Abstract: A method fills a polygon and then draws edge lines while inhibiting renewal of only depth data in a depth buffer. Thereafter, a method fills the polygon while inhibiting renewal of only color data in a color buffer. The filling and drawing are performed by applying hidden surface removing processings based upon depth buffer algorithm.

Abstract: A polygon division method, and polygon division apparatus are disclosed for dividing polygons according to a basic judgement as to whether each apex of the polygon is concave or convex. According to the claimed method, and what is carried out by the claimed apparatus, each apex of a polygon is judged as to whether it is concave or convex. The total number of apexes of the polygon is stored. A first convex apex is selected, whereupon a judgement is made as to whether another apex is present in the interior of a triangle that is formed by two sides which unite at the selected convex apex and a line segment that interconnects the ends of such sides. If no other apex is presence in the interior of such triangle, the triangle is cut from the polygon. Otherwise, a different convex apex is chosen. Further, the method and apparatus could include selection of convex apexes based upon whether the convex apexes overlap other apexes.

Abstract: A method for drawing a surface model performs modelling for plural primitive surface models, each primitive surface model being a part of the surface model, and applies drawing priority to each primitive surface model. Then, the method draws the primitive surface model with hidden surface removal based on depth values when the primitive surface model has the same drawing priority as the drawing priority of another primitive surface model, and draws the primitive surface model without hidden surface removal when the primitive surface model has a higher drawing priority.

Abstract: A method for displaying a translucent object on a display screen includes a step of displaying a translucent object by providing a diffused transmitted light component instead of a diffused reflection light component and a specular reflection light component as are necessary for displaying an object as an opaque object. A method for displaying a translucent object on a screen also includes a step of judging whether or not an object to be displayed is to be displayed as a translucent object based upon a relation of a viewpoint and a light source to the object to be displayed.

Abstract: A distance measurement apparatus receives pseudo noise reflected from a target object. The apparatus then obtains a cross-correlation value from cross-correlation of the received pseudo noise with pseudo noise which has been convoluted with expected measurement values. The apparatus measures a distance to the target object based upon the cross-correlation value. Also, a relative position measurement apparatus measures distances to an operator from plural points on the apparatus and then measures a relative position of the operator with respect to the apparatus based upon the plural distances.

Abstract: Discrimination of the condition of polygons is carried out by performing coordinate transformation from a view reference coordinate to a light source coordinate for each polygon. Then shadowing is carried out for every pixel of the polygon which is to be partially shaded. Also when multiple light sources exist, detection of the polygon is carried out by performing a coordinate transformation to each light source coordinate system for each polygon to be subjected to a shadowing operation. The detection includes detecting whether or not each polygon is the most light source side from among several polygons, thereafter intensity for display of each pixel is obtained based upon every detection result corresponding to each light source coordinate system.