Describe the algorithm for computing the intersection of a line segment with a polygon in Computational Geometry.

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Describe the algorithm for computing the intersection of a line segment with a polygon in Computational Geometry.

The algorithm for computing the intersection of a line segment with a polygon in Computational Geometry can be achieved using the following steps:

1. Determine the intersection points between the line segment and each edge of the polygon. To do this, iterate through each edge of the polygon and check if there is an intersection between the line segment and the edge. This can be done using line intersection algorithms such as the Line-Line Intersection algorithm or the Line-Segment Intersection algorithm.

2. Check if the intersection points lie within the range of the line segment. For each intersection point, check if its coordinates lie within the range of the line segment. This can be done by comparing the x and y coordinates of the intersection point with the x and y coordinates of the line segment's endpoints.

3. Determine the intersection points that are inside the polygon. To do this, use the Ray Casting algorithm. Start from a point outside the polygon and cast a ray towards the intersection point. Count the number of times the ray intersects with the polygon's edges. If the count is odd, the intersection point is inside the polygon. If the count is even, the intersection point is outside the polygon.

4. Return the set of intersection points that are inside the polygon. Collect all the intersection points that are determined to be inside the polygon and return them as the result of the algorithm.

It is important to note that this algorithm assumes that the line segment and the polygon are in 2D space. Additionally, the algorithm may need to handle special cases such as when the line segment is coincident with an edge of the polygon or when the line segment lies completely inside or outside the polygon.