Three-dimensional modeling apparatus and method utilizing the extraction of topological data, as from two-dimensional drawings

A three-dimensional drawing forming method comprising the steps of:

• recognizing a closed region of two-dimensional drawings, said recognizing step performing recognizing with regard to two-dimensional drawings of a first direction and those of a second direction, respectively;
• adding information in a depth direction to the closed region recognized in the recognizing step, said adding step performing addition with regard to two-dimensional drawings of a first direction and those of a second direction, respectively;
• forming a plurality of sectional information in accordance with the information in the depth direction added to the recognized closed region;
• and
• forming a three-dimensional drawing from the plurality of sectional information.

A three-dimensional drawing apparatus comprising:

• storage means for storing two-dimensional drawings of a three-dimensional drawing expressed from three directions;
• recognizing means for recognizing a closed region of the two-dimensional drawings, said recognizing means performing recognizing with regard to two-dimensional drawings of a first direction and those of a second direction, respectively;
• addition means for adding information in a depth direction to the closed region recognized by said recognizing means, said addition means performing addition with regard to two-dimensional drawings of a first direction and those of a second direction, respectively;
• section forming means for forming section information of at least two directions in accordance with the information in the depth direction added to the recognized closed region;
• and
• drawing forming means for forming a three-dimensional drawing in accordance with the formed section information.