What's New in Simulation and Effects

Bifröst

The Bifrost menu is now available in the FX menu set.

Note: Bifröst in Maya 2016 includes a number of feature additions and enhancements that may affect simulations created in earlier versions. Scenes saved from earlier versions may produce different results in Maya 2016.

Bifröst Aero

A new aerodynamic FLIP solver in Bifröst lets you create simulated fire, smoke, cloud, and fog effects. Bifröst Aero includes independent control of the simulated FLIP particle density and the rendered particle density. This means you can simulate at lower resolutions while rendering higher resolution versions of your effect.

See Work with Bifröst Aero.

Bifröst foam

New foam particles let you add bubbles, froth, and spray to churning and fast moving liquids. Use Bifröst foam to add realism to breaking waves and other types of splash effects. With Camera Adaptivity, you can emit foam particles based on the distance from a camera. This lets you create high resolution simulations close to the camera where the detail is needed, while lowering the number of foam particles or eliminating them in other areas of the scene. You can also use the camera's frustum as a clipping region for foam emission.

Guided liquid simulations

New guided simulation workflows let you drive the behavior of liquids using a cached simulation or an animated mesh object. With a guided simulation, you can create and cache a full-depth low resolution liquid, and then use it to guide a high resolution simulation on the liquid's surface. Use guided simulation for such effects as carefully art directed hero waves. You can also perform multiple iterations at high resolution while retaining the basic look and motion of the underlying guiding simulation.

Adaptivity

New adaptivity features have been integrated into the Bifröst liquid solver.

  • Spatial: A new Spatial adaptivity feature lets you maintain high resolutions in your liquid where the detail is needed, such as areas where the liquid is moving and along collision boundaries. At the same time, the solver reduces resolution where the liquid is static, such as in its interior regions.

    Enabling Spatial adaptivity reduces memory use and cache file size, while maintaining the realistic look of liquid simulations.

  • Time Stepping: You can now control time stepping for liquid simulations using Time Step Adaptivity attributes.

    See Bifrost Adaptivity attributes.

Kill volumes

New kill volumes let you isolate Bifröst liquid and aero emission to the bounding box regions of a polygon object. Regions outside of the kill volume do not emit particles.

See Work with Bifröst Clipping and Kill Volume meshes.

New Bifröst liquid attributes

  • Surface Tension

    A new Surface Tension attribute sets a fast approximation value for liquid surface tension. The default value of 0.072 generates the appropriate surface tension for water in N/m, assuming that the scene has been modeled to a scale of 1 grid unit = 1 meter.

    See Bifrost Surface Tension attributes.

  • Viscosity

    Use the new Viscosity attributes to smooth liquid flow in your simulations.

    See Bifrost Viscosity attributes.

Tile View

A new Tile View preview uses color mapping to display the range of voxel resolutions in your simulation. This lets you see which parts of the simulation are being computed at different levels of resolution.

Use the Tile View controls to isolate the preview to specific areas of interest. This is useful for visualizing what is happening in the interior regions of the simulation for diagnostic purposes, especially when using adaptive solve.

You can access the Tile View controls from the bifrostShape Attribute Editor. See Preview Bifröst voxel resolutions using Tile View.

Performance improvements

In addition to Adaptivity, refinements have been made to the FLIP liquid solver to maximize CPU usage and reduce memory. Object voxelization has also been improved to work with a wider variety of shapes.

Better opacity

Particles and voxels have better opacity sorting and deformation, especially when the Hardware Renderer 2.0 Transparency Algorithm is set to Depth Peeling.

nDynamics

Maya soft bodies use nDynamics

You can now solve Maya soft body simulations using Nucleus dynamics. With its addition to nDynamics, soft bodies now interact with Nucleus objects, such as nParticles and nCloth. Use nConstatints with soft bodies and save soft body simulations to nCaches.