👉 Casting math is a fundamental concept in computer graphics that determines the visibility of objects in a scene based on their distance from the camera. It involves calculating the distance from each pixel in the image plane to the closest object in the 3D scene, using a function called the distance function or casting function. This distance is then compared to a threshold value, known as the frustum plane distance, which represents the maximum distance from the camera that an object can be seen without being occluded by other objects. Objects closer than this threshold are considered visible and rendered, while those farther away are occluded and not drawn. The math typically involves vector arithmetic to compute the shortest distance between a point in space (the pixel position) and a point in 3D space (an object's position), often using techniques like ray tracing or bounding volume hierarchies to efficiently manage complex scenes. This process ensures that the rendered image accurately reflects what the human eye would perceive under ideal viewing conditions.
