/// <summary>
/// sets the vertices without copying over the data from verts to the local List.
/// </summary>
/// <param name="verts">Verts.</param>
public void setVerticesNoCopy(Vertices verts)
{
Debug.Assert(verts.Count >= 3 && verts.Count <= Settings.maxPolygonVertices);
_vertices = verts;
if (Settings.useConvexHullPolygons)
{
// FPE note: This check is required as the GiftWrap algorithm early exits on triangles
// So instead of giftwrapping a triangle, we just force it to be clock wise.
if (_vertices.Count <= 3)
{
_vertices.forceCounterClockWise();
}
else
{
_vertices = GiftWrap.getConvexHull(_vertices);
}
}
if (_normals == null)
{
_normals = new Vertices(_vertices.Count);
}
else
{
_normals.Clear();
}
// Compute normals. Ensure the edges have non-zero length.
for (var i = 0; i < _vertices.Count; ++i)
{
var next = i + 1 < _vertices.Count ? i + 1 : 0;
var edge = _vertices[next] - _vertices[i];
Debug.Assert(edge.LengthSquared() > Settings.epsilon * Settings.epsilon);
// FPE optimization: Normals.Add(MathHelper.Cross(edge, 1.0f));
var temp = new Vector2(edge.Y, -edge.X);
Nez.Vector2Ext.normalize(ref temp);
_normals.Add(temp);
}
// Compute the polygon mass data
computeProperties();
}
static bool validatePolygon(Vertices polygon)
{
var errorCode = polygon.checkPolygon();
if (errorCode == PolygonError.InvalidAmountOfVertices || errorCode == PolygonError.AreaTooSmall || errorCode == PolygonError.SideTooSmall || errorCode == PolygonError.NotSimple)
{
return(false);
}
if (errorCode == PolygonError.NotCounterClockWise) //NotCounterCloseWise is the last check in CheckPolygon(), thus we don't need to call ValidatePolygon again.
{
polygon.Reverse();
}
if (errorCode == PolygonError.NotConvex)
{
polygon = GiftWrap.getConvexHull(polygon);
return(validatePolygon(polygon));
}
return(true);
}