public bool CheckCollision(Plane2D p)
{
float dir = (float)Vector.Multiply(Direction, p.Normal);
float dis = p.DistanceTo(Origin);
if (dis == 0)
{
return(true);
}
if (dir >= 0)
{
return(false);
}
float actualLength = -(dis / dir);
if (actualLength > Length)
{
return(false);
}
else
{
return(true);
}
}
public void RemovePolygon(Vector pos)
{
foreach (Polygon p in polygons)
{
bool isSelected = true;
foreach (Edge ed in p.edges)
{
Plane2D temp = new Plane2D(ed.start, ed.end);
if (temp.CheckCollision(pos) == true)
{
isSelected = false;
break;
}
}
if (isSelected == true)
{
polygons.Remove(p);
return;
}
}
}
/// <summary>
/// Checks that the polygon being made is valid.
/// </summary>
private void ValidatePoly()
{
if (tempNodes.Count >= 2)
{
// Checks if the polygon will overlap another.
List <Vector> tempArray = new List <Vector>(tempNodes);
if (nodeSelect != originNode)
{
tempArray.Add(nodeSelect);
}
Vector checkPoint = new Vector((tempArray.ElementAt(0).X + tempArray.ElementAt(1).X + tempArray.ElementAt(2).X) / 3,
(tempArray.ElementAt(0).Y + tempArray.ElementAt(1).Y + tempArray.ElementAt(2).Y) / 3);
Plane2D plane = new Plane2D(tempArray.ElementAt(0), tempArray.ElementAt(1));
if (plane.CheckCollision(checkPoint) == true)
{
tempArray.Reverse();
}
List <Plane2D> tempPlanes = new List <Plane2D>();
for (int i = 0; i < tempArray.Count; ++i)
{
if (i == tempArray.Count - 1)
{
tempPlanes.Add(new Plane2D(tempArray[i], tempArray[0]));
}
else
{
tempPlanes.Add(new Plane2D(tempArray[i], tempArray[i + 1]));
}
}
List <Vector> vSet = new List <Vector>();
foreach (Polygon p in polygons)
{
foreach (Edge ed in p.edges)
{
vSet.Add(ed.start);
}
}
foreach (Vector v in vSet)
{
bool isValid = false;
foreach (Plane2D pl in tempPlanes)
{
if (tempArray.Any(vec => vec == v) == true || pl.CheckCollision(v) == true)
{
isValid = true;
}
}
if (isValid == false)
{
nodeSelect = tempNodes.ElementAt(tempNodes.Count - 1);
MessageBox.Show("The polygon will overlap with another.", "Invalid edge");
return;
}
}
}
if (tempNodes.Count < 3)
{
tempNodes.Add(nodeSelect);
return;
}
int tailNode = tempNodes.Count - 1;
if (tempNodes.Count == 3)
{
Vector checkPoint = new Vector((tempNodes.ElementAt(0).X + tempNodes.ElementAt(1).X + tempNodes.ElementAt(2).X) / 3,
(tempNodes.ElementAt(0).Y + tempNodes.ElementAt(1).Y + tempNodes.ElementAt(2).Y) / 3);
Plane2D plane = new Plane2D(tempNodes.ElementAt(0), tempNodes.ElementAt(1));
if (plane.CheckCollision(checkPoint) == true)
{
polyPositive = false;
}
else
{
polyPositive = true;
}
}
// Checks if Polygon is convex by comparing with the other temp nodes.
Plane2D checkPlane;
if (nodeSelect != originNode)
{
if (polyPositive == true)
{
checkPlane = new Plane2D(tempNodes.ElementAt(tailNode), nodeSelect);
}
else
{
checkPlane = new Plane2D(nodeSelect, tempNodes.ElementAt(tailNode));
}
for (int i = 0; i < tailNode - 1; ++i)
{
if (checkPlane.CheckCollision(tempNodes.ElementAt(i)) == true)
{
nodeSelect = tempNodes.ElementAt(tailNode);
MessageBox.Show("Polygon needs to be convex.", "Invalid edge");
return;
}
}
}
else
{
if (polyPositive == true)
{
checkPlane = new Plane2D(tempNodes.ElementAt(tailNode), nodeSelect);
}
else
{
checkPlane = new Plane2D(nodeSelect, tempNodes.ElementAt(tailNode));
}
for (int i = 1; i < tailNode; ++i)
{
if (checkPlane.CheckCollision(tempNodes.ElementAt(i)) == true)
{
tempNodes.RemoveAt(tailNode);
nodeSelect = tempNodes.ElementAt(tailNode - 1);
MessageBox.Show("Polygon needs to be convex.", "Invalid edge");
return;
}
}
}
// Adds selected node if it passes all the validation checks.
if (nodeSelect != originNode)
{
tempNodes.Add(nodeSelect);
}
// Removes uneeded nodes that were inlined with the current node.
Vector cur = tempNodes.ElementAt(tailNode) - tempNodes.ElementAt(tailNode - 1);
Vector prev = tempNodes.ElementAt(tailNode - 1) - tempNodes.ElementAt(tailNode - 2);
float crossProduct = (float)(prev.X * cur.Y - prev.Y * cur.X);
if (crossProduct == 0)
{
tempNodes.RemoveAt(tailNode - 1);
}
// One last check to see if the polygon already exists. Then stores the polygon once it is complete.
if (tempNodes.Count >= 3 && nodeSelect == originNode)
{
foreach (Polygon p in polygons)
{
int edgeCount = p.edges.Count;
for (int i = 0; i < p.edges.Count; ++i)
{
foreach (Vector v in tempNodes)
{
if (v == p.edges.ElementAt(i).start)
{
edgeCount--;
if (edgeCount == 0)
{
originNode = new Vector(double.NaN, double.NaN);
nodeSelect = new Vector(double.NaN, double.NaN);
tempNodes.Clear();
polyPositive = true;
MessageBox.Show("Polygon is a duplicate and/or overlaps another.", "Invalid Polygon");
return;
}
}
}
}
}
var nodeArray = tempNodes.ToArray();
if (polyPositive == false)
{
Array.Reverse(nodeArray);
}
polygons.Add(new Polygon(nodeArray));
originNode = new Vector(double.NaN, double.NaN);
nodeSelect = new Vector(double.NaN, double.NaN);
tempNodes.Clear();
polyPositive = true;
}
}
