Houdini 17.0 Nodes VOP nodes

Multiply Constant VOP node

Multiplies the incoming value by a constant.

Simpler version of the Multiply operator; does not require a second input. Accepts integer, float, vector, or vector4 types. Use to scale a value by a constant.

Examples

The following examples include this node.

Street Crowd Example Example for Crowd Solver dynamics node

Crowd example showing a street setup with two agent groups

The setup creates two groups of agents. The yellow agents are zombies which follow a path of the street. The blue agents are living pedestrians that wander around until they come into proximity of the zombies and then they swtich into a running state.

Triggers to change agent states are setup in the crowd_sim dopnet. The zombies group uses proximity to the stoplights and the color of the light to transition into a standing state when lights are red. The living group transition into a running state when they get close to the zombie agents.

Note

The animation clips need to be baked out before playing the scene. This should happen automatically if example is created from Crowds shelf. Otherwise save scene file to a location of your choice and click Render on '/obj/bake_cycles' ropnet to write out the files. The default path for the files is ${HIP}/agents.

FlipColumn Example for FLIP Solver dynamics node

This example demonstrates how a mixture of fluid colours can have their colour changed by a collision with a static object.

CurveForce Example for POP Curve Force dynamics node

This example demonstrates the use of the POP Curve Force node to control the flow of a particle sim AND a flip fluid sim.

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.

StyleDisplacement Example for Material shader node

This is an example file showing an object made up of two quads, one with a bump map, the other with true displacement. This object is duplicated, and the second copy uses a style sheet to reverse the material assignments on the two quads.

RandomMaterial Example for Attribute String Edit geometry node

This example demonstrates how to use the Attrib String Edit SOP to modify String primitive attributes and randomize the colours on a grid on a per-primitive basis.

FurBallWorkflow Example for Fur geometry node

This example demonstrates how the Fur SOP and Mantra Fur Procedural can be applied to an animated skin geometry. CVEX shaders are used to apply a custom look to the hairs based upon attributes assigned to the geometry.

AlphaOmega Example for Points from Volume geometry node

This example demonstrates how to use a Points From Volume SOP to create a target goal for a flip simulation and make it fill a given piece of geometry.

UnpackWithStyle Example for Unpack geometry node

This example demonstrates the Unpack SOPs ability to evaluate style sheet information while unpacking. Nested packed primitives are used to demonstrate partial unpacking while still preserving styling information. This example also demonstrates the use of a Python SOP to extract information from the per-primitive style sheets.

ImportVolumes Example for Volume VOP geometry node

This example shows how to import multiple volumes into a Volume VOP SOP.

WornMetal Example for Curvature VOP node

This example shows how the curvature vop can be added to a shader network to add a worn or distressed look to your material.

See also

VOP nodes