Houdini 16.5 Nodes VOP nodes

Ambient VOP node

Generates a color using ambient lighting model calculation.

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This VOP uses the ambient lighting model calculation to generate a color. This lighting model return black if there are not specific ambient lights. These are the only lights used in this calculation. PBR ignores this VOP.

Inputs

Ka

The ambient intensity.

A floating point value used to darken or lighten ambient contribution.

amb

The ambient color.

This color is most often the main surface color in a material.

Outputs

color

The ambient color contribution:

Ka * amb * ambient()

illum

Just ambient lighting without the multiplication by the ambient intensity

PBR ignores this calculation.

Examples

The following examples include this node.

MotionVector Example for Mantra render node

The example demonstrates how to generate a motion vector layer for post-velocity compositing. Load the example and render 5 frames. Then in the image viewer, switch from 'C' (colour) to 'motion_vector' to see the results.

RampReference

This example demonstrates the use of ramps and referenced ramps which are animated over time.

FirePit Example for Material shader node

Note

No geometry is animated in this file. All animation is achieved by animating the textures

Flames are grids so that UV textures can easily be applied, they are then warped around a metaball using a magnet SOP. The flames are then assigned to either a yellow or blue Flames texture. The Flames' opacity mask wrap is set to Decal to prevent the texture from repeating and showing a single pixel ring at the top of the flame geometry. I'm also using a mask file named flameOpacMap.jpg to enhance the flames' shape at the top. The noise offset has been animated over $T with an greater emphasis on the Y axis so that the flames look like they are rising. This is the same reason the Noise jitter is larger for the Y axis as well.

The coals are spheres that have been copy stamped onto a deformed grid. Using Attribute Create surface nodes I am able to override and copy stamp the lava texture’s parameters at the SOP level so that local variables, such as $BBY, can be used to animate the texture. This way the texture’s crust and its crust values can be used only to form the tops of the coals. This reserves the lava aspect of the texture to be used on the bottoms of the coals. The lava intensity (Kd attribute) is then stamped and animated to create the look of embers on the bottom of coals glowing.

FurTextureMap Example for Fur geometry node

This example demonstrates how to use a texturemap to color fur.

See also

VOP nodes