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OpenVDBShape

This operator creates an ISO-Surface based on particle information; which is usually used for representing a fluid surface or any other kind of surface based on a point cloud. This operator is using industry standard OpenVDB offering a fully multi-threaded approach to particle meshing. It is one of the fastest meshers available on the market.

Operator Inputs

ON - (Bool) This input data stream determines whether the operator is considered 'on' or 'off.' You can connect other operators to this input channel such as a Bool Helper to activate/deactivate the whole operator.

Time
 - (Time) This input data stream is used to define the local time for the operator when the user wants to override the default system time.

The remaining input parameters are identical to the UI controls. For more information about the use of an individual parameter check out the descriptions below.

Operator Outputs

This operator has no outputs

 

Rollout Menu

Group - select a particle group that will be used to create a mesh out of the particle cloud.

Include Sub Groups - check this option to use the particle sub groups as well.

Radius Scale - this represents the "search" radius for creating a continuous surface based on the particle cloud. the bigger this radius the more particles will be evaluated and taken into account in creating a surface.

ISO Value - this defines the 'tightness' around the particles of the created surface. Negative values will move the surface closer to the particles (until the surface disappears) larger, positive values will usually create a smoother more loose surface representation of the point cloud.

Filter - before processing of the point cloud a filter can be used to smooth out the result even further. Available filters are:

None - when selected, no filter will be used at all. The original particle positions will; define the surface.
Box - check this option to use a Box filter on the particle cloud
Gaussian - check this option to use a Gaussian filter on the particle cloud
Mean Curve - check this option to use a Mean Curve filter on the particle cloud
Laplacian - check this option to use a Lapace filter on the particle cloud

Iteration - filters have the option to iterate multiple times across the point cloud to create an even smoother result when creating a surface. Use this option to set the amount of iterations.,

Width - defines the area, used to apply the filter. The larger this area the smoother the surface gets.

Adaptivity  - a valuer of 0 turns this function off. Higher positive numbers will create an adaptive mesh resolution that will only show higher mesh density near curvatures and details.

Relax Disoriented - check this option to move particles closer when they seem disoriented in relation to other faces.

Resolution View - lets you set the mesh resolution for the viewport display. The higher this number the finer and more detailed the mesh will be.

Resolution Render - lets you set the mesh resolution for the rendering output. The higher this number the finer and more detailed the mesh will be.

Half Width NBand - controls the width or depth of the voxels 'narrow band' on surface generation. Smaller values may reduce the mesh density and the mesh may also look a little more detailed. However, set it too low the mesh surface may break or disappear. Larger values might create a smoother looking mesh. Most of the time it is not recommended to touch this value.

Important: Do not use excessive values. Higher values will create by the cubic more voxels!

Radius Min/Radius Max - this two controls allow you to exclude or cap the particles that will be used to create the surface. All particles that fall within those two size values will be used to create a surface. Particle sizes outside those two numbers will be ignored by the mesh generation process.

MTD Grain - this value controls the efficiency of multi-threading. A value of 0 turns of multi-threading. It is recommended not to touch this setting unless you know what you are doing. In general, higher Grain numbers will try to create more parallel processes. However, more does not always mean better! Too many processes will create more overhead and might execute slower. You may try playing with this value if you have a massive parallel CPU, in the end you might gain some save some seconds.

Mesh Relax - check this option to activate a post process mesh relaxing function. This is extremely useful for critical high detail situations to get soem extra smooth surfaces.

Smooth - a value of 1.0 will create the maximum of mesh smoothing (relaxing), a vlue of 0 will turn it off.
Iterations - sets the number of times this relaxation is processed over all vertices of the OpenVDB mesh.

Material - lets you select a material to be used for the surface.

Material ID - sets the material ID for the created mesh.

 

Data To Mapping Channel

IRadius Scale - lets you control the influence radius for diffusion effects. This value is a scale factor based on the individual particle radius. Use larger values to smooth out the diffusion effect on the surface of the fluid/object.

UVW - defines the particle Data channel to be used as the UV mapping channel.

Mapping ID - sets vertex color channel ID to store the UVW data

Color - defines the particle Data channel to be used as vertex color.

Mapping ID - sets vertex color channel ID to store color information in the implicit surface.

Vector - defines the particle Data channel to be used as 3 point vector.

Mapping ID - sets vertex color channel ID to store 3 point vector information

Vector 1- defines the particle Data channel to be used as 3 point vector.

Mapping ID - sets vertex color channel ID to store 3 point vector information

Vector 2- defines the particle Data channel to be used as 3 point vector.

Mapping ID - sets vertex color channel ID to store 3 point vector information

Vector 3- defines the particle Data channel to be used as 3 point vector.

Mapping ID - sets vertex color channel ID to store 3 point vector information

Tip:
You can easily use a vector to control three values at once. Vertex Color in a mesh (implicit) allows you to access each component individually from within the material editor. An R component could be used as a diffuse factor, a G component could be controlling the reflectivity and a B component could be controlling the transparency of a material.

 

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