In computational geometry and computer graphics, a shape defined by a series of connected points can exhibit either convexity or concavity. A convex shape has no internal angles greater than 180 degrees; any line segment drawn between two points within the shape remains entirely within the shape. Conversely, a shape possessing at least one internal angle exceeding 180 degrees is classified as concave. Consider the difference between a simple rectangle (convex) and a star shape (concave). The star’s points create reflex angles, classifying it as the latter.
Distinguishing between these shape types is fundamental in various fields. Collision detection algorithms, for example, often employ different strategies depending on the concavity of involved objects. Concave shapes present greater complexity, requiring more sophisticated methods to accurately determine intersections. Similarly, image processing techniques, particularly those involving shape recognition and analysis, benefit from the ability to categorize shapes based on this property. The efficient rendering and manipulation of complex figures in computer graphics also rely on understanding and processing concavity. Historically, the development of efficient algorithms to manage these shapes marked a significant advance in computational geometry, enabling more realistic and complex simulations and representations.
