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Global Variables VOP node

Provides outputs that represent all the global variables for the current VOP network type.

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This operator provides outputs that represent all the global variables for the current VOP network type. There are no inputs to this operator.

The variables available from this operator will almost always include all of the input variables provided in the Output Variables operator. The difference between these two operators is that the Output Variables operator only provides inputs for those global variables that can be changed.

Every VOP network type has a set of global variables associated with it. These are the variables inherent to the VEX context that the VOP network operates in. For shading contexts (such as Surface and Displacement) these will be variables like the position of the point on the geometry being shaded (P), or the normal of the surface at the point being shaded (N). For SOP or POP Operator networks, these variables include the position of the point being manipulated (P), and the point number of the point being manipulated (ptnum).

Parameters

Context Type

Specifies the shader context in which the node is active. The shader context can be Surface, Fog, Light, or Displacement.

A Material Shader Builder SHOP can contain several shaders, each defined by a portion of the VOP network the builder SHOP contains. There will be nodes for several shader context types inside. For example, surface and displacement to define a material that assigns color and perturbs the surface geometry.

Other SHOPs, such as Surface Shader Builder or Displacement Shader Builder contain only one type of context. The VOP nodes inside can specify only that context type, so this parameter will be disabled.

Output A Single Variable

When enabled, it shrinks the number of outputs to one and outputs only the global variable chosen from the menu below. This option is very useful when the operator is part of a subnetwork that needs to be accessed by different contexts.

Variable Name

Menu of all available global variables. It works in conjunction with the toggle above it.

Inputs

None.

Outputs

The list of available outputs depends on the current VOP network type. The number of outputs depends on whether Output A Single Variable is enabled.

When found in a VEX Surface SHOP Type network, Outputs include the following.

Cf

Surface Color.

Of

Surface Opacity.

Af

Surface Alpha.

P

Surface Position.

Pz

Surface Depth.

I

Direction from Eye (camera) to Surface.

dPds, dPdt

Directions or Derivatives of surface.

N

Surface Normal.

Ng

Surface Geometric Normal.

Eye

Position of Eye (camera).

s, t

Parametric s and t coordinate (u, v).

Time

Shading Time.

dPdz

Change in Position with depth.

SID

Sample Identifier. A sample id to be used with the nextsample() VEX function to generate consistent random samples that don’t change when re-rendering or between frames.

Examples

The following examples include this node.

Street Crowd Example Example for Crowd Solver dynamics node

DensityViscosity Example for FLIP Solver dynamics node

FlipColorMix Example for FLIP Solver dynamics node

FlipColumn Example for FLIP Solver dynamics node

SpinningFlipCollision Example for FLIP Solver dynamics node

PaintedGrog Example for Fluid Object dynamics node

DiffuseSmoke Example for Gas Diffuse dynamics node

TimelessGas Example for Gas Particle to Field dynamics node

grass

PopFlow Example for Particle Fluid Solver dynamics node

CurveForce Example for POP Curve Force dynamics node

2dfluid Example for Smoke Object dynamics node

BreakWire Example for Wire Solver dynamics node

RainbowGeometryLight

IndirectLightBox Example for Indirect Light object node

RampReference

Down Hill Lava Flow Example for Material shader node

FirePit Example for Material shader node

StyleDisplacement Example for Material shader node

VolumeNoiseIso Example for Mantra: VEX Volume Procedural shader node

BlendAttr Example for Attribute Composite geometry node

RandomMaterial Example for Attribute String Edit geometry node

FluffyTorus Example for Bake Volume geometry node

PathAnalysis Example for Find Shortest Path geometry node

repeatsmooth

FurBallWorkflow Example for Fur geometry node

FurPipelineExample Example for Fur geometry node

PaintPoints Example for Paint geometry node

AlphaOmega Example for Points from Volume geometry node

UnpackWithStyle Example for Unpack geometry node

volumeanalysis_grad Example for Volume Analysis geometry node

volumesurface_explicitgrade Example for Volume Surface geometry node

volumesurface_simple Example for Volume Surface geometry node

pscaleVOPSOP Example for Add Attribute VOP node

GroupPainted Example for Add Point to Group VOP node

VOPpointgroup Example for Add Point to Group VOP node

WornMetal Example for Curvature VOP node

ST_Colour

CrinkleSphere Example for Inline Code VOP node

IntersectGrid Example for Intersect VOP node

SimpleMetaImport Example for Meta-Loop Import VOP node

RampParameter Example for Parameter VOP node

PointCloudIterateAverage Example for Point Cloud Iterate VOP node

PointCloudWrite Example for Point Cloud Write VOP node

RaytraceVopShader Example for Ray Trace VOP node

SensorDeform Example for Sensor Panorama Create VOP node

ParticleVolumeCollision Example for Volume Sample VOP node

See also

VOP nodes