Viewer

Exporting solved data from GPU memory to VDB to re-upload it back into the GPU in its internal format for viewport display, takes a significant amount of time and consumes additional memory.

To compensate for this, a built-in viewer is available, accessible from:

1. The solver node (next to the Reset Simulation button);

2. The plugin shelf;

3. New Pane Tab -> GAZ Viewer.

The viewer can render directly from the memory of the selected simulation device, using either a fast ray-tracing mode or a full path-tracing mode with support for matte and emissive geometry.

Fine-tuning is achieved via an external GAZ Visualize node, which can be quickly created through GAZ View -> Environment -> Create Extended Vis Network.

When playing the timeline in reverse, the viewer displays cached frames, which also can be exported as an MP4 (if caching is enabled via Setup -> DOP Playback Policy -> Save GAZ Viewer Flipbook).

Note

When using the viewer, it is recommended to disable VDB output for the reasons mentioned above.

GAZ Solver -> GAZ View tab

Viewer

In Ray-trace mode, light sources are ignored (currently), but everything else functions properly, including matte objects, it is suitable for real-time emissive (fire, explosions) visualization.

In Path-trace mode, light propagation is computed from the sky, light sources, and polygonal objects with emissive materials, which is suitable for high-albedo volumes (dust, clouds).

Material

Shading is based on the standard absorption + scattering + emission model.

Absorption and scattering are determined by the soot field, while emission is based on the temperature field (using an intensity and a color gradients).

This model fully matches the one in Arnold Standard Volume, for example.

To achieve a similar viewport result, use PyroBakeVolume, where scattering corresponds to smoke color, fire is set up with similarly adjusted intensity and color ramps, and the appropriate mapping range. Fire masking should be enabled,

which roughly corresponds to multiplying the final flame by the square root of density (whereas in a physically correct model, the square root is absent).

Diagnostics

Currently, diagnostics include a logger (available below the viewer window) and a set of five configurable volume slices.

Each slice displays selected solver field data at the plane’s location.

Automatic calculation of the minimum and maximum slice values, followed by gradient fitting, is triggered by pressing the F key in the viewer.