/unmaintained/jamshred/oint/oint.factor
http://github.com/abeaumont/factor · Factor · 73 lines · 47 code · 20 blank · 6 comment · 0 complexity · ebed444cc70fd2cc11652abf030f5d9c MD5 · raw file
- ! Copyright (C) 2007, 2008 Alex Chapman
- ! See http://factorcode.org/license.txt for BSD license.
- USING: accessors arrays kernel locals math math.constants math.functions math.matrices math.vectors math.quaternions random sequences ;
- IN: jamshred.oint
- ! An oint is a point with three linearly independent unit vectors
- ! given relative to that point. In jamshred a player's location and
- ! direction are given by the player's oint. Similarly, a tunnel
- ! segment's location and orientation are given by an oint.
- TUPLE: oint location forward up left ;
- C: <oint> oint
- : rotation-quaternion ( theta axis -- quaternion )
- swap 2 / dup cos swap sin rot n*v first3 rect> [ rect> ] dip 2array ;
- : rotate-vector ( q qrecip v -- v )
- v>q swap q* q* q>v ;
- : rotate-oint ( oint theta axis -- )
- rotation-quaternion dup qrecip pick
- [ forward>> rotate-vector >>forward ]
- [ up>> rotate-vector >>up ]
- [ left>> rotate-vector >>left ] 3tri drop ;
- : left-pivot ( oint theta -- )
- over left>> rotate-oint ;
- : up-pivot ( oint theta -- )
- over up>> rotate-oint ;
- : forward-pivot ( oint theta -- )
- over forward>> rotate-oint ;
- : random-float+- ( n -- m )
- #! find a random float between -n/2 and n/2
- dup 10000 * >integer random 10000 / swap 2 / - ;
- : random-turn ( oint theta -- )
- 2 / 2dup random-float+- left-pivot random-float+- up-pivot ;
- : location+ ( v oint -- )
- [ location>> v+ ] [ (>>location) ] bi ;
- : go-forward ( distance oint -- )
- [ forward>> n*v ] [ location+ ] bi ;
- : distance-vector ( oint oint -- vector )
- [ location>> ] bi@ swap v- ;
- : distance ( oint oint -- distance )
- distance-vector norm ;
- : scalar-projection ( v1 v2 -- n )
- #! the scalar projection of v1 onto v2
- [ v. ] [ norm ] bi / ;
- : proj-perp ( u v -- w )
- dupd proj v- ;
- : perpendicular-distance ( oint oint -- distance )
- [ distance-vector ] keep 2dup left>> scalar-projection abs
- -rot up>> scalar-projection abs + ;
- :: reflect ( v n -- v' )
- #! bounce v on a surface with normal n
- v v n v. n n v. / 2 * n n*v v- ;
- : half-way ( p1 p2 -- p3 )
- over v- 2 v/n v+ ;
- : half-way-between-oints ( o1 o2 -- p )
- [ location>> ] bi@ half-way ;