/// <summary>
/// initialise the snake based upon a polygon shape
/// </summary>
/// <param name="binary_image"></param>
/// <param name="BlackOnWhite"></param>
/// <param name="initial_points"></param>
/// <param name="max_itterations"></param>
/// <param name="rnd"></param>
public void Snake(bool[,] binary_image, bool BlackOnWhite,
polygon2D initial_points,
int max_itterations,
Random rnd)
{
if (initial_points.x_points.Count > 1)
{
// get the perimeter length of the initial shape
float perimeter_length = initial_points.getPerimeterLength();
// distribute points evenly along the perimeter
int side_index = 0;
float side_length_total = 0;
for (int i = 0; i < no_of_points; i++)
{
// position of this point along the perimeter
float perimeter_position = i * perimeter_length / no_of_points;
float total = side_length_total;
while (total < perimeter_position)
{
side_length_total = total;
total += initial_points.getSideLength(side_index);
if (total < perimeter_position)
{
side_index++;
}
}
float side_length = initial_points.getSideLength(side_index);
if (side_length > 0)
{
float perimeter_diff = perimeter_position - side_length_total;
float fraction = perimeter_diff / side_length;
float tx = 0, ty = 0, bx = 0, by = 0;
initial_points.getSidePositions(side_index, ref tx, ref ty, ref bx, ref by);
float dx = bx - tx;
float dy = by - ty;
SnakePoint[i, SNAKE_X] = tx + (dx * fraction);
SnakePoint[i, SNAKE_Y] = ty + (dy * fraction);
}
}
Snake(binary_image, BlackOnWhite, max_itterations, rnd);
}
}
