Houdini 20.0 Shelf tools

Smoke Trail shelf tool

Generates a clustered simulation of smoke from an animated object.

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Overview

This tool creates a complex geometry network to generate clustered source geometry for the smoke from points scattered along the object’s animated path. Each cluster of points is simulated in a separate smoke box. Simulating a series of smaller boxes along the path is much more efficient than simulating all smoke in one large box.

How to

To...Do this

Give an animated object a smoke trail

The object should already be animated before you use this tool.

  1. Select an animated object.

  2. On the Pyro shelf, click the Smoke Trail tool.

    The tool creates a Geometry object to generate the smoke source (objectname_sourcepts), a simulation network (if it doesn’t already exist), and a Geometry object to import the results of the simulation back as renderable geometry.

Prevent the smoke from rising

Modify the temperature point attribute in the objectname_sourcepts network before the rasterization loop.

or

Change the buoyancy on the pyrosolver node.

or

In the DOP network, select the source_density_from_ node and set Scale parameter for temperature import (under the Volumes tab) to 0.

Change the smoke density

Modify the density point attribute in the objectname_sourcepts network before the rasterization loop.

or

In the DOP network, select the source_density_from_ node and change the Scale parameter for density import (under the Volumes tab).

Make the smoke dissipate faster or slower

In the DOP network, select the pyrosolver node. Click the Shape tab, then change the Dissipation. Higher values make the smoke dissipate faster.

Apply a material to the smoke

  1. In the material palette, drag one of the materials from under the Volume heading in the tree on the left to the area on the right to create an instance of the material.

    Different materials give different looks to the generated smoke at render time. For example, “Wispy Smoke” looks less dense than “Billowy Smoke”.

  2. In the network editor, at the object level, select the pyro_import node. This node imports the results of the simulation (the generated smoke) to make it a renderable object. This object is where you should apply the material.

  3. In the parameter editor, click the Render tab. Click the chooser icon next to the Material field. Select the material you just created (for example, /mat/basicsmoke) and click Accept.

Shelf tools

Using the shelf

  • Customize the shelf

    How to change the look of the shelf, change and rearrange its contents, and create your own shelf tools.

Technical