The present invention is a method of hydrodynamics-based gridding for creating geologic models of subsurface volumes, such as reservoirs. The video coder may determine a co-located block of the reference picture. A valid pixel flag indicating that a valid pixel is present within the block is stored in the rendering information buffer. The voltage regulator has a power output in communication with the output terminal. A resource position generating unit, supplied with the resource assignment information SRA, calculates a relative position of an empty resource with respect to a multiplex position of a pilot signal and outputs the relative position information SRP. Patient translation structure provides coordinated translational movement of the patient’s upper body along the respective patient support in a caudad or cephalad direction as the support structures are angled upwardly or downwardly for maintaining proper spinal biomechanics and avoiding undue spinal traction or compression.