Geometric Tests - 3D Math Primer for Graphics and Game Development - page 743

c a s e 2 : / / i n t e r s e c t w i t h xy p l a n e

{

f l o a t x = r a y O r g . x + r a y D e l t a . x ∗ t ;

i f ( x < min . x | | x > max . x ) r e t u r n k N o I n t e r s e c t i o n ;

f l o a t y = r a y O r g . y + r a y D e l t a . y ∗ t ;

i f ( y < min . y | | y > max . y ) r e t u r n k N o I n t e r s e c t i o n ;

i f ( r e t u r n N o r m a l ! = NULL ) {

r e t u r n N o r m a l −> x = 0 . 0 f ;

r e t u r n N o r m a l −> y = 0 . 0 f ;

r e t u r n N o r m a l −> z = zn ;

}

}

br ea k ;

}

/ / R e t u r n p a r a m e t r i c p o i n t o f i n t e r s e c t i o n

r e t u r n t ;

}

Listing A.6
Ray-box intersection