Unleash the Power of houdini:Transforming helix vex velocity To smoke

https://www.patreon.com/posts/unleash-power-of-90020419

Creating a tornado vortex in a VEX context and applying a velocity field to a smoke simulation typically involves using a 3D computer graphics software or framework like Houdini. VEX (Vector Expression) is a scripting language used in Houdini for customizing and manipulating various aspects of simulations and geometry. Below, I'll provide a high-level overview of how you can achieve this effect:

1. Setting up the Scene:Open Houdini and create a new project. Set up a new scene with the desired resolution, frame range, and frame rate. Create or import the geometry that will serve as the tornado base or funnel. You can use a simple cone or create a more complex shape.
2. Creating the Tornado Vortex:To create the tornado vortex, you'll use VEX scripting within a Geometry SOP (Surface Operator). Select your tornado geometry. Go to the Geometry Spreadsheet and click on the "Add VEX" button to create a new VEX Wrangle. In the VEX Wrangle, you can write custom code to define the tornado vortex. For example, you can use a combination of trigonometric functions to create a rotating motion. The VEX code might look something like this (this is a simplified example): c

• float radius = 2.0; // Adjust the tornado radius float speed = 0.5; // Adjust the rotation speed float angle = @Time speed; float x = radius cos(angle); float y = radius * sin(angle); @P.xz += set(x, y);This code creates a rotating motion around the Y-axis, which will resemble the tornado vortex.
• Creating a Velocity Field:To apply a velocity field to your smoke simulation, you can create a Volume VOP network. Inside the Volume VOP network, create a VEX Volume Wrangle. Write custom VEX code to define the velocity field. This code will typically use the volume's position and other attributes to determine the velocity at each voxel. You can also use various noise functions and turbulence to give the tornado a more natural and chaotic motion. Here's a simplified example of VEX code for creating a velocity field: c

1. vector pos = @P; vector velocity = set(0, 0, 1); // Adjust the initial velocity // Add turbulence or other effects here @vel = velocity;
2. Applying the Velocity Field to Smoke Simulation:Create a smoke simulation using Houdini's Smoke Solver or Pyro Solver. In the simulation's DOP network, add a "Volume Source" or similar node to introduce your velocity field. Connect the output of the Velocity Field VOP network to the "Source Volume" input of the "Volume Source" node. Adjust the simulation settings, such as density and temperature, to achieve the desired smoke behavior.
3. Rendering:Set up your render settings and materials for the smoke and tornado geometry. Render the animation to see the tornado vortex with the applied smoke simulation and velocity field.

Remember that creating realistic tornado effects can be quite complex, and you may need to refine and iterate on your setup to achieve the desired results. Additionally, the specific steps and nodes in Houdini may vary depending on the version you are using, so consult the documentation for your particular version for more detailed instructions.