fix: prevent TKDPointTree.RawKNearest from unhiding hidden points

Author: Torwent

Source/simba.container_kdpointtree.pas

@@ -288,19 +288,27 @@ function TKDPointTree.Nearest(pt:TPoint; notEqual:Boolean=False): TPoint;
 
 
 function TKDPointTree.RawKNearest(pt:TPoint; k:Integer; notEqual:Boolean=False): TNodeRefArray;
-var i,c:Integer;
+var
+   i,c:Integer;
+   hidden: TIntegerArray;
 begin
   SetLength(Result, k);
   c := 0;
   while c < k do
   begin
      Result[c] := self.RawNearest(pt, notEqual);
      if Result[c] = nil then break;
-     Result[c]^.hidden := True;
+     if not Result[c]^.hidden then
+     begin
+       Result[c]^.hidden := True;
+       SetLength(hidden, Length(hidden)+1);
+       hidden[High(hidden)] := c;
+     end;
      inc(c);
   end;
 
-  for i:=0 to c-1 do Result[i]^.hidden := False;
+  for i:=0 to High(hidden) do
+    Result[hidden[i]]^.hidden := False;
   SetLength(Result, c);
 end;