1 ! (c) 2009 Joe Groff, see BSD license
2 USING: assocs kernel math.geometry.rect combinators accessors
3 math.vectors vectors sequences math math.points math.geometry
4 combinators.short-circuit arrays fry locals ;
7 TUPLE: quadtree { bounds rect } point value ll lr ul ur leaf? ;
9 : <quadtree> ( bounds -- quadtree )
14 : rect-ll ( rect -- point ) loc>> ;
15 : rect-lr ( rect -- point ) [ loc>> ] [ width ] bi v+x ;
16 : rect-ul ( rect -- point ) [ loc>> ] [ height ] bi v+y ;
17 : rect-ur ( rect -- point ) [ loc>> ] [ dim>> ] bi v+ ;
19 : rect-center ( rect -- point ) [ loc>> ] [ dim>> 0.5 v*n ] bi v+ ; inline
21 : (quadrant) ( pt node -- quadrant )
22 swap [ first 0.0 < ] [ second 0.0 < ] bi
23 [ [ ll>> ] [ lr>> ] if ]
24 [ [ ul>> ] [ ur>> ] if ] if ;
26 : quadrant ( pt node -- quadrant )
27 [ bounds>> rect-center v- ] keep (quadrant) ;
29 : descend ( pt node -- pt subnode )
30 [ drop ] [ quadrant ] 2bi ; inline
32 :: each-quadrant ( node quot -- )
36 node ur>> quot call ; inline
37 : map-quadrant ( node quot: ( child-node -- x ) -- array )
38 each-quadrant 4array ; inline
51 : child-dim ( rect -- dim/2 ) dim>> 0.5 v*n ; inline
52 : ll-bounds ( rect -- rect' )
53 [ loc>> ] [ child-dim ] bi <rect> ;
54 : lr-bounds ( rect -- rect' )
55 [ [ loc>> ] [ dim>> { 0.5 0.0 } v* ] bi v+ ] [ child-dim ] bi <rect> ;
56 : ul-bounds ( rect -- rect' )
57 [ [ loc>> ] [ dim>> { 0.0 0.5 } v* ] bi v+ ] [ child-dim ] bi <rect> ;
58 : ur-bounds ( rect -- rect' )
59 [ [ loc>> ] [ dim>> { 0.5 0.5 } v* ] bi v+ ] [ child-dim ] bi <rect> ;
61 : {quadrants} ( node -- quadrants )
62 { [ ll>> ] [ lr>> ] [ ul>> ] [ ur>> ] } cleave 4array ;
64 : add-subnodes ( node -- node )
66 [ ll-bounds <quadtree> >>ll ]
67 [ lr-bounds <quadtree> >>lr ]
68 [ ul-bounds <quadtree> >>ul ]
69 [ ur-bounds <quadtree> >>ur ]
73 : split-leaf ( value point leaf -- )
75 [ value>> ] [ point>> ] [ ] tri
76 [ node-insert ] [ node-insert ] bi ;
78 : leaf-replaceable? ( pt leaf -- ? ) point>> { [ nip not ] [ = ] } 2|| ;
79 : leaf-insert ( value point leaf -- )
80 2dup leaf-replaceable?
81 [ [ (>>point) ] [ (>>value) ] bi ]
84 : node-insert ( value point node -- )
87 : insert ( value point tree -- )
88 dup leaf?>> [ leaf-insert ] [ node-insert ] if ;
90 : leaf-at-point ( point leaf -- value/f ? )
91 tuck point>> = [ value>> t ] [ drop f f ] if ;
93 : node-at-point ( point node -- value/f ? )
96 : at-point ( point tree -- value/f ? )
97 dup leaf?>> [ leaf-at-point ] [ node-at-point ] if ;
99 : (node-in-rect*) ( values rect node -- values )
100 2dup bounds>> intersects? [ in-rect* ] [ 2drop ] if ;
101 : node-in-rect* ( values rect node -- values )
102 [ (node-in-rect*) ] with each-quadrant ;
104 : leaf-in-rect* ( values rect leaf -- values )
105 tuck { [ nip point>> ] [ point>> swap intersects? ] } 2&&
106 [ value>> over push ] [ drop ] if ;
108 : in-rect* ( values rect tree -- values )
109 dup leaf?>> [ leaf-in-rect* ] [ node-in-rect* ] if ;
111 : leaf-erase ( point leaf -- )
112 tuck point>> = [ f >>point f >>value ] when drop ;
114 : node-erase ( point node -- )
117 : erase ( point tree -- )
118 dup leaf?>> [ leaf-erase ] [ node-erase ] if ;
120 : (?leaf) ( quadrant -- {point,value}/f )
121 dup point>> [ swap value>> 2array ] [ drop f ] if* ;
122 : ?leaf ( quadrants -- {point,value}/f )
123 [ (?leaf) ] map sift dup length {
125 { 0 [ drop { f f } ] }
129 : collapseable? ( node -- {point,value}/f )
130 {quadrants} { [ [ leaf?>> ] all? ] [ ?leaf ] } 1&& ;
132 : remove-subnodes ( node -- leaf ) f >>ll f >>lr f >>ul f >>ur t >>leaf? ;
134 : collapse ( node {point,value} -- )
135 first2 [ >>point ] [ >>value ] bi* remove-subnodes drop ;
137 : node-prune ( node -- )
138 [ [ (prune) ] each-quadrant ] [ ] [ collapseable? ] tri
139 [ collapse ] [ drop ] if* ;
141 : (prune) ( tree -- )
142 dup leaf?>> [ drop ] [ node-prune ] if ;
144 : leaf>alist ( leaf -- alist )
145 dup point>> [ [ point>> ] [ value>> ] bi 2array 1array ] [ drop { } ] if ;
147 : node>alist ( node -- alist ) [ quadtree>alist ] map-quadrant concat ;
149 : quadtree>alist ( tree -- assoc )
150 dup leaf?>> [ leaf>alist ] [ node>alist ] if ;
152 : leaf-size ( leaf -- count )
153 point>> [ 1 ] [ 0 ] if ;
154 : node-size ( node -- count )
155 0 swap [ quadtree-size + ] each-quadrant ;
157 : quadtree-size ( tree -- count )
158 dup leaf?>> [ leaf-size ] [ node-size ] if ;
160 : leaf= ( a b -- ? ) [ [ point>> ] [ value>> ] bi 2array ] bi@ = ;
162 : node= ( a b -- ? ) [ {quadrants} ] bi@ = ;
164 : (tree=) ( a b -- ? ) dup leaf?>> [ leaf= ] [ node= ] if ;
167 2dup [ leaf?>> ] bi@ = [ (tree=) ] [ 2drop f ] if ;
171 : prune-quadtree ( tree -- tree ) [ (prune) ] keep ;
173 : in-rect ( tree rect -- values )
174 [ 16 <vector> ] 2dip in-rect* ;
176 M: quadtree equal? ( a b -- ? )
177 over quadtree? [ tree= ] [ 2drop f ] if ;
179 INSTANCE: quadtree assoc
181 M: quadtree at* ( key assoc -- value/f ? ) at-point ;
182 M: quadtree assoc-size ( assoc -- n ) quadtree-size ;
183 M: quadtree >alist ( assoc -- alist ) quadtree>alist ;
184 M: quadtree set-at ( value key assoc -- ) insert ;
185 M: quadtree delete-at ( key assoc -- ) erase ;
186 M: quadtree clear-assoc ( assoc -- )