Visualizations of Perceptually Relevant Light Parameters

Light strongly influences the appearance of the shape and material of an object. For example increasing the light diffuseness makes an object look more flat and matte. We consider the actual light resulting from sources and optical interactions in the scene. Taking into account the interdependence of light and scene properties, it is not easy to optimize lighting. A light design workflow is essentially an iterative process of adjusting lights and objects in a scene to achieve the desired appearance. Typically, a time-consuming rendering is used to see the results of the last manipulations. We propose a method visualizing the light parameters commonly used by light professionals and, more importantly, proven to be basic light characteristics for which human observers are sensitive: "intensity", direction and diffuseness. The visualizations are presented in the viewport and therefore are much faster than rendering. They show the light flow - global changes of the parameters - over a scene using grids of shapes or visual gauge objects.