/// <summary>
/// Returns the position of the nearest vertex.
/// </summary>
/// <returns>
/// Position of the nearest vertex.
/// </returns>
///
/// <param name="grid">
/// The rectangular grid instance.
/// </param>
/// <param name="point">
/// Point in world space.
/// </param>
/// <param name="system">
/// Coordinate system to use.
/// </param>
///
/// <remarks>
/// Returns the position of the nearest vertex from a given point in
/// either grid- or world space.
/// </remarks>
public static Vector3 NearestVertex(this PolarGrid grid, Vector3 point, CoordinateSystem system)
{
var gridPoint = grid.WorldToGrid(point);
for (var i = 0; i < 3; ++i)
{
gridPoint[i] = Mathf.Round(gridPoint[i]);
}
return(GridToCoordinateSystem(grid, gridPoint, system));
}
/// <summary>
/// Returns the position of the nearest face.
/// </summary>
/// <returns>
/// Position of the nearest face.
/// </returns>
/// <param name="grid">
/// The rectangular grid instance.
/// </param>
/// <param name="point">
/// Point in world space.
/// </param>
/// <param name="system">
/// Coordinate system to use.
/// </param>
///
/// <remarks>
/// <para>
/// Returns the coordinates of a face on the grid closest to a
/// given point. Since the face is enclosed by four vertices, the
/// returned value is the point in between all four of the
/// vertices. You also need to specify on which plane the face
/// lies.
/// </para>
/// </remarks>
public static Vector3 NearestFace(this PolarGrid grid,
Vector3 point,
CoordinateSystem system)
{
Vector3 gridPoint = grid.WorldToGrid(point);
gridPoint.x = Mathf.Floor(gridPoint.x) + .5f;
gridPoint.y = Mathf.Floor(gridPoint.y) + .5f;
gridPoint.z = Mathf.Round(gridPoint.z);
return(GridToCoordinateSystem(grid, gridPoint, system));
}
private static Vector3 GridToCoordinateSystem(PolarGrid grid, Vector3 gridPoint, CoordinateSystem system)
{
switch (system)
{
case CoordinateSystem.Grid:
return(gridPoint);
case CoordinateSystem.World:
return(grid.GridToWorld(gridPoint));
case CoordinateSystem.Cylindric:
return(grid.GridToPolar(gridPoint));
default:
var error = string.Format("Error: Coordinate system \"{0}\" unimplemented", system);
throw new System.ComponentModel.InvalidEnumArgumentException(error);
}
}
