRAPE library. The application makes use of the HTML5 canvas element and hence requires a browser that supports it.


Classic rules

Rules that are matched using similarity transformations (rotations, translations, reflections, scalings).

Parametric Rules

Rules that are matched based on their topology and a variable amount of parametric constraints.

3D rules

3D rules support lines, faces, lines and labels. Views are rendered using HTML5 and WebGL. 3D content will be disabled if your browser does not support WebGL, either natively or through a plugin.


Since GRAPE models shapes using maximal lines emergence is supported.


Labels are rendered as circles or spheres with inscribed values.

DXF Export

Export the current drawing or the entire derivation layed out in a table.

Rule Editor

A visual rule editor is available. For more information about its capabilities please refer to the documentation. A login is required to use the editor.
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