private void ensureExtraCapacity(int index)
{
//2 * parentIndex + 2
if (2 * index + 2 >= capacity)
{
BeachLineItem[] newArray = new BeachLineItem[2 * index + 3];
Array.Copy(beachTree, newArray, beachTree.Length);
beachTree = newArray;
capacity = beachTree.Length;
}
}
internal void HandleVertexEvent(Vector2 eventLocation, List <VHalfEdge> halfEdges, ref Dictionary <VEvent, VEventInfo> events, ref VTile[] tiles, int curTileIndex, ref PriorityQueue priorityQueue)
{
//locate the existing arc (if any) that is above the new site
int arcIndex = getExistingArc(beachTree, eventLocation);
//break the arc by replacing the leaf node with a sub tree representing
//the new arc and its break points
tiles[curTileIndex] = new VTile(eventLocation);
if (arcIndex == -1)
{
//beachTree[0] = new VArc(eventLocation);
beachTree[0] = new BeachLineItem()
{
IsEdge = false,
ArcIndex = arcs.Count,
};
arcs.Add(new VArc(eventLocation, tiles[curTileIndex]));
}
else
{
//Corresponding leaf replaced by a new sub-tree
removeRelatedCircleEvent(arcIndex, eventLocation, ref events);
VArc newArc = new VArc(eventLocation, tiles[curTileIndex]);
VArc arc = arcs[beachTree[arcIndex].ArcIndex];
//Add two half-edge records in the doubly linked list
VHalfEdge halfEdge = new VHalfEdge()//pm pl
{
Tile = newArc.Tile,
};
halfEdges.Add(halfEdge);
VHalfEdge twinHalfEdge = new VHalfEdge()//pl pm
{
Tile = arc.Tile,
};
//edges[edges.Count - 1].HalfEdge = halfEdge;
//edges[edges.Count - 2].HalfEdge = twinHalfEdge;
halfEdges.Add(twinHalfEdge);
halfEdge.Twin = twinHalfEdge;
twinHalfEdge.Twin = halfEdge;
newArc.Tile.Neighbors.AddLast(arc.Tile);
arc.Tile.Neighbors.AddLast(newArc.Tile);
newArc.Tile.Edges.AddLast(halfEdge); //halfedge belongs to the newArc created
arc.Tile.Edges.AddLast(twinHalfEdge); //created twinedge belongs to the split collided arc
int leftChildIndex = getLeftChildIndex(arcIndex);
beachTree[leftChildIndex] = new BeachLineItem()
{
IsEdge = false,
ArcIndex = beachTree[arcIndex].ArcIndex,
}; //arc;
int rChild = getRightChildIndex(arcIndex);
ensureExtraCapacity(getLeftChildIndex(rChild));
beachTree[getLeftChildIndex(rChild)] = new BeachLineItem()
{
IsEdge = false,
ArcIndex = arcs.Count,
}; //newArc;
arcs.Add(newArc);
ensureExtraCapacity(getRightChildIndex(rChild));
beachTree[getRightChildIndex(rChild)] = new BeachLineItem()
{
IsEdge = false,
ArcIndex = arcs.Count,
}; //arc;
arcs.Add(new VArc(arc.Focus, arc.Tile));
beachTree[rChild] = new BeachLineItem()
{
IsEdge = true,
EdgeIndex = edges.Count,
};
edges.Add(new VEdge(beachTree[getLeftChildIndex(rChild)].ArcIndex, beachTree[getRightChildIndex(rChild)].ArcIndex, twinHalfEdge));
//edges[edges.Count - 1].HalfEdge = halfEdges.Count;
beachTree[arcIndex] = new BeachLineItem()
{
IsEdge = true,
EdgeIndex = edges.Count,
};
edges.Add(new VEdge(beachTree[leftChildIndex].ArcIndex, beachTree[getLeftChildIndex(rChild)].ArcIndex, halfEdge));
//edges[edges.Count - 1].HalfEdge = halfEdges.Count + 1;
//Check for potential circle events, add them to event queue if they exist
if (!hasParent(arcIndex))
{
//there is no possible circle event,
return;
}
//int parentIndex = getParentIndex(arcIndex);//<-- get first right parent index //int rightParentIndex = getRightParentIndex(arcIndex);
VEdge leftCreatedHalfEdge = edges[beachTree[arcIndex].EdgeIndex];
int leftParentIndex = getFirstLeftParentIndex(arcIndex);
//if(leftParentIndex == -1) -> then there is no need to check for edges on the left
if (leftParentIndex >= 0)
{
VEdge leftParentEdge = edges[beachTree[leftParentIndex].EdgeIndex];
Vector2 intercept = getRayIntercept(leftCreatedHalfEdge, leftParentEdge, eventLocation);
if (intercept.Y != float.NegativeInfinity)//probably don't need this check?
