Texture Falloff

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

Page: Texture

Group Group – 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 UVW Usecustomuvw – When enabled, uses custom attributes for texture coordinate lookup instead of world position.
Lookup Index Attribute U Lookupindexattr0 – Attribute to use as the index for the U coordinate of the lookup. Only active when Use Custom UVW is enabled.
Lookup Index Attribute V Lookupindexattr1 – Attribute to use as the index for the V coordinate of the lookup. Only active when Use Custom UVW is enabled.
Lookup Index Attribute W Lookupindexattr2 – Attribute to use as the index for the W coordinate of the lookup. Only active when Use Custom UVW is enabled.
Lookup Index Offset Lookupindexoffset – – Offset applied to custom UVW coordinates before sampling. Only active when Use Custom UVW is enabled.
Lookup Index Offset Lookupindexoffset1
Lookup Index Offset Lookupindexoffset2
Lookup Index Offset Lookupindexoffset3
Lookup Index Units Indexunit – – Units for lookup index attribute. Only active when Use Custom UVW is enabled.
Normalized normalized
Pixels pixels
Lookup Channel Lookupchannel – – Which channel or combination of channels to use for falloff values.
Luminance luminance
Red red
Green green
Blue blue
Alpha alpha
RGB Average rgbaverage
RGBA Average average
RGB Maximum rgbmax
RGBA Maximum max
Pixel Centered Sampling Location Pixelcentered – – Enable input remapping to sample pixels centers.
Pixel Centered Sampling Location Pixelcentered1
Pixel Centered Sampling Location Pixelcentered2
Pixel Centered Sampling Location Pixelcentered3
Cyclic Lookup Cyclic – – When enabled, the index wraps so the end connects back to the start, letting the full range map evenly across the cycle.
Cyclic Lookup Cyclic1
Cyclic Lookup Cyclic2
Cyclic Lookup Cyclic3
Input Extend Mode Inputextend – – What happens when the lookup index attribute is outside of the valid range.
Hold hold
Zero zero
Repeat repeat
Mirror mirror
Interpolate Interpolate – When on, the TOP can be interpolated between pixels. When off, the nearest pixel used.
Use Depth Offset Usedepthoffset – Enable using the texture's depth offset for Texture 3D TOPs.
Normalize Sampling Position Normalizesamplepos – Normalizes point positions to 0-1 range based on bounding box before sampling.
Translate T – – Translation offset for texture sampling coordinates.
Translate Tx
Translate Ty
Translate Tz
Rotate R – – Rotation of texture sampling space in degrees.
Rotate Rx
Rotate Ry
Rotate Rz
Scale S – – Scale factor for texture sampling coordinates.
Scale Sx
Scale Sy
Scale Sz
Pivot P – – Pivot point for texture space transformations.
Pivot Px
Pivot Py
Pivot Pz
Uniform Scale Scale – Uniform scaling factor applied to all axes equally.

Page: Falloff

Combine Operation Combineop – Mathematical operation used to combine this falloff with existing falloff values.
Combine Falloff Attribute Combattrscope – Specifies which falloff attribute to combine with when Combine Operation is not set to Set.
Swap Operation Order Swaporder – Reverses the order of operands in the combine operation (A op B becomes B op A).
Combine Strength Combstrength – Blending factor for the combine operation, ranging from 0 (no effect) to 1 (full effect).
Output Falloff Attribute Outputfalloffattr – Name of the attribute where the final falloff values will be stored.
Preview Falloff Previewfalloff – When enabled, visualizes falloff values using a color ramp.
Falloff Ramp Fallofframp – Color ramp preset used for visualizing falloff values when Preview Falloff is enabled.
Open Custom Ramp Opencustumramp – Opens the custom color ramp editor for defining a custom falloff visualization gradient.
Reset Custom Ramp Resetcustomramp – Resets the custom color ramp to its default state.

