POPX

Texture Falloff

v1.3.0
Falloffs

Summary

The Texture Falloff applies falloff values by sampling 2D or 3D textures (TOP) using point positions or custom attributes as UVW coordinates. This allows for highly customizable falloff patterns driven by images, procedural textures, or animated content.

Supports various lookup channels (luminance, RGB, alpha), multiple extend modes (repeat, mirror, hold, zero), and interpolation options. Transform controls allow you to translate, rotate, and scale the sampling space, with optional normalization for consistent results regardless of geometry bounds.

The resulting falloff values can be combined with existing falloff attributes, enhanced with procedural noise, remapped with custom curves, and previewed with color ramps. This makes Texture Falloff ideal for creating complex, art-directable patterns by painting falloff maps in external tools or using TouchDesigner's procedural generation capabilities.

Parameters

GroupGroup
If there are input groups, specifying a group name in this field will cause this POPX to act only upon the group specified.
Texture (TOP)Top
TOP to use for lookup.
Use Custom UVWUsecustomuvw
When enabled, uses custom attributes for texture coordinate lookup instead of world position.
Lookup Index Attribute ULookupindexattr0
Attribute to use as the index for the U coordinate of the lookup. Only active when Use Custom UVW is enabled.
Lookup Index Attribute VLookupindexattr1
Attribute to use as the index for the V coordinate of the lookup. Only active when Use Custom UVW is enabled.
Lookup Index Attribute WLookupindexattr2
Attribute to use as the index for the W coordinate of the lookup. Only active when Use Custom UVW is enabled.
Lookup Index OffsetLookupindexoffset
Offset applied to custom UVW coordinates before sampling. Only active when Use Custom UVW is enabled.
Lookup Index OffsetLookupindexoffset1Lookup Index OffsetLookupindexoffset2Lookup Index OffsetLookupindexoffset3
Lookup Index UnitsIndexunit
Units for lookup index attribute. Only active when Use Custom UVW is enabled.
NormalizednormalizedPixelspixels
Lookup ChannelLookupchannel
Which channel or combination of channels to use for falloff values.
LuminanceluminanceRedredGreengreenBlueblueAlphaalphaRGB AveragergbaverageRGBA AverageaverageRGB MaximumrgbmaxRGBA Maximummax
Pixel Centered Sampling LocationPixelcentered
Enable input remapping to sample pixels centers.
Pixel Centered Sampling LocationPixelcentered1Pixel Centered Sampling LocationPixelcentered2Pixel Centered Sampling LocationPixelcentered3
Cyclic LookupCyclic
When enabled, the index wraps so the end connects back to the start, letting the full range map evenly across the cycle.
Cyclic LookupCyclic1Cyclic LookupCyclic2Cyclic LookupCyclic3
Input Extend ModeInputextend
What happens when the lookup index attribute is outside of the valid range.
HoldholdZerozeroRepeatrepeatMirrormirror
InterpolateInterpolate
When on, the TOP can be interpolated between pixels. When off, the nearest pixel used.
Use Depth OffsetUsedepthoffset
Enable using the texture's depth offset for Texture 3D TOPs.
Normalize Sampling PositionNormalizesamplepos
Normalizes point positions to 0-1 range based on bounding box before sampling.
TranslateT
Translation offset for texture sampling coordinates.
TranslateTxTranslateTyTranslateTz
RotateR
Rotation of texture sampling space in degrees.
RotateRxRotateRyRotateRz
ScaleS
Scale factor for texture sampling coordinates.
ScaleSxScaleSyScaleSz
PivotP
Pivot point for texture space transformations.
PivotPxPivotPyPivotPz
Uniform ScaleScale
Uniform scaling factor applied to all axes equally.
Combine OperationCombineop
Mathematical operation used to combine this falloff with existing falloff values.
Combine Falloff AttributeCombattrscope
Specifies which falloff attribute to combine with when Combine Operation is not set to Set.
Swap Operation OrderSwaporder
Reverses the order of operands in the combine operation (A op B becomes B op A).
Combine StrengthCombstrength
Blending factor for the combine operation, ranging from 0 (no effect) to 1 (full effect).
Output Falloff AttributeOutputfalloffattr
