Having Vellum simulations work with other types of simulations can require some creativity. The multisolver didn’t work with the Vellum solver. I started tinkering with different ways to mix the Vellum solver with a simple RBD simulation setup and came up with a multiple phase workflow to create a more realistic Vellum cloth dynamics with the RBD simulation.

Normals are vectors in computer graphics that define the exterior surface of a geometry and the direction the surface is facing. Normals may also be called “Surface Normals”, but usually are referred as “normals”, are used in 3D applications to help render the polygon on the screen by distinguishing the front and back side of each primitive.

Destruction simulation Houdini Project example files available for download

Outlining geometry with unshared edges. Explanation of how Houdini references edges using points.

Bullet Solver vs RBD Solver, comparison between the two and how to choose between the two. The Rigid Body solver has the option to choose between using the Bullet solver engine or RBD solver engine to calculate the dynamics of the simulation.

So what happens if a color is assigned to the points instead of the primitives? What is the difference between assigning color to points versus assigning color to primitives? Sometimes we experience color bleeding onto other primitives of the geometry, this article explains why.

Demonstration of different types of Vellum sims, along with corresponding Houdini files.

In this post, I’ll demonstrate how to delay the effect for a simulation inside the SOP Solver. This technique can be used for any other simulation in Houdini and doesn’t have to be limited to the SOP Solver.

Houdini expressions are functions available to help you calculate values in the parameters of the nodes. You may have seen $HIPNAME which returns the name of the current hip file. Or the centroid one that I use most often for procedural modeling, $CEX $CEY $CEZ, which returns the centroid vector component.

Using a simple technique to produce Disintegration and Growth effects in Houdini. I then add a variation at the end of the effect to generate a variation of the disintegration effect.

How to generate texture maps for terrains generated from Height Fields in Houdini

If you want something to grow over time or maybe shrink over time, SOP Solvers make it easy. SOP Solvers are perfect for animations where you have an object evolving over time, from frame to frame.

Building upon that collision detection, we can also use the SDF to deform the object upon the collision. Using the SDF value and some math, the grid can be deformed to create footprints stamped on by the Torus.

SDF is short for signed distance field and describes the interior volume of an object. How thick an object is from the middle to the surface? How deep does the cylinder extend? From any point inside an object, using the SDF, it is possible to easily grab the distance to the surface of the object in order to know the depth.

Step by step mathematical explanation of the Sine Wave function and how it’s used in defining motion. Increasing the frequency and increasing the amplitude and flipping the entire curve function.

Javascript vs Houdini. Demo of Javascript code of a simple 2D Version of a Houdini Foreach Loop scene that eats away at a cube. This is a quick demonstration of how coding line by line is different from the nodes in Houdini, but similar because they are derived from the same concepts.

I demonstrate how to use a procedural workflow to create a bottle geometry from scratch. This project finishes off from the previous project and makes it more complete by hollowing out the interior of the bottle geometry and adds thickness to the edges. And also still using a procedural workflow.

Procedural Modeling has infinite possible ways of doing things, and the way Houdini does its point number assignment makes it very convenient to write VEX code to automate things. Using VEX into your procedural modeling workflow is a huge advantage.

This post will go over some tips on how to export the Height Field terrain as an HDA (Houdini Digital Asset) and import it into Unreal Engine as a playable environment or game asset.

Houdini’s Height Fields provides a simple and fast way of building complex landscape geometry, but what if I wanted to hull out areas in the terrain to make a tunnel? Cave? Secret underground path for a game?