_{Gobo filter -> spot_light. Image -> slide_map.}

The gobo filter can only be used with spot lights. In theatrical stage lighting, a gobo (or "cookie," slang for Cucoloris) is a thin sheet of metal with holes used to break up the light beam into an irregular, more natural pattern such as tree leaves, etc. In the computer graphics world, gobos are sometimes referred to as "slide projectors" (or sometimes "projector lights," but note that in Arnold the gobo is not a light source itself, but a filter applied to a spot light source). Any texture map or procedural shader can be projected through the light.

Filter Mode

The blending equation by which the gobo's slide map is combined with the lights output. Blend creates a default gobo effect. Replace multiplies the slide map over the spot light. Add multiplies the spot_light over the gobo. Sub inverts the RGB values of the slide map. Mix averages the results equally between the spot_light and the slide_map.

Slide Map

The texture map used to create the gobo effect.

Density

Controls the density of the gobo. Higher values will make the gobo more opaque, thereby letting less light through.

Offset

UV coordinate values used to offset the direction of the slide map.

S Scale

Scales the texture used for the slide map in the S direction.

T Scale

Scales the texture used for the slide map in the T direction.

S Wrap

Controls how the 2d texture map is repeated on a surface in the S direction.

T Wrap

Controls how the 2d texture map is repeated on a surface in the T direction.