Page: Noise

Apply Noise Applynoise – When enabled, adds procedural noise to the falloff values for organic variation.
Combine Operation Combineopnoise – How noise values are combined with the base falloff (Add or Multiply).
Type Type – – Noise algorithm type (Perlin, Simplex, etc.).
Perlin 2D (GPU) perlin2d
Perlin 3D (GPU) perlin3d
Perlin 4D (GPU) perlin4d
Simplex 2D (GPU) simplex2d
Simplex 3D (GPU) simplex3d
Simplex 4D (GPU) simplex4d
Seed Seed – Numerical value that initializes the randomization.
Period Period – Period (scale) of the noise field.
Harmonics Harmon – The number of higher frequency components to layer on top of the base frequency. 0 harmonics give the base shape.
Harmonic Spread Spread – The factor by which the frequency of a harmonic increases relative to the previous harmonic.
Harmonic Gain Gain – Amplitude of the Harmonics layered on top of the base frequency.
Amplitude Amp – The noise values amplitude (a scale on the values output).
Exponent Exp – Sets the exponent. The internal value is raised by the power of the exponent.
Offset Offset – Adds an offset to the resulting value.
Transform Order Xordnoise – – Sets the overall transform order for the transformations.
Scale Rotate Translate srt
Scale Translate Rotate str
Rotate Scale Translate rst
Rotate Translate Scale rts
Translate Scale Rotate tsr
Translate Rotate Scale trs
Rotate Order Rordnoise – – Sets the order of the rotations within the overall transform order.
Rx Ry Rz xyz
Rx Rz Ry xzy
Ry Rx Rz yxz
Ry Rz Rx yzx
Rz Rx Ry zxy
Rz Ry Rx zyx
Translate Tnoise – – Translate the points through the noise space.
Translate Tnoisex
Translate Tnoisey
Translate Tnoisez
Rotate Rnoise – – Rotate the points around the corresponding X, Y and Z axes. Angles are given in degrees.
Rotate Rnoisex
Rotate Rnoisey
Rotate Rnoisez
Scale Snoise – – These three fields scale the Source geometry in the three axes.
Scale Snoisex
Scale Snoisey
Scale Snoisez
Pivot Pnoise – – The pivot point for the transform rotates and scales.
Pivot Pnoisex
Pivot Pnoisey
Pivot Pnoisez
Translate 4D T4dnoise – Translates the points through the 4th noise dimension.

Page: Remap

Clamp Clamp – When enabled, constrains falloff values to the 0-1 range.
Fit Fit – Enables remapping of falloff values from an input range to an output range.
Auto Input Min Max Auto – Automatically determines input range from actual min/max falloff values.
Input Min Inputmin – Minimum value of the input range for remapping.
Input Max Inputmax – Maximum value of the input range for remapping.
Output Min Outputmin – Minimum value of the output range for remapping.
Output Max Outputmax – Maximum value of the output range for remapping.
Invert Invert – Reverses the falloff values (1 - value).
Enable Remap Ramp Enableremapramp – Applies a custom curve defined by a ramp to remap the falloff values.
Open Remap Ramp Openremapramp – Opens the ramp editor for defining the custom remapping curve.
Reset Remap Ramp Resetremapramp – Resets the remap ramp editor.
Remap TOP Remaptop – Reference to an external TOP for remap control. When specified, overrides the internal ramp editor.

Page: Common

Bypass Bypass – Pass through the first input to the output unchanged.
Free Extra GPU Memory Freeextragpumem – Free memory that has accumulated when output memory has grown and shrunk.
Render Primitives Renderprimitives – Toggles rendering of POPX Geometry or shows it as point instances only.
SRT / RST Srtrst – Sets the transform order when using POPX Geometry as built-in TouchDesigner instances.

Inputs

Input 0 POP – POPX/POP Geometry
Input 1 TOP – Texture

Outputs

Output 0 POP – POPX_out1