A lot of ShaderToy demos share the Ray Marching algorithm to render the scene, but they are often written with a very compact style and i can't find any straightforward examples or explanation.
So what is Ray Marching? Some comments suggests that it is a variation of Sphere Tracing. What are the computational advantages of a such approach?
Ray marching is a method for rendering scenes by casting rays from the camera through the scene and determining the intersection point of each ray with objects in the scene, in a continuous manner. This is different from traditional ray tracing methods where each object has a list of intersections with the ray, and the intersection with the closest object is chosen to determine the final color of a pixel.

Instead of pre-calculating intersections for each object, ray marching calculates
Regards,
Luca
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Ray marching is a type of ray tracing technique that calculates intersections with geometric objects by iteratively stepping forward along a ray until an object is hit, or a maximum limit is reached. This allows for real-time rendering of complex scenes because the computations can be simplified and parallelized effectively.
Compared to traditional ray tracing methods that use bounded tree structures such as kd-trees or BVHs to