private bool MoveStickyBoxes(HashSet <StickyBox> visited, StickyBox box, IntVec dir)
{
bool firstBox = visited.Count == 0;
IntVec ortho = new IntVec(-dir.Y, dir.X);
// all connected sticky boxes, in row/column of move direction
List <StickyBox> group = new List <StickyBox>();
// all boxes to the side of row/column, connected to group
List <StickyBox> branches = new List <StickyBox>();
// move backwards
var nextBox = CurrentState.EntityAt <StickyBox>(box.Pos - dir);
while (nextBox != null)
{
var left = CurrentState.EntityAt <StickyBox>(nextBox.Pos - ortho);
if (left != null)
{
branches.Add(left);
}
var right = CurrentState.EntityAt <StickyBox>(nextBox.Pos + ortho);
if (right != null)
{
branches.Add(right);
}
if (!visited.Add(nextBox))
{
break;
}
group.Add(nextBox);
nextBox = CurrentState.EntityAt <StickyBox>(nextBox.Pos - dir);
}
// move forwards
nextBox = CurrentState.EntityAt <StickyBox>(box.Pos);
while (nextBox != null)
{
var left = CurrentState.EntityAt <StickyBox>(nextBox.Pos - ortho);
if (left != null)
{
branches.Add(left);
}
var right = CurrentState.EntityAt <StickyBox>(nextBox.Pos + ortho);
if (right != null)
{
branches.Add(right);
}
if (!visited.Add(nextBox))
{
break;
}
group.Add(nextBox);
nextBox = CurrentState.EntityAt <StickyBox>(nextBox.Pos + dir);
}
// can only move 1 wide groups!
//if (firstBox && group.Count > 1)
// return false;
StickyBox farthest = group[group.Count - 1];
if (!CanMoveEntity(farthest, dir))
{
return(false);
}
// move all boxes in group
foreach (var s in group)
{
s.Pos += dir;
}
// execute all branches
foreach (var s in branches)
{
// avoid duplicate movement
if (visited.Contains(s))
{
continue;
}
MoveStickyBoxes(visited, s, dir);
}
return(true);
}
private bool TryMoveStickyBox(StickyBox box, IntVec dir)
{
HashSet <StickyBox> visited = new HashSet <StickyBox>();
return(MoveStickyBoxes(visited, box, dir));
}
