GradientTool

Important

Gradient atlases that keep a texture baked
Author colour stops, get a Texture2D that is always current
And its FREE!

Note

A gradient is an asset you can edit, not a PNG you re-export
Every edit rewrites the texture, so materials never sample a stale ramp
Pack many gradients into one asset and address them by name in the material graph
Four blend spaces, so saturated hues stop going muddy in the middle

Tip

Editor-only tooling; the baked texture is an ordinary Texture2D at runtime
Tested with UE5.8+

Caution

GradientTool is currently in beta

How to Use

Right click in the Content Browser and pick Texture ▸ Gradient.

You get two assets side by side:

Asset	What it is
GR_MyGradient	The gradient atlas. Double click to edit it.
T_MyGradient	The baked Texture2D. One row per gradient.

Point a Sample Gradient node at GR_MyGradient, pick a gradient by name, and feed it a Time. Or drop T_MyGradient straight into a Texture Sample if you only have one gradient. Edit the gradient and everything updates underneath, including any open material editor.

Example Material

Add a Sample Gradient to your material graph. Assign your gradient.

Note

This assigned gradient will determine which enum names get populated from the gradient asset - these cannot be changed in the material instance, they remain an index into the gradient array.

Add a Texture Object Parameter. Assign the texture matching the assigned gradient, the sampler type will auto change to Linear Color. Connect it to Sample Gradient::Atlas.

Add a Scalar Parameter. Assign the Control Type as Enumeration, and assign the gradient to this also.

This is the resulting material instance:

Editing

Input	Does
Left click the bar	Add a stop at that position, in the colour already there
Left drag a stop	Move it
Double click a stop	Open the colour picker
Middle click a stop	Delete it
Right click a stop	Colour, interpolation, delete
Delete	Delete the selected stop

A gradient always keeps at least two stops. Every edit is transacted, so Ctrl+Z works throughout. The toolbar has Add, Reverse, Distribute (space stops evenly), and Rebuild; Reverse and Distribute act on the selected gradient.

Features

Atlases

An asset holds any number of gradients, each baking to one row of the texture. Add and remove them from the toolbar, rename them in the box beside each bar, and reorder them from the Gradients array in the Details panel. Names are kept unique because material nodes address a row by name.

Material graph

Node	Gives you
Sample Gradient	RGB / R / G / B / A / RGBA read out of the named gradient
Gradient Coordinate	The UV (and just the V) that reads the named gradient, for a texture sample you build yourself

Both take the atlas asset and a gradient name, and a Time input for the position along the ramp. Time 0 and 1 land exactly on the first and last texel centres, so a sample matches Evaluate.

Driving it from a material instance

Both nodes have two override inputs. Leave them unconnected and the node uses the asset and name set on it; connect them and instances take over.

Input	Feed it	Instance gets
Atlas	a Texture Object Parameter defaulted to T_MyGradient	an atlas picker
Row	a Scalar Parameter	a gradient picker, see below

To pick by gradient name rather than row number, set that Scalar Parameter's Control Type to Enumeration and its Enumeration to your GR_MyGradient asset. A gradient asset is a material enumeration of its own gradient names, so the instance shows a dropdown of them.

Both have to be stock parameter nodes. The material instance editor only displays parameters whose expression is one of the engine's own parameter classes, so a plugin node cannot be one itself.

The row's V is derived from the live texture height, so adding gradients does not disturb materials that are already compiled. Renaming or reordering does change which row a name resolves to; loaded materials are recompiled for you, but a material that was closed at the time picks the change up the next time it is translated.

Interpolation

Set per stop, describing how the gradient reaches that stop from the one before it.

Mode	Behaviour
Linear	Straight interpolation
Constant	Hold the previous colour, then jump
Ease	Smoothstep in and out
Cubic	Catmull-Rom through the neighbouring stops

Blend Space

Set per gradient. This is the difference between a gradient that looks right and one that goes grey through the middle.

Space	Blue → yellow midpoint
Linear	Physically correct, and a flat mid grey
sRGB	Matches how most DCC tools draw gradients
HSV	Shortest-arc hue, saturation preserved across the sweep
OkLab	Perceptually uniform, even lightness ramp

Alpha always blends linearly regardless of the space.

Format

Format	Source	Compression
HDR	RGBA16F	TC_HDR, holds values outside 0-1
LDR	BGRA8	TC_VectorDisplacementmap, a quarter the memory, clamped

Texture width is configurable (default 256) and applies to every gradient. The baked texture is one pixel tall per gradient, uncompressed, non-sRGB, no mips, clamped on both axes, in the ColorLookupTable group. Those settings are owned by the bake and are not editable on the texture.

Blueprint

UGradientAsset::Evaluate(FName GradientName, float Time) returns the colour at a position without sampling the texture, and works in a cooked build. EvaluateByIndex, IndexOfGradient, GetGradientNames and GetGradientV are exposed alongside it, and the gradient array itself is BlueprintReadWrite.

Companion Texture

The gradient owns its texture rather than being one. UTexture2D is declared MinimalAPI with unexported virtuals, so no plugin can subclass it without modifying the engine, and this plugin does not.

The texture is created beside the gradient and written to disk immediately, so the gradient's reference to it never dangles.

• Rename or move a gradient and its texture follows.
• Duplicate a gradient and the copy bakes its own texture, named after the copy. The original's texture is left alone.
• Delete a gradient and the texture stays, because materials may still be using it. Delete it yourself if you want it gone.
• Delete the texture and the gradient rebuilds a new one the next time it loads.

Changelog

1.1.0

• Atlases: an asset now holds any number of named gradients, one per row of the texture
• Added the Sample Gradient and Gradient Coordinate material nodes, with Atlas and Row inputs so material instances can override the atlas and the gradient
• A gradient asset is a material enumeration of its gradient names, so an Enumeration scalar parameter offers those names in a material instance
• Evaluate now takes a gradient name; assets saved by 1.0.0 migrate into a single gradient on load

1.0.0

• Initial Release