Name of the attribute where the final falloff values will be stored.
Preview FalloffPreviewfalloff
When enabled, visualizes falloff values using a color ramp.
Falloff RampFallofframp
Color ramp preset used for visualizing falloff values when Preview Falloff is enabled.
Open Custom Ramp EditorOpencustumrampeditor
Opens the custom color ramp editor for defining a custom falloff visualization gradient.
Reset Custom RampResetcustomramp
Resets the custom color ramp to its default state.
Apply NoiseApplynoise
When enabled, adds procedural noise to the falloff values for organic variation.
Combine OperationCombineopnoise
How noise values are combined with the base falloff (Add or Multiply).
TypeType
Noise algorithm type (Perlin, Simplex, etc.).
Perlin 2D (GPU)perlin2dPerlin 3D (GPU)perlin3dPerlin 4D (GPU)perlin4dSimplex 2D (GPU)simplex2dSimplex 3D (GPU)simplex3dSimplex 4D (GPU)simplex4d
SeedSeed
Numerical value that initializes the randomization.
PeriodPeriod
Period (scale) of the noise field.
HarmonicsHarmon
The number of higher frequency components to layer on top of the base frequency. 0 harmonics give the base shape.
Harmonic SpreadSpread
The factor by which the frequency of a harmonic increases relative to the previous harmonic.
Harmonic GainGain
Amplitude of the Harmonics layered on top of the base frequency.
AmplitudeAmp
The noise values amplitude (a scale on the values output).
ExponentExp
Sets the exponent. The internal value is raised by the power of the exponent.
OffsetOffset
Adds an offset to the resulting value.
Transform OrderXordnoise
Sets the overall transform order for the transformations.
Scale Rotate TranslatesrtScale Translate RotatestrRotate Scale TranslaterstRotate Translate ScalertsTranslate Scale RotatetsrTranslate Rotate Scaletrs
Rotate OrderRordnoise
Sets the order of the rotations within the overall transform order.
Rx Ry RzxyzRx Rz RyxzyRy Rx RzyxzRy Rz RxyzxRz Rx RyzxyRz Ry Rxzyx
TranslateTnoise
Translate the points through the noise space.
TranslateTnoisexTranslateTnoiseyTranslateTnoisez
RotateRnoise
Rotate the points around the corresponding X, Y and Z axes. Angles are given in degrees.
RotateRnoisexRotateRnoiseyRotateRnoisez
ScaleSnoise
These three fields scale the Source geometry in the three axes.
ScaleSnoisexScaleSnoiseyScaleSnoisez
PivotPnoise
The pivot point for the transform rotates and scales.
PivotPnoisexPivotPnoiseyPivotPnoisez
Translate 4DT4dnoise
Translates the points through the 4th noise dimension.
Enable RemapRemap
Enables remapping controls for adjusting falloff value range and distribution.
ClampClamp
When enabled, constrains falloff values to the 0-1 range.
FitFit
Enables remapping of falloff values from an input range to an output range.
Auto Input Min MaxAuto
Automatically determines input range from actual min/max falloff values.
Input MinInputmin
Minimum value of the input range for remapping.
Input MaxInputmax
Maximum value of the input range for remapping.
Output MinOutputmin
Minimum value of the output range for remapping.
Output MaxOutputmax
Maximum value of the output range for remapping.
InvertInvert
Reverses the falloff values (1 - value).
Enable Ramp RemapEnablerampremap
Applies a custom curve defined by a ramp to remap the falloff values.
Open Ramp EditorOpenrampeditor
Opens the ramp editor for defining the custom remapping curve.
Reset RampResetramp
Resets the remap ramp editor.
Custom Ramp TOPCustomramptop
Reference to an external TOP for remap control. When specified, overrides the internal ramp editor.
BypassBypass
Pass through the first input to the output unchanged.
Free Extra GPU MemoryFreeextragpumem
Free memory that has accumulated when output memory has grown and shrunk.
Render PrimitivesRenderprimitives
Toggles rendering of POPX Geometry or shows it as point instances only.
Convert to Point PrimitivesConverttoptprim
Converts points to primitive points when Render Primitives is toggled off.
SRT / RSTSrtrst
Sets the transform order when using POPX Geometry as built-in TouchDesigner instances.

Inputs

Input 0POP
POPX/POP Geometry
Input 1TOP
Texture

Outputs

Output 0POP
POPX_out1