Method and program for determing intersection point of triangle with line segment

摘要

A coordinate system R is set in which P₀ is a coordinate origin, P₀P₁ conforms to a first U axis to have a unit length, P₀P₂ conforms to a second V axis to have a unit length, and P₀P₁×P₀P₂ is a unit vector conforming to a third N axis. A transforming matrix M that transforms an ordinary coordinate system into the coordinate system R and the u-, v- and n-coordinate values of the both ends of the line segment are calculated. It is determined whether or not the line segment intersects with the triangle, on the basis of the u-, v- and n-coordinate values. The u-, and v-coordinate values of the intersection point are calculated. It is determined whether or not the intersection point is positioned inside the triangle, on the basis of the u-, and v-coordinate values of the intersection point.