This study designs geometrical perceived depth percentage (GPDP) to numerate and shade the geometric depth of a scene for a practical solution to visualize the stereoscopic perception without the need of any 3D device or special environment. In addition to the geometric relationship between object depth and focal distance, GPDP further considers the screen width and viewing distance for a more intuitive control metric of stereoscopy when comparing to parallax and disparity.
Along with the GPDP-based shading scheme, a stereoscopic comfort volume and depth perception markers can also be defined to form an intuitive auxiliary tool for the manipulation of stereoscopic parameters. These tools are easily implemented into any modern rendering pipeline, including interactive Autodesk Maya and off-line Pixar's RenderMan renderer.