Ryan James Smith, a Lead Technical Artist at Sony Santa Monica, has recently shared a look at a physically accurate black hole with a volumetric accretion disk created in Unreal Engine 4. The artist noted that the black hole "spin warps space-time, causing further space warp and doppler shift of light".
"I bent light rays around the singularity. This whole thing is essentially a complex shader applied to an inverted sphere," wrote the artist in one of the replies on Twitter. "The ray starts at Camera and fires off along the view vector. I "Step" the light ray and apply a gravitational force every step of the way."