private void FillHash()
{
//Average used to optimize cell size if AutoAdjustCellSize = true.
float average = 0;
for (int i = 0; i < _physicsSimulator.GeomList.Count; i++)
{
Geom geom = _physicsSimulator.GeomList[i];
//Note: Could do some checking here for geometries that should not be included in the hashmap
AABB aabb = geom.AABB;
if (AutoAdjustCellSize)
{
average += Math.Max(aabb.Max.X - aabb.Min.X, aabb.Max.Y - aabb.Min.Y);
}
int minX = (int)(aabb.Min.X * _cellSizeInv);
int maxX = (int)(aabb.Max.X * _cellSizeInv) + 1;
int minY = (int)(aabb.Min.Y * _cellSizeInv);
int maxY = (int)(aabb.Max.Y * _cellSizeInv) + 1;
for (int x = minX; x < maxX; x++)
{
for (int y = minY; y < maxY; y++)
{
long key = PairID.GetHash(x, y);
List <Geom> list;
if (!_hash.TryGetValue(key, out list))
{
list = new List <Geom>();
_hash.Add(key, list);
}
list.Add(geom);
}
}
}
if (AutoAdjustCellSize)
{
CellSize = 2 * average / (_physicsSimulator.GeomList.Count);
}
}
private void RunHash()
{
_keysToRemove.Clear();
foreach (KeyValuePair <long, List <Geom> > pair in _hash)
{
// If there are no geometries in the list. Remove it.
// If there are any geometries in the list, process them.
List <Geom> list = pair.Value;
if (list.Count == 0)
{
_keysToRemove.Add(pair.Key);
}
else
{
for (int i = 0; i < list.Count - 1; i++)
{
Geom geometryA = list[i];
for (int j = i + 1; j < list.Count; j++)
{
Geom geometryB = list[j];
if (!geometryA.body.Enabled || !geometryB.body.Enabled)
{
continue;
}
if ((geometryA.CollisionGroup == geometryB.CollisionGroup) &&
geometryA.CollisionGroup != 0 && geometryB.CollisionGroup != 0)
{
continue;
}
if (!geometryA.CollisionEnabled || !geometryB.CollisionEnabled)
{
continue;
}
if (geometryA.body.isStatic && geometryB.body.isStatic)
{
continue;
}
if (geometryA.body == geometryB.body)
{
continue;
}
if (((geometryA.CollisionCategories & geometryB.CollidesWith) == CollisionCategory.None) &
((geometryB.CollisionCategories & geometryA.CollidesWith) == CollisionCategory.None))
{
continue;
}
if (geometryA.IsGeometryIgnored(geometryB) || geometryB.IsGeometryIgnored(geometryA))
{
continue;
}
long key = PairID.GetId(geometryA.id, geometryB.id);
if (!_filter.ContainsKey(key))
{
_filter.Add(key, null);
//Check if there is intersection
bool intersection = AABB.Intersect(ref geometryA.AABB, ref geometryB.AABB);
//User can cancel collision
if (OnBroadPhaseCollision != null)
{
intersection = OnBroadPhaseCollision(geometryA, geometryB);
}
if (!intersection)
{
continue;
}
_physicsSimulator.ArbiterList.AddArbiterForGeomPair(_physicsSimulator, geometryA, geometryB);
}
}
}
list.Clear();
}
}
_filter.Clear();
//Remove all the empty lists from the hash
for (int index = 0; index < _keysToRemove.Count; ++index)
{
_hash.Remove(_keysToRemove[index]);
}
}