// seperates the internal points into a logical grid of cells
internal void seperatePointsIntoGridCells(List <DelaunayTriangulator.Vertex> points, int angle)
{
GridRotation = Geometry.createGridTransformation(angle, BoundsWidth, BoundsHeight, NumFrames);
SeperatedPoints = new Dictionary <SKPointI, HashSet <SKPoint> >();
SKPointI gridIndex = new SKPointI();
var newPoint = new SKPoint();
foreach (var point in points)
{
newPoint.X = point.x;
newPoint.Y = point.y;
GridRotation.CellCoordsFromOriginPoint(ref gridIndex, newPoint);
//if the SeperatedPoints distionary does not have a point already, initialize the list at that key
if (!SeperatedPoints.ContainsKey(gridIndex))
{
SeperatedPoints[gridIndex] = new HashSet <SKPoint>();
}
SeperatedPoints[gridIndex].Add(newPoint);
}
}
//saves
internal HashSet <SKPoint> getTouchAreaRecPoints()
{
var touch = new HashSet <SKPoint>();
var BL = new SKPoint(TouchLocation.X - TouchRadius, TouchLocation.Y - TouchRadius);
var TR = new SKPoint(TouchLocation.X + TouchRadius, TouchLocation.Y + TouchRadius);
var BLindex = new SKPointI();
var TRindex = new SKPointI();
GridRotation.CellCoordsFromOriginPoint(ref BLindex, BL);
GridRotation.CellCoordsFromOriginPoint(ref TRindex, TR);
var upperX = TRindex.X > BLindex.X ? TRindex.X : BLindex.X;
var lowerX = TRindex.X < BLindex.X ? TRindex.X : BLindex.X;
var upperY = TRindex.Y > BLindex.Y ? TRindex.Y : BLindex.Y;
var lowerY = TRindex.Y < BLindex.Y ? TRindex.Y : BLindex.Y;
var p = new SKPointI();
for (var i = lowerX; i <= upperX; i++)
{
for (var j = lowerY; j <= upperY; j++)
{
p.X = i;
p.Y = j;
if (SeperatedPoints.ContainsKey(p))
{
touch.UnionWith(SeperatedPoints[p]);
}
}
}
return(touch);
}