Parameters
Smoke Intensity
This is an overall brightener/dimmer for the smoke color.
Use Smoke Color
If this toggle is off, the smoke color is ignored. If both Point Color and Smoke Color are off, the default color is white.
Smoke Color
This is the color of the smoke.
Use Point Color
If this toggle is on, the smoke color is multiplied by any point color. If both Point Color and Smoke Color are off, the default color is white.
Density
Smoke Density
The overall density of the smoke. Higher values are more opaque smoke that reflects light faster.
Shadow Density
This is the same as Smoke Density but is used in the shadow pass. This controls how much light the smoke will block.
Receive Shadows
If this toggle is on, the smoke tests for light visibility. Enabling shadows also enables self-shadowing.
Note
For performance reasons, it is recommended to use Shadow Maps for shadowed smoke.
Illuminance Angle
This is the angle of the cone, in which the smoke will test for shadows.
Bias
The cut off point for the depth field. Any voxels with a depth higher than this cutoff will be given the full smoke density, any voxels with less than this will get 0. Normally signed distance fields have the inside/outside cut off at 0, but mantra clips 0 regions of the volume, so for greater accuracy it is useful to bias the smoke values by at least one voxel diameter. Note that the same value as the bias needs to be added to the source depth field.
Depth
Depth Field
The name of the volume to use as the depth field.
The ramps use the range from bias to bias+max depth. If your source depth field is a signed distance field, you will have to invert and bias it, ie -$V+0.1 to apply a bias of 0.1 with a Volume Mix SOP. This is because signed distance fields use negative values for inside but Mantra will not render negative voxels to speed up rendering.
Map Depth to Density Color
The depth into the liquid is mapped to this color and then multiplied with the smoke color.
Map Depth to Density Opacity
Depth is mapped with this ramp to scale the final opacity of the smoke. This value is multiplied by the Smoke Density value.
See also |