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This operator provides outputs that represent all the global variables for the volume VOP network type. There are no inputs to this operator.
The Volume VOP operators, such as Gas Field Vex DOP and the Volume VOP SOP, can process multiple volumes simultaneously. Volumes are bound to specific parameters and all bound volumes are available when processing one volume.
Most of the parameters provided refer to the specific volume currently being processed. The exception is Density, which is provided for convenience for simple networks.
Volume VOP Global Variables do not work in cvex shaders.
Position of current voxel.
Value of the
density field at this voxel location.
ix, iy, iz
Voxel indices. For Volumes these ranging from 0..resolution-1. For VDBs, they refer to the absolute location. Use volumepostoindex with the orig to get the lowest value of the ix,iy,iz for the current VDB.
resx, resy, resz
Resolution of the current volume.
The center of the current volume.
The bottom left corner of the current volume.
The size of the current volume.
dPdx, dPdy, dPdz
These vectors store the change in
P that occurs for
each step in the x, y, and z voxel indices.
Position inside the bounding box of the volume. Each coordinate ranges from 0..1.
The global time at which the volume is being evaluated.
The timestep currently being used for simulation or playback.
The current frame being processed, note this can be fractional.
First to Fourth Inputs
These provide a path to the inputs of the Volume VOP SOP. They can be wired to any VOP that takes a file path for geometry to have the node instead use one of the inputs of the SOP.
The following examples include this node.
This example demonstrates how the AttribFromVolume SOP can be used to transfer volume values onto point attributes.
This example shows how to use the Volume Compress SOP to reduce the memory requirements of volumes without too adversely affecting their appearance.
This example shows how to detect the overlapping regions of many incoming volumes procedurally using Volume SOP and Volume Merge SOP.
This example shows how to use the Volume Reduce SOP to compute the barycenter of a 3d object.
This example shows how to use the Volume Resample SOP to increase and decrease the resolution of a volume. It also shows how the different sampling options affect the quality of the resulting volume.
This example shows how to use the Volume Surface SOP to surface an SDF using another volume to specify the triangle sizes.
This example shows how to use the Volume Surface SOP to surface a hierarchy of SDFs using explicit grading.
This example shows how to import multiple volumes into a Volume VOP SOP.