Fake Ray Tracing
by Chris Michaelides ~ grVulture
This shader uses a simple ray marching technique to trace rays through the scene and accumulate the color and distance along the ray.
Keep in mind that this code is not a complete ray tracing solution and would not provide the same level of accuracy and realism as hardware-accelerated ray tracing.
The benefit is that this shader is not costly on performance, but still produces a relative good ray tracing effect.