import type { FnU2 , FnU8 , Tuple } from "@thi.ng/api" ; import type { ReadonlyVec , Vec } from "@thi.ng/vectors" ; /**
 * Performs Liang-Barsky clipping of the line segment with endpoints
 * `a`, `b` against the clipping rect defined by `min` and `max`. The
 * optional `ca` and `cb` vectors can be given to store the result
 * (clipped points). If omitted creates new vectors. Returns a tuple of
 * `[ca, cb, a, b]`, where the latter two values represent the
 * normalized distances of the clipped points relative to original given
 * line segment. Returns `undefined` iff the line lies completely
 * outside the rect.
 *
 * -  https * -  https param a param b param min param max param ca param cb export const liangBarsky2 = ( a , b , min , max , ca = [ ] , cb = [ ] ) : [ Vec , Vec , number , number ] | undefined => { const res = liangBarsky2Raw ( a [ 0 ] , a [ 1 ] , b [ 0 ] , b [ 1 ] , min [ 0 ] , min [ 1 ] , max [ 0 ] , max [ 1 ] ) ; if ( ! res ) return ; ca [ 0 ] = res [ 0 ] ; ca [ 1 ] = res [ 1 ] ; cb [ 0 ] = res [ 2 ] ; cb [ 1 ] = res [ 3 ] ; return [ ca , cb , res [ 4 ] , res [ 5 ] ] ; } ; /**
 * Same as  liangBarsky2 but for non-vector arguments.
 *
 *  param ax param ay param bx param by param minx param miny param maxx param maxy export const liangBarsky2Raw = ( ax , ay , bx , by , minx , miny , maxx , maxy ) => { const dx = bx - ax ; const dy = by - ay ; let alpha = 0 ; let beta = 1 ; const clip = ( p , q ) => { if ( p < 0 ) { const r = q / p ; if ( r > beta ) { return false ; } if ( r > alpha ) { alpha = r ; } } else if ( p > 0 ) { const r = q / p ; if ( r < alpha ) { return false ; } if ( r < beta ) { beta = r ; } } else if ( q < 0 ) { return false ; } return true ; } ; return clip ( - dx , ax - minx ) && clip ( dx , maxx - ax ) && clip ( - dy , ay - miny ) && clip ( dy , maxy - ay ) ? [ alpha * dx + ax , alpha * dy + ay , beta * dx + ax , beta * dy + ay , alpha , beta , ] : undefined ; } ;