1. An image creating apparatus, comprising: an input section that inputs various information; a display section that displays the various information; a material data storage section that stores material data for creating computer graphics; a text string/material correspondence table in which the material data is associated with a set of material names for the material data; a hierarchical structural description that describes a feature of the material data in a hierarchical structure; a search section that, when the feature is input from the input section, searches for material data corresponding to the feature using the hierarchical structural description; a registration section that stores the searched material data in the material data storage section and registers the searched material data and a material name of the material data with the text string/material correspondence table; and a text string/CG conversion processing section that, when a text to designate the material name is input to an input screen, refers to the text string/material correspondence table, searches for a material name, with which the input text partially matches, acquires material data corresponding to the material name, and creates the computer graphics using the acquired material data.