Page History

Step % | rendstep – Specifies the ray marching step of the camera rays as a percentage of the cell size. As the renderer traces rays through the Simulator, this value controls how often to read information from the grid. If this value is more than 100, some cells will start getting skipped and artifacts may appear. Usually you don't need to lower this below 90%, unless you use render curves or texture maps for the Fire or Smoke opacity or color - in these cases you might need to lower the step in order to capture the details which are smaller than a voxel, otherwise these details will either be skipped or will render very noisy. However, decreasing the step will make the render slower. This parameter is used when Mode is set to Volumetric, Volumetric Geometry, Volumetric Heat Haze or Isosurface. See the Step % example below.

Shadow Step % | rendshadstep – Specifies the ray marching step of the rays used to evaluate the lighting (shadow rays) as a percentage of the cell size. Usually, this value can be higher than Step %, as generally shadows will not need so much detail. Increasing the Shadow Step % will also speed up rendering performance, particularly with dome and area lights.

Border Fade | borderFade – Makes the content near the grid's boundaries more transparent to prevent sharp edges from being rendered. This parameter controls how far from the boundaries the transparent effect should start, in scene units.

Heat Haze | heathaze, hhfactor – Traces the ray changing direction according to the gradient of the Surface channel. A value of 1 corresponds approximately to the normal heat haze in the air caused by the temperature. If smoke or another channel is selected as the source, a larger value might be necessary to achieve a visible result. A value of 0 produces no heat haze. This parameter is available only when Mode is set to Volumetric Heat Haze. See the Heat Haze example below.

Sampler Type | sampler – Determines the blending method between adjacent grid voxels. Used to balance between rendering speed and quality. This parameter is used when Mode is set to Volumetric, Volumetric Geometry, Volumetric Heat Haze and Isosurface modes.

Box – Displays voxels as cubes. There is no blending between neighbor voxels. This is the fastest mode.
Linear – Linear blending occurs between neighbor voxels to smooth out the fluid's look. Sometimes this mode may unveil the grid-like structure of the fluid. Up to 20-30% faster than the Spherical option.
Spherical – Uses special weight-based sampling for the smoothest looking fluid. With increasing resolution, the visual advantage of this method over the Linear method becomes less noticeable.

Invert Cutter | invgizmo – When enabled, rendering will occur only outside of the render cutter. This is not the same as a cutter with inverted geometry because any rays that do not intersect the cutter will be shaded as well.