public DistanceGrid(Shape shape, Scalar spacing)
{
if (shape == null) { throw new ArgumentNullException("shape"); }
if (spacing <= 0) { throw new ArgumentOutOfRangeException("spacing"); }
//prepare the shape.
Matrix2D old = shape.Matrix;
Matrix2D ident = Matrix2D.Identity;
shape.ApplyMatrix(ref ident);
shape.CalcBoundingBox2D();
this.box = shape.BoundingBox2D;
this.gridSpacing = spacing;
this.gridSpacingInv = 1 / spacing;
int xSize = (int)Math.Ceiling((box.Upper.X - box.Lower.X) * gridSpacingInv) + 2;
int ySize = (int)Math.Ceiling((box.Upper.Y - box.Lower.Y) * gridSpacingInv) + 2;
this.nodes = new Scalar[xSize, ySize];
Vector2D vector;
vector.X = box.Lower.X;
for (int x = 0; x < xSize; ++x, vector.X += spacing)
{
vector.Y = box.Lower.Y;
for (int y = 0; y < ySize; ++y, vector.Y += spacing)
{
nodes[x, y] = shape.GetDistance(vector);
}
}
//restore the shape
shape.ApplyMatrix(ref old);
shape.CalcBoundingBox2D();
}
