public bool NoContactCertainty(IConvex2D shape)
{
float minA = 0;
float maxA = 0;
float minB = 0;
float maxB = 0;
// Only check up & right normals for an AABB since down & left are the same axes
shape.Project(Vector2.up, ref minA, ref maxA);
this.Project(Vector2.up, ref minB, ref maxB);
// Check if the polygon projections are currentlty NOT intersecting
if (Utility.IntervalDistance(minA, maxA, minB, maxB) > 0)
{
return(true);
}
shape.Project(Vector2.right, ref minA, ref maxA);
this.Project(Vector2.right, ref minB, ref maxB);
// Check if the polygon projections are currentlty NOT intersecting
if (Utility.IntervalDistance(minA, maxA, minB, maxB) > 0)
{
return(true);
}
return(false);
}
/// <summary>
/// Adds a unit.
/// </summary>
public void Add(T unit, IConvex2D shape)
{
foreach (var cell in _getOrCreateSupercover(shape))
{
cell.Add(new UnitWrapper(unit, shape));
}
Count++;
}
/// <summary>
/// Enumerates all cells that are in the supercover of shape and creates a new cell if that cell was null
/// </summary>
protected IEnumerable <TCell> _getOrCreateSupercover(IConvex2D shape)
{
foreach (var location in shape.Supercover(this))
{
if (_cells[location.x, location.y] == null)
{
_cells[location.x, location.y] = _createNewCell(location);
}
yield return(_cells[location.x, location.y]);
}
}
/// <summary>
/// Adds a unit.
/// </summary>
public void Add(TKey key, T unit, IConvex2D shape)
{
UnitWrapper wrapper = new UnitWrapper(unit, shape);
foreach (var cell in _getOrCreateSupercover(shape))
{
cell.Add(key, wrapper);
}
wrappers.Add(key, wrapper);
Count++;
}
/// <summary>
/// Enumarates all objects that overlap with shape
/// </summary>
public IEnumerable <T> Contact(IConvex2D shape)
{
// Increment our query number to prevent yielding a unit multiple times if it spans more than one cell
_queryNumber++;
foreach (Vector2Int cellIndex in shape.Supercover(this))
{
if (_cells[cellIndex.x, cellIndex.y] != null)
{
foreach (var wrapper in _cells[cellIndex.x, cellIndex.y].Contact(shape, (u) => true, _queryNumber))
{
yield return(wrapper.Unit);
}
}
}
}
/// <summary>
/// Returns the first object found that contacts shape for which a predicate evaluates to true. It might speak an alien language to us humans.
/// </summary>
public T FirstContactWhich(IConvex2D shape, Predicate <T> predicate)
{
_queryNumber++;
foreach (Vector2Int cellIndex in shape.Supercover(this))
{
if (_cells[cellIndex.x, cellIndex.y] != null)
{
foreach (var wrapper in _cells[cellIndex.x, cellIndex.y].Contact(shape, predicate, _queryNumber))
{
return(wrapper.Unit);
}
}
}
return(default(T));
}
/// <summary>
/// Updates a unit's position / shape
/// </summary>
public void Update(TKey key, IConvex2D newShape)
{
UnitWrapper wrapper = wrappers[key];
foreach (var cell in _getOrCreateSupercover(wrapper.Shape))
{
cell.Remove(key);
}
var newWrapper = new UnitWrapper(wrapper.Unit, newShape);
foreach (var cell in _getOrCreateSupercover(newShape))
{
cell.Add(key, newWrapper);
}
wrappers[key] = newWrapper;
}
/// <summary>
/// Returns all units in this cell that contact shape
/// </summary>
public IEnumerable <UnitWrapper> Contact(IConvex2D shape, Predicate <T> predicate, int queryNumber)
{
foreach (var wrapper in _unitWrappers)
{
// Make sure to check each unit only once. Certain shapes might span multiple cells.
if (!wrapper.Once(queryNumber))
{
continue;
}
if (!shape.NoContactCertainty(wrapper.Shape) &&
!wrapper.Shape.NoContactCertainty(shape) &&
predicate(wrapper.Unit))
{
yield return(wrapper);
}
}
}
public bool NoContactCertainty(IConvex2D shape)
{
float minA = 0;
float maxA = 0;
float minB = 0;
float maxB = 0;
Vector2 normal = new Vector2(-(w.y - v.y), w.x - v.x).normalized;
shape.Project(normal, ref minA, ref maxA);
this.Project(normal, ref minB, ref maxB);
// Check if the polygon projections are currentlty NOT intersecting
if (Utility.IntervalDistance(minA, maxA, minB, maxB) > 0)
{
return(true);
}
return(false);
}
/// <summary>
/// Returns the first object found that contacts shape. It might speak an alien language to us humans.
/// </summary>
public T FirstContact(IConvex2D shape)
{
_queryNumber++;
int cellsSearched = 0;
foreach (Vector2Int cellIndex in shape.Supercover(this))
{
cellsSearched++;
if (_cells[cellIndex.x, cellIndex.y] != null)
{
foreach (var wrapper in _cells[cellIndex.x, cellIndex.y].Contact(shape, (u) => true, _queryNumber))
{
return(wrapper.Unit);
}
}
}
AverageCellsSearched = Mathf.Lerp(AverageCellsSearched, cellsSearched, 0.5f);
return(default(T));
}
/// <summary>
/// Enumarates all objects that overlap with a convex shape and for which a predicate evaluates to true
/// </summary>
public IEnumerable <T> ContactWhich(IConvex2D shape, Predicate <T> predicate)
{
// Increment our query number to prevent yielding a unit multiple times if it spans more than one cell
_queryNumber++;
int cellsSearched = 0;
int unitsAcc = 0;
foreach (Vector2Int cellIndex in shape.Supercover(this))
{
cellsSearched++;
if (_cells[cellIndex.x, cellIndex.y] != null)
{
unitsAcc += _cells[cellIndex.x, cellIndex.y].Count;
foreach (var wrapper in _cells[cellIndex.x, cellIndex.y].Contact(shape, predicate, _queryNumber))
{
yield return(wrapper.Unit);
}
}
}
AverageCellsSearched = Mathf.Lerp(AverageCellsSearched, cellsSearched, 0.5f);
AverageUnitsPerCell = (float)unitsAcc / cellsSearched;
}
public bool NoContactCertainty(IConvex2D shape)
{
return(this.shape.NoContactCertainty(shape));
}
public bool NoContactCertainty(IConvex2D shape)
{
return(shape.DistanceSquared(new Vector2(x, y)) > 0);
}
public void UpdateShape(int key, IConvex2D shape)
{
_grid.Update(key, shape);
}
private int _lastQueryNumber; // Keeps track of the last query number that has been made to prevent duplicate results
public UnitWrapper(T unit, IConvex2D shape)
{
Shape = shape;
Unit = unit;
}
public CachedShape(IGridDimensions2D grid, IConvex2D shape)
{
this.shape = shape;
this.supercover = shape.Supercover(grid).ToArray();
}
/// <summary>
/// No SAT here
/// A shape doesn't touch a circle when it's closest distance to the circle's center is greater than the circle's radius
/// </summary>
public bool NoContactCertainty(IConvex2D shape)
{
return(shape.DistanceSquared(center) > radius * radius);
}
