dilate_influence

The dilate influence can be used to keep emitted colors in an aero simulation from going dark over time. It propagates a defined property inside dense regions outward into zero density regions. For example if one adds voxel_color to the source then the voxels outside the emission regions will initially be black. Over time as these regions mix with the dense regions the color can turn black. This influence can be used to extend the color outward a voxel or two from dense regions, such that empty boundary that mixes in always has well defined color. To use this node, plug its output into the influences input of simulate_aero.

Inputs

influence

One may optionally connect an influence field out_influence into this port. For example a mask_influence node could be connected to mask the effect of this influence. Any number of influence fields may be added to the daisy chain to build a complex field.

enable

Turn off to disable the effect. Disabling makes it a pass through node. Note that any other influence fields connected to the influence input port will still be active when this is disabled.

property

The name of the voxel property to propagate into zero density regions.

field_type

This is the data type of the property one is propagating. It should be set to match the type of the named property. For example voxel_fog_density would be float while voxel_velocity would be float3.

voxel_size

This is the distance in worldspace units to extend the voxel property into zero density regions. Values larger than a voxel may extend in a blocky fashion as the extension is only in orthogonal directions. For keeping colors from becoming dark over time a value equivalent to 2 or 3 times the detail size may be needed, especially if the simulation velocity is high. Note that the simulation's detail size is the source fluid_detail_size when the resolution mode is set to absolute. You can connect a ScalarField to vary the effect over space.

density_threshold

Voxels where the voxel_fog_density is below this threshold are considered empty. This value should be small but not zero, because during simulation a small diffusion of density can occur that quickly propagates into regions that otherwise appear to be empty. You can connect a ScalarField to vary the effect over space.

Outputs

out_influence

An output influence object that one can connect to simulation nodes or other influence nodes.