amend 'foldRegion' function in MakeQuadFolder functor, by ensuring we don't visit only one child if item has coordinates in more than one child

This commit is contained in:
2025-01-20 10:46:09 +00:00
parent 6783dac9e0
commit 9c46e09ce4

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@@ -9,12 +9,50 @@ functor MakeQuadFolder(Fn: QUAD_FOLDER) =
struct struct
open QuadTreeType open QuadTreeType
fun visitTopLeft (iX, iY, iW, iH, qX, qY, qW, qH) =
let
val midX = qW div 2 + qX
val midY = qH div 2 + qY
in
iX <= midX andalso iY <= midY
end
fun visitTopRight (iX, iY, iW, iH, qX, qY, qW, qH) =
let
val midX = qW div 2 + qX
val midY = qH div 2 + qY
in
iX >= midX andalso iY <= midY
end
fun visitBottomLeft (iX, iY, iW, iH, qX, qY, qW, qH) =
let
val midX = qW div 2 + qX
val midY = qH div 2 + qY
val iFinishY = iY + iH
in
iX <= midX andalso iFinishY >= midY
end
fun visitBottomRight (iX, iY, iW, iH, qX, qY, qW, qH) =
let
val midX = qW div 2 + qX
val midY = qH div 2 + qY
val iFinishX = iX + iH
val iFinishY = iY + iH
in
iFinishX >= midX andalso iFinishY >= midY
end
fun foldVec (iX, iY, iW, iH, pos, elements, state, env) = fun foldVec (iX, iY, iW, iH, pos, elements, state, env) =
if pos = Vector.length elements then if pos = Vector.length elements then
state state
else else
let let
val {itemID, ...} = Vector.sub (elements, pos) val {itemID, ...} = Vector.sub (elements, pos)
val _ = print ("foldVec itemID: " ^ Int.toString itemID ^ "\n")
val state = Fn.fState (state, env, itemID) val state = Fn.fState (state, env, itemID)
in in
foldVec (iX, iY, iW, iH, pos + 1, elements, state, env) foldVec (iX, iY, iW, iH, pos + 1, elements, state, env)
@@ -42,32 +80,40 @@ struct
val halfW = quadW div 2 val halfW = quadW div 2
val halfH = quadH div 2 val halfH = quadH div 2
in
(case val midX = halfW + quadX
QuadTree.whichQuadrant val midY = halfH + quadY
(itemX, itemY, itemW, itemH, quadX, quadY, quadW, quadH)
of val iX = itemX
TOP_LEFT => val iY = itemY
val iW = itemW
val iH = itemH
val qX = quadX
val qY = quadY
val qW = quadW
val qH = quadH
val vtl = visitTopLeft (iX, iY, iW, iH, qX, qY, qW, qH)
val vtr = visitTopRight (iX, iY, iW, iH, qX, qY, qW, qH)
val vbl = visitBottomLeft (iX, iY, iW, iH, qX, qY, qW, qH)
val vbr = visitBottomRight (iX, iY, iW, iH, qX, qY, qW, qH)
val state =
if vtl then
foldRegion
(iX, iY, iW, iH, qX, qY, halfW, halfH, env, state, topLeft)
else
state
val state =
if vtr then
foldRegion foldRegion
( itemX ( itemX
, itemY , itemY
, itemW , itemW
, itemH , itemH
, quadX , midX
, quadY
, halfW
, halfH
, env
, state
, topLeft
)
| TOP_RIGHT =>
foldRegion
( itemX
, itemY
, itemW
, itemH
, quadX + halfW (* middleX *)
, quadY , quadY
, halfW , halfW
, halfH , halfH
@@ -75,35 +121,43 @@ struct
, state , state
, topRight , topRight
) )
| BOTTOM_LEFT => else
state
val state =
if vbl then
foldRegion foldRegion
( itemX ( itemX
, itemY , itemY
, itemW , itemW
, itemH , itemH
, quadX , quadX
, quadY + halfH (* middleY *) , midY
, halfW , halfW
, halfH , halfH
, env , env
, state , state
, bottomLeft , bottomLeft
) )
| BOTTOM_RIGHT => else
state
in
if vbr then
foldRegion foldRegion
( itemX ( itemX
, itemY , itemY
, itemW , itemW
, itemH , itemH
, quadX + halfW (* middleX *) , midX
, quadY + halfH (* middleY *) , midY
, halfW , halfW
, halfH , halfH
, env , env
, state , state
, bottomRight , bottomRight
) )
| PARENT_QUADRANT => state) else
state
end end
| LEAF elements => | LEAF elements =>
foldVec (itemX, itemY, itemW, itemH, 0, elements, state, env) foldVec (itemX, itemY, itemW, itemH, 0, elements, state, env)