Editing Ray tracing (graphics) (section)

=== Disadvantages ===
A serious disadvantage of ray tracing is performance (though it can in theory be faster than traditional scanline rendering depending on scene complexity vs. number of pixels on-screen). Until the late 2010s, ray tracing in real time was usually considered impossible on consumer hardware for nontrivial tasks. Scanline algorithms and other algorithms use data coherence to share computations between pixels, while ray tracing normally starts the process anew, treating each eye ray separately. However, this separation offers other advantages, such as the ability to shoot more rays as needed to perform [[spatial anti-aliasing]] and improve image quality where needed.

Whitted-style recursive ray tracing handles interreflection and optical effects such as refraction, but is not generally [[photorealistic rendering|photorealistic]]. Improved realism occurs when the [[rendering equation]] is fully evaluated, as the equation conceptually includes every physical effect of light flow. However, this is infeasible given the computing resources required, and the limitations on geometric and material modeling fidelity. [[Path tracing]] is an algorithm for evaluating the rendering equation and thus gives a higher fidelity simulations of real-world lighting.