Houdini 22.0 Nodes Copernicus nodes

UV Shape Copernicus node

Generates UV coordinates for 2D shapes.

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Since 22.0

This node outputs UV coordinates, a UV filter scale, and a mask for a procedural 2D shape. The node generates the UV values in image coordinates, where the valid sampled range is generally -1 to 1. Use this node when you need to set UVs or fill a shape with a UV map.

Use the uv output with a UV Sample COP to map an image into disks, squares, horseshoes, spirals, annuli, and fish scale patterns.

How to use UV Shape

For example, use the following steps to map an image into a 2D shape.

  1. Create a UV Shape COP and a UV Sample COP in your network.

  2. Wire the UV Shape COP’s uv output into the UV Sample COP’s uv input.

  3. Add the image node that you want mapped into the 2D shape.

    For example, add a Checkerboard COP.

  4. Wire the image node (the Checkerboard COP in this example) into the UV Sample COP’s texture input.

  5. Add a Multiply COP.

  6. Wire the UV Sample COP into the bg input and the UV Shape COP’s mask output into the fg input of the Multiply COP.

  7. Turn on the Multiply COP’s display flag and configure the UV Shape COP to the shape in which you want the image mapped.

    For example, set Shapes to Disk and Mode to Polar.

You now have an image that’s mapped into a 2D shape.

Parameters

Shapes

The shape used to generate the UV coordinates and mask.

Disk

Generate UV coordinates inside a disk.

Square

Generate UV coordinates for a folded square tile.

Horseshoe

Generate UV coordinates for a horseshoe shape (an elongated U).

Spiral

Generate UV coordinates along a spiral band.

Annulus

Generate UV coordinates inside a ring.

Fishscale

Generate UV coordinates for repeating fish scale-shaped tiles.

Disk

Mode

The mapping method to use for the Disk shape.

Linear

Stretch the disk to fit the square UV range. This is inexpensive, but creates more distortion along diagonals.

Polar

Use the disk’s angle for U and its radius for V.

Equal Area

Preserve the relative area while mapping the disk into the square UV range.

Squircle

Use a squircle-based disk-to-square mapping with stable distortion near the axes.

Elliptic Arc

Use an elliptic-arc grid to map the disk into the square UV range.

Conformal

Preserve local angles as much as possible while mapping the disk into the square UV range.

Radius

The radius (in image space) of the Disk shape.

Square

Mode

The mapping method to use for the Square shape.

Linear

Linearly map the folded square region into UV space. This has more uniform distortion inside the shape and near the boundary.

Conformal

Use an angle-preserving mapping for the folded square region. This has less distortion inside the shape but more distortion near the boundary.

You can also set the amount of symmetric folds to use for the square tile.

2-fold

Use a two-way diagonal fold.

4-fold

Use four symmetrical folded regions around the center.

Vertex

The orientation of the image’s central vertex when the Square's Mode is Linear.

Top

Place the mapped vertex at the top.

Left

Place the mapped vertex on the left.

Right

Place the mapped vertex on the right.

Flip Tile Orientation

Flips the orientation of the folded square tile.

Horseshoe

Size

The radius (in image space) of the centerline of the horseshoe’s curved part. Higher values widen and enlarge the centerline.

Separation

The distance (in image space) between the horseshoe’s sides, which controls how open the horseshoe is. Higher values increase the gap between the sides.

Length

The length (in image space) of the horseshoe’s sides.

Thickness

The half width of the horseshoe band around its centerline.

U Adjust

The amount of the U range that’s assigned to the curved part of the horseshoe versus the sides.

Spiral

Spiral Type

The type of Spiral curve to use.

Archimedean

Use an Archimedean spiral, where the radius changes linearly with the angle. The distance between each revolution in these spirals is constant.

Log

Use a logarithmic spiral, where the radius changes exponentially with the angle. The distance between each revolution in these spirals increases.

Loxodrome

Use a loxodrome spiral, which is produced from a transformed logarithmic spiral by a Möbius transformation. This outputs two spirals.

U Mode

The method used to compute the U coordinate along the spiral.

