Mantra: Image3D Volume Procedural shader

Replaces object’s geometry with a volume primitive read from a 3D texture (.i3d) file.

See also: How to make clouds

Each channel within the texture will be bound to a corresponding vex shader parameter, if it exists.

This is much more efficient than having a large volume in the scene, since the image3D file can be streamed on demand.

If you don’t specify the bounding box for the procedural, the bounding box of the texture map will be used.

Parameters

Main

I3D File

Specifies the file to render.

Accelerator Density Channel

Specifies the channel to be used to bound null regions of the volume.

IFD Bounds

Bounding Box

The bounding box controls let you specify a bounding box for the referenced geometry. Only when this bounding box is “on screen” will mantra load the referenced geometry. You can set Bounding box to No bounding box required, in which case mantra will always load the references geometry regardless. You can also specify the bounding box by referencing the SOP’s bounding box in the SOP Bounds parameter.

SOP Bounds

The geometry whose bounding box you want to reference.

Min Bounds

The minimum bounding box dimensions, when setting explicit bounds.

Max Bounds

The maximum bounding box dimensions, when setting explicit bounds.

For more information on .i3d files, see the Image3d Files help page.

Usages in other examples

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