mental ray Architectural and Design Visualization Shader Library

3.5 Sun Parameters 65• saturation is also an artistic control, where 1.0 is the physically calculated saturationlevel. The parameter ranges from 0.0 (black and white) to 2.0 (extremely boostedsaturation)3.5 Sun ParametersThe mia physicalsun is responsible for the color and intensity of the sunlight, as well asemitting photons from the sun. The shader should be applied as light shader and photonemission shader on a directional light source (it does not work on any other light type).declare shader "mia_physicalsun" (boolean "on"default on,scalar "multiplier" default 1.0,color "rgb_unit_conversion" default 0.0001 0.0001 0.0001,scalar "haze" default 0.0,scalar "redblueshift" default 0.0,scalar "saturation" default 1.0,scalar "horizon_height" default 0.0,scalar "shadow_softness" default 1.0,integer "samples" default 8,vector "photon_bbox_min",vector "photon_bbox_max",boolean "automatic_photon_energy",boolean "y_is_up",integer "illuminance_mode" default 0,scalar "direct_normal_illuminance" default 0.0)version 6apply lightend declareAs mentioned above, the mia physicalsun contains several of the common parameters thatare exposed in the mia physicalsky as well (haze, redblueshift etc.). The value of theseparameters for the mia physicalsun should match those in the mia physicalsky. The parametersspecific to the mia physicalsun are as follows:• samples is the number of shadow samples for the soft shadows. If it is set to 0, no softshadows are generated.• shadow softness is the softness for the soft shadows. A value of 1.0 is the value whichmatches the softness of real solar shadow most accurately. Lower values makes theshadows sharper and higher softer.• When photon bbox min and photon bbox max are left set to 0,0,0 the photonbounding box will be calculated automatically by the shader. If these are set, they define