Angle

Base the U coordinate on the Angle parameter of the closest point on the spiral.

Arc Length

Base the U coordinate on the arc length along the spiral. This outputs more uniform U values.

Size

The radial spacing of the Archimedean spiral. Higher values increase the space between each revolution, which widens the spiral shape. Lower values decrease the space between each revolution, which tightens the spiral shape.

Size

The growth rate of the logarithmic (Log) spiral. Higher values increase how much the space between each revolution exponentially grows, which widens the spiral shape. Lower values decrease how much the space between each revolution exponentially grows, which tightens the spiral shape.

Size

The radial spacing and growth rate of the Loxodrome spiral. Higher values increase the space between each revolution and how much the space between each revolution exponentially grows, which widens the spiral shape. Lower values decrease the space between each revolution and how much the space between each revolution exponentially grows, which tightens the spiral shape.

Start Radius

The radius where the spiral starts. Higher values increase the size of the radius where the spiral pattern begins to generate UV coordinates.

Turns

The number of turns in the spiral. Higher values increase the amount of turns in the spiral pattern that generate UV coordinates.

Thickness

The thickness of the UV band around the spiral. Higher values increase how much of the space between each revolution of the spiral pattern generates UV coordinates.

Negative Center

The negative center in image coordinates that the Loxodrome transform uses. This is the location of the radius for the spiral that’s in the negative image space.

Positive Center

The positive center in image coordinates that the Loxodrome transform uses. This is the location of the radius for the spiral that’s in the positive image space.

Annulus

Mode

The mapping method to use for the Annulus shape.

Polar

Use the angle for U and linear radius for V.

Log

Use the angle for U and logarithmic radius for V.

Inner Radius

The inner radius (in image space) of the annulus. Higher values increase the size of the radius where the annulus pattern begins to generate UV coordinates.

Outer Radius

The outer radius (in image space) of the annulus. Higher values increase the size of the radius where the annulus pattern stops generating UV coordinates.

Fishscale

Mode

The method used to generate the Fishscale pattern.

Offset

Generate fish scale cells from offset disk tiles on a grid.

Fill

Fill each fish scale cell by deforming the disk mapping (Disk Mode) into the fish scale shape.

Disk Mode

The disk mapping method to use inside each fish scale cell.

Linear

Stretch the disk to fit the square UV range.

Polar

Use the disk’s angle and radius.

Equal-area

Preserve the relative area while mapping the disk.

Squircle

Use a squircle-based disk-to-square mapping.

Elliptic Arc

Use an elliptic-arc grid mapping.

Conformal

Preserve local angles as much as possible.

Radius

The radius (in image space) of the disk that builds the fish scale cells.

Do Tiled

When Mode is set to Offset, this rounds the Grid Scale so the fish scale pattern cleanly tiles.

Grid Scale

When Mode is set to Offset, this is the overall scale of the fish scale grid. You can turn on the Per-Component Controls button to adjust this further using the Grid Scale parameter.

Grid Scale

When Per-Component Controls is on, this is the per-axis scale of the fish scale grid.

Center Blend

When Mode is set to Fill, this is the width of the blend region near the center singularity.

Center Blend Exponent

When Mode is set to Fill, this is the shape of the blend near the center singularity.

Transform

Offset

The amount in image coordinates to offset the generated UV coordinates (uv).

Angle

The amount in degrees to rotate the generated UV coordinates (uv).

Shear

The amount in image space to shear the generated UV coordinates (uv).

UV

UV Filter Bound

The maximum filter scale to allow in the uvscale output. Higher values increase the amount of anti-aliasing, which reduces jagged edges by smoothing the UV coordinates.

U Border

The method used to handle U values outside of the -1 to 1 range. See Border types for more information.

Clamp

Clamp U to the nearest valid value.

Mirror

Mirror U about the boundary.

Wrap

Repeat U from the opposite side so it wraps around the boundary.

Extend

Leave U unchanged.

U Scale

The amount to scale the generated U coordinates (uv).

V Border

The method used to handle V values outside of the -1 to 1 range. See Border types for more information.

Clamp

Clamp V