Houdini 17.0 Nodes VOP nodes

Fit Range VOP node

Takes the value in the source range and shifts it to the corresponding value in the destination range.

This operator takes the value in the source range (srcmin, srcmax) and shifts it to the corresponding value in the destination range (destmin, destmax). For example, fit(.3, 0, 1, 10, 20) would return the value 13.

Values outside the input range will be clamped to the input range.

Examples

The following examples include this node.

CrowdHeightField Example for Crowd Solver dynamics node

This example demonstrates using heightfields for terrain adaptation in the crowd solver, and for collisions against ragdolls in the Bullet solver.

FlipFluidWire Example for FLIP Solver dynamics node

This example demonstrates the use of the Flip Solver and the Fluid Force DOP. The Fluid Force DOP is used to apply a drag force on a wire object according to the motions of a flip fluid. The drag force is only applied at locations where fluid exists in the fluid object.

grass

This example simulates grass being pushed down by an RBD object. Fur Objects are used to represent the blades of grass and Wire Objects are used to simulate the motion. When a single Fur Object is used to represent the grass, neighbouring blades of grass will have similar motion. Additional objects with different stiffness values can be used to make the motion less uniform. When "Complex Mode" is enabled, two objects are used to represent the grass. The stiffness of each set of curves can be controlled by adjusting the "Angular Spring Constant" and "Linear Spring Constant" parameters on the corresponding Wire Objects.

FluidGlass Example for Particle Fluid Solver dynamics node

This example demonstrates how to get a smooth fluid stream to pour into a glass.

Down Hill Lava Flow Example for Material shader node

In this file we create a downhill lava flow with crust gathering and hardening at the base of the slope. All of the animation is achieved through the shader itself, and all of the geometry is completely static.

Note

Most of the parameters for the lava material are overridden by point attributes created in the surface nodes.

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.

VolumeNoiseIso Example for Mantra: VEX Volume Procedural shader node

This example shows how to render an isosurface defined by a cvex shader using mantra’s volume rendering capabilities. A noise field is generated by a cvex shader, which is attached to the VEX Volume Procedural. The volume is shaded by finding the surface where the density crosses 0, and then shading using a simple surface shader that shows the normals.

PathAnalysis Example for Find Shortest Path geometry node

This is an advanced example of how to use the FindShortestPath SOP to prefer "central" paths, based on centraily measures computed using FindShortestPath and AttribWrangle. This helps avoid staying too close to walls where avoidable.

Turn on the Display Option > Optimization > Culling > Remove Backfaces to see inside the space more easily. Try visualizing the different centrality measures using the switch node. The same example without considering the centrality of the path is demonstrated in a side branch of the SOP network, in order to see the difference.

FurBall Example for Fur geometry node

This example demonstrates how the Fur SOP builds hair-like curves based on guide curves and skin geometry.

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.

volumecompress Example for Volume Compress geometry node

This example shows how to use the Volume Compress SOP to reduce the memory requirements of volumes without too adversely affecting their appearance.

volumesurface_explicitgrade Example for Volume Surface geometry node

This example shows how to use the Volume Surface SOP to surface an SDF using another volume to specify the triangle sizes.

volumesurface_simple Example for Volume Surface geometry node

This example shows how to use the Volume Surface SOP to surface an SDF using adaptive triangle sizes.

See also

VOP nodes