A sculpture technique in which a three-dimensional form is manipulated in a soft material such as clay ? either modeling clay (Plasticine is a well-known brand) or ceramic clay ? or wax. The term also refers to the effect of light on a three-dimensional form. The three-dimensional quality of such a form is emphasized by means of light, shadow, and color. Reproducing the effect of light, shadow, and color in a drawing of such a form makes it seem more realistic. For example, see thumbnail to rightMasaccio (Italian, 1401