How to watch voxel value of vector field like velocity in pyro

[riskneutral]

Hello people,

I'm using pyro fx to create flame and need to extract velocity field and other filed. As SideFx onlinehelp says, The Vector Field DOP creates a Vector Field data that can be attached to simulation objects and manipulated by solvers. A Vector Field is an axis-aligned box divided into individual voxels. Each voxel is giving a 3d vector.But how can I watch the value of every voxel at every timeframe?

Many thanks for any help,

RN

[narbuckl]

If your talking about visualizing custom data in dops (i.e. not the default velocity field that the smoke object lets you visualize), you can use a vector field visualization dop node, attach it into the green input of your sop vector field and you can visualize it that way. If your trying to 'extract' the velocity field outside of dops, you can use a blast node with an @vel.* expression, you can use a volume visualization node to view the data as a volume. One thing I like to do to visualize velocity fields in sops is use the volume trail sop with some sourced points and it will show you the flow of your velocity. Otherwise you could scatter points in your velocity field and sample the value to point attributes with a volume sample in a vopsop.

-Nathan

[Macha]

The scatter points method that Nathan suggested is by far the easiest. Vel volumes can have a wide range of values that makes it hard to visualize as density. If you normalize the velocity lengths you can to some extend get an idea of the field if you color vel.x vel.y and vel.z with red green and blue respectively.

A good modification of the points method is to take slices and visualize only them.