Doppler Dome is based on the Doppler effect.
The idea is to have a plugin that can take a constant car engine sound or something, and make it seem like the car speeds past you. Not just past you but it could do a circle near you, or accelerate then slow down.
It can be adjusted to have different levels for pan, volume, and pitch effects, so it can make the equivalent of a chorus, panner, tremolo, vibrato, etc, but with a totally flexible LFO / automation source.
The Blend control will mix the pitch effect with the dry signal, this is a bit like a chorus or modulated delay. The Pitch Scale knob determines how much pitch is affected, it can be turned off by setting it to zero. The Volume Scale Scale knob determines how much volume affected, based on distance. The Pan Scale Scale knob determines how much L/R position is affected, based on left and right position.
A MIDI not on message can be used to reset the path position and sync it with the audio or MIDI events.