Query Illumination

Used to display the amount of light reflected by (Luminance) or reaching (Illuminance) the point on the first visible surface under the screen pointer. For example, if you point at a surface behind a window, the values displayed will be for the window, as this is the first surface encountered. The value is displayed in Lumens/Master Unit², followed by the illuminance in each of the RGB components. If you select a background pixel, or when the requested surface has not been processed for global illumination, then the message “No illumination information for selection” appears.

This tool works only with an existing solution. That is, when a Radiosity or Particle Traced solution is present in memory.

Tool Setting	Effect
Continuous Updates	If on, the values for Luminance and Illuminance update continuously in the status bar as the pointer moves in the view. Additionally, if you hover the pointer in the view, a tool tip displays the illumination values.
Display	Sets the value displayed. Luminance — Displays the amount of light reflected by the surface at the pointer position. Illuminance — Displays the amount of light reaching the surface at the pointer position.

Tool Setting

Effect

Continuous Updates

If on, the values for Luminance and Illuminance update continuously in the status bar as the pointer moves in the view. Additionally, if you hover the pointer in the view, a tool tip displays the illumination values.

Display

Sets the value displayed.

Luminance

Illuminance

To query a particle traced, or radiosity solution

Select the Query Illumination tool.

(Optional) Turn on Continuous Updates.

From the Display option menu, choose Luminance or Illuminance.

With Continuous Updates on, as you move the pointer across the screen, the illumination values are displayed.
or
If Continuous Updates is off, enter a data point in a view, at the required point, to display the illumination values.

Key-in: RADIOSITY QUERY