Houdini 20.0

Color visualizer

Visualizes attributes by displaying them as color.

See visualizers for more information.


Color Type

Determines the main method for coloring the displayed geometry.

Attribute as is

Displays attribute values as RGB color values.

This only works properly with floating point attribute types. If the attribute has only one component, it is used as the red channel. If it has two components, they are used as red and green.

Ramped attribute

Looks up attribute values on a color ramp and colors the geometry with the corresponding color.


Colors the geometry with a single color. This may be useful for tracking a certain piece of geometry by giving it a bright color when the visualizer is on.


Colors each element of the geometry with a random color.

Random from attribute

Colors attribute values randomly. Attributes with the similar values will have the same color. You can set how different values must be to be colored differently with the Value separation parameter.

Polygon vertex count

Colors triangles, quads, and n-gons differently. This makes it easy to find stray n-gons, or find non-tris when you need only tris.

Texture distortion

Tint faces based on how much the texture is being stretched or squashed in that area.


Whether to visualize a point, primitive, vertex, or detail attribute. This also controls whether the color will be applied to points, vertices, or primitives.

Attribute as is


Name of the attribute to visualize.

Ramped attribute


Name of the attribute to visualize.


To map attribute values onto the ramp, Houdini needs to know the full range of possible values so it can scale that range onto the range of the ramp.


Looks at the actual values of the attribute in the visualized geometry and picks the minimum and maximum.

Min and Max

Allows you to manually specify min and max values. This can be useful when there’s a “natural” range of values larger than what’s currently in the geometry. You can also use a narrower range than what’s currently in the geometry as a way of highlighting values outside the range (see the Out of range values paramter).

Center and Width

Like Min and Max, except you specify a center value and the width of the range around that value.


The (per component) lower end of the value range, when Range is “Min and Max”.


The (per component) upper end of the value range, when Range is “Min and Max”.


The (per component) center of the range, when Range is “Center and Width”.


The width of the range centered around Center, when Range is “Center and Width”.

Out of Range Values

How to color values outside the given range, when Range is “Min and Max” or “Center and Width”.

Roll Cyclically

Color the value as if the ramp repeated endlessly forward and backward.

Black Out

Color out of range values black.

Clamp to Edge Values

Use the first color in the ramp for values less than the range, and the last color in the ramp for values greater than the range.

Treat As Scalar

Convert vector attribute types (with more than one component) to a single value. This enables a menu for choosing how to convert the values.


How to convert multi-component values to a single number, when Treat as scalar is on.


Pick one of the components.

Component Abs.

Pick one of the components, and use its absolute value.

Component Sum

Sum up the component values.

Component Abs. Sum

Sum up the absolute values of the components.


Use the length of the vector.

Length Squared

Use the square of the length of the vector.

Dot Product

Use the dot product of the vector with a given vector. This may be useful for measuring deviance from a certain direction.

Color Ramp Preset

A list of presets for the Color Ramp.

Color Ramp

The colors to map to attribute values.



The color to use for all geometry this visualizer applies to.


Random Seed

The seed for the random number generator. Change this value to get different random colors.

Random from attribute


Name of the attribute to visualize.

Random Seed

The seed for the random number generator. Change this value to get different random colors.

Value Separation

How far apart two values must be to be colored differently. This is useful for floating point values (for example, you might not care about the difference between 0.0001 and 0.0002). It is also useful for “banding” ranges of attribute values.

Polygon vertex count

Color Triangles

Visualize three-sided polygons using this color.

Color quads

Visualize four-sided polygons using this color.

Color n-gons

Visualize polygons with more than four sides using this color.

Texture distortion

Texture attribute

The attribute containing the UV coordinates to visualize. The default is uv.

Houdini 20.0

Getting started

Using Houdini

  • Geometry

    How Houdini represents geometry and how to create and edit it.

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    How to create and simulate muscles, tissue, and skin in Houdini.

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    How to create highly realistic and detailed feathers for your characters.


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    How to break different types of materials.

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    How to simulate grainy materials (such as sand).

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    How to create and simulate deformable objects


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