Virtual Touch
Mathematical functions are used to define various tangible physical properties (elasticity, friction, viscosity, and force fields) as well as geometry (curves, surfaces and solid objects), and visual appearance (3D colors and geometric textures) of the virtual objects.
A function-based extension of X3D and VRML which allows for defining complex geometry, appearance and haptic effects in virtual scenes by functions and common polygon-based models, with various object sizes, mutual penetrations, variable precision, and arbitrary location of the observer.
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