{
//we want circle event location to be droped lower by radius to x val
//we want to calculate radius and store it with the event
//we add starting point to the halfedge that belongs to the newArc
//halfEdge.Start = intercept;
float radius = Vector2.Distance((arcs[leftCreatedHalfEdge.LeftArcIndex]).Focus, intercept);
intercept.Y -= radius;
VEvent newCircleEvent = new VEvent(intercept, EventType.CircleEvent);
priorityQueue.Enqueue(newCircleEvent);
events.Add(newCircleEvent, new VEventInfo()
{
Radius = radius,
VEdgeOneIndex = leftParentIndex, //pk pl
VEdgeTwoIndex = arcIndex, //pl pm //rChild?
});
//add to leafs
arc = arcs[leftCreatedHalfEdge.LeftArcIndex];
arc.CircleEventLocations.Add(newCircleEvent);
//beachTree[edgeOne.LeftArcIndex] = arc;
arc = arcs[leftCreatedHalfEdge.RightArcIndex];
arc.CircleEventLocations.Add(newCircleEvent);
//beachTree[edgeOne.LeftArcIndex] = arc;
arc = arcs[leftParentEdge.LeftArcIndex];
arc.CircleEventLocations.Add(newCircleEvent);
//beachTree[edgeTwo.RightArcIndex] = arc;
}
}
VEdge rightCreatedHalfEdge = edges[beachTree[rChild].EdgeIndex];
int rightParentIndex = getFirstRightParentIndex(arcIndex);
//if(rightParentIndex == -1) -> then there is no need to check for edges on the right
if (rightParentIndex >= 0)
{
VEdge rightParentEdge = edges[beachTree[rightParentIndex].EdgeIndex];//(VEdge)beachTree[parentIndex];
Vector2 intercept = getRayIntercept(rightCreatedHalfEdge, rightParentEdge, eventLocation);
if (intercept.Y != float.NegativeInfinity)
{
//we want circle event location to be droped lower by radius to x val
//we want to calculate radius and store it with the event
//we add starting point to the halfedge that belongs to the newArc
//twinHalfEdge.Start = intercept;
float radius = Vector2.Distance((arcs[rightCreatedHalfEdge.LeftArcIndex]).Focus, intercept);
intercept.Y -= radius;
VEvent newCircleEvent = new VEvent(intercept, EventType.CircleEvent);
priorityQueue.Enqueue(newCircleEvent);
events.Add(newCircleEvent, new VEventInfo()
{
Radius = radius,
VEdgeOneIndex = rightParentIndex, //pk pl
VEdgeTwoIndex = rChild, //pl pm
});
//add to leafs
arc = arcs[rightCreatedHalfEdge.LeftArcIndex];
arc.CircleEventLocations.Add(newCircleEvent);
//beachTree[edgeOne.LeftArcIndex] = arc;
arc = arcs[rightCreatedHalfEdge.RightArcIndex];
arc.CircleEventLocations.Add(newCircleEvent);
//beachTree[edgeOne.LeftArcIndex] = arc;
arc = arcs[rightParentEdge.RightArcIndex];
arc.CircleEventLocations.Add(newCircleEvent);
//beachTree[edgeTwo.RightArcIndex] = arc;
}
}
}
}