/**
* Returns a list containing lines connected to the given points. A line is a list of points.
* Only returns correct results for square or hex grids.
*
* @param IsNeighborsConnected a functions that returns true or false, depending on whether
* two points can be considered connected when they are neighbors. For example, if you want
* rays of points that refer to cells of the same color, you can pass in a functions that
* compares the DefaultColors of cells.
*
* @tparam TCell the type of cell of the grid that this algorithm takes.
* @tparam TPoint the type of point of the grid that this algorithm takes.
*
* @code
* private bool IsSameColour(point1, point2)
* {
* return grid[point1].Color == grid[point2].Color;
* }
*
* private SomeMethod()
* {
* ...
* var rays = GetConnectedRays<ColourCell, PointyHexPoint, PointyHexNeighborIndex>(
* grid, point, IsSameColour);
* ...
* }
* @endcode
*
* You can of course also use a lambda expression, like this:
*
* @code
* //The following code returns all lines that radiate from the given point,
*
* GetConnectedRays<ColourCell, PointyHexPoint, PointyHexNeighborIndex>(
* grid, point, (x, y) => grid[x].Color == grid[y].Color);
*
* @endcode
*/
public static IEnumerable <IEnumerable <TPoint> > GetConnectedRays <TCell, TPoint>(
AbstractUniformGrid <TCell, TPoint> grid,
TPoint point,
Func <TPoint, TPoint, bool> isNeighborsConnected)
where TPoint : IVectorPoint <TPoint>, IGridPoint <TPoint>
{
var lines = new List <IEnumerable <TPoint> >();
foreach (var direction in grid.GetNeighborDirections())
{
var line = new PointList <TPoint>();
var edge = point;
while (grid.Contains(edge) && isNeighborsConnected(point, edge))
{
line.Add(edge);
edge = edge.MoveBy(direction);
}
if (line.Count > 1)
{
lines.Add(line);
}
}
return(lines);
}
/**
* Gets the longest of the rays connected to this cell.
*
* @tparam TCell the type of cell of the grid that this algorithm takes.
* @tparam TPoint the type of point of the grid that this algorithm takes.
*
* @see GetConnectedRays
*/
public static IEnumerable <TPoint> GetLongestConnectedRay <TCell, TPoint>(
AbstractUniformGrid <TCell, TPoint> grid,
TPoint point,
Func <TPoint, TPoint, bool> isNeighborsConnected)
where TPoint : IVectorPoint <TPoint>, IGridPoint <TPoint>
{
var rays = GetConnectedRays(grid, point, isNeighborsConnected);
return(GetBiggestShape(rays));
}
public static IEnumerable <TPoint> GetNeighborDirections <TCell, TPoint>(this AbstractUniformGrid <TCell, TPoint> grid)
where TPoint : IGridPoint <TPoint>, IVectorPoint <TPoint>
{
return(grid.NeighborDirections);
}