| 摘要 |
PURPOSE:To prevent the bordering edge or a surface in implicit-line/implicit- surface elimination from getting inside out. CONSTITUTION:A top point coordinate value of a surface inputted in a coordinate conversion means 1 is first converted into a prescribed coordinate system. Then a surface inside/outside discrimination means 2 introduces the normal vector of the surface from the top point coordinate value converted into the prescribed coordinate system and discriminates the inside/outside of the surface from the inner product with a line-of-sight vector. A drawing processing means 3 changes the mode setting of the Z-value comparison conditions for a straight line generator 4. It also controls the actuation of the straight line generator 4 to perform the apinting-out processing of the surface. The straight line generator 4 performs writing/non-writing processing to a Z buffer 5/frame buffer 6 in accordance with the set comparison condition mode. |
