[size=200]FREQUENTLY ASKED QUESTIONS:[/size]
[size=150]Q:[/size] Why should I use FROST over the built-in BlobMesh in 3ds Max?
[size=150]A:[/size] FROST is orders of magnitude faster, more scalable and more controllable than BlobMesh and supports more particle sources.
[size=150]Q:[/size] Why should I use FROST over 3D Aliens’ pWrapper?
[size=150]A:[/size] FROST is several times faster than pWrapper, supports more particle sources, provides more meshing modes and more control over the particle data esp. when used in conjunction with Krakatoa objects and modifiers.
[size=150]Q:[/size] Why should I use FROST over the free Bercon Metaballs for V-Ray?
[size=150]A:[/size] FROST generates actual polygons in both the viewport and the renderer. Thus, it can be integrated into the same modifier pipeline as regular geometry objects and can be rendered in any renderer supporting polygons, not just in V-Ray. It also supports a lot more particle sources.
On the flip side, the V-Ray metaballs can be faster to calculate since no polygon data is being sent to the renderer, and the results can look smoother when compared to the default settings of FROST, althrough it is possible to achieve similar results with the right settings.
The following table shows the particle sources supported by the various 3ds Max Metaball solutions:
[size=150]Q:[/size] Can I control the size of the particles?
[size=150]A:[/size] Yes, there are multiple ways to control the size/influence of the particles. There is a global value that can be used to change all particles at once. There is an option to randomize the particle size based on the particle’s ID or Index. Yet another option allows the direct control of particle size via a custom Radius channel which can be provided by a Krakatoa Channels Modifier or could be stored in a PRT file. And in the case of Particle Flow, the Scale channel will be accepted as a valid Radius channel and will also control the size of the particles.
[size=150]Q:[/size] pWrapper has an option to fade off the Particle size by the Particle Age. Can I do this in FROST?
[size=150]A:[/size] Yes, there is a Scale Radius parameter that can be keyframed freely and synchronized by Time, Age or Life%. It can also be done using a PRT Loader and Krakatoa Channel Modifiers, Particle Flow with a Box #3 DataOp or Particle Flow with a Script Operator.
[size=150]Q:[/size] pWrapper has a built-in Relax option. Does FROST provide the same option?
[size=150]A:[/size] No, the Relax modifier of 3ds Max is very fast and can be applied to the resulting FROST mesh at any level on the stack, including after procedural Volume Select vertex selections to affect only portions of the blob mesh – something that would be impossible with a built-in relax feature. This approach provides support for Vertex Soft-Selections for gradual blending between relaxed and non-related surfaces; relax by texture map; relax by KCM Selection based on any other particle channel, and so on.
[size=150]Q:[/size] pWrapper provides caching of the calculated mesh. Does FROST support anything similar?
[size=150]A:[/size] Not in the current version. FROST supports saving to various formats including a mesh and a level set format, but the corresponding objects for loading the resulting meshes or level sets are currently not part of the FROST package, so the respective saving features have been disabled. Caching could be an option in the future, but given the performance of the current meshing code, there is not much need for such a feature at the moment.
[size=150]Q:[/size] Moving particles can cause topology changes on sub-frames, thus breaking motion blur in renderers like V-Ray. Can FROST deal with this?
[size=150]A:[/size] Yes, FROST provides two interpolation modes – the one behaves as described above and produces a new mesh on each sub-frame, useful for multi-pass motion blur rendering where topology changes do not matter. The other uses the velocities of the particles to deform the mesh on sub-frames and produces plausible motion blur without changing topology within the half-frame interval before and after the frame. This method can be used with V-Ray and similar renderers that expect consistent topology.
[size=150]Q:[/size] The initial mesh quality in the viewport is too low. Why is that?
[size=150]A:[/size] Originally, the default viewport mode was Tetrahedron and the default Radius value was set to 1.0. Early benchmarks demonstrated that using Union Of Spheres with a default Radius of 5.0 produces a much faster preview out of the majority of typical particles systems when using the default scene scale settings. Thus, these values were introduced as the new factory defaults. You can tweak them after the fact or use the Presets Saving / Defaults system of Frost to define your own custom defaults for newly created Frost objects.
[size=150]Q:[/size] I am using a PRT Loader with Playback Graph retiming as the source and Motion Blur is not working correctly in V-Ray. What can I do?
[size=150]A:[/size] The Frame Velocity option of Frost assumes that there is one PRT source per frame and will interpolate vertex positions based on that frame’s velocities to generate consistent topology. But when the source is a PRT Loader with a custom retiming curve to speed up the animation, each sub-frame evaluation of the PRT Loader could cause a different PRT frame to be loaded, in turn forcing an update of the Frost mesh on sub-frames. To avoid this, you must bake the retimed PRT sequence by saving the PRT Loader’s particles to a new PRT file sequence. Then load the retimed PRT files in Frost either via another PRT Loader or through the file loading options of Frost itself and the Frame Interpolation will work as expected. Note that you can add a KCM to the PRT Loader and multiply the Velocity values to produce more or less motion blur without changing the V-Ray Motion Blur beyond the safe Shutter of 0.5 and Offset of 0.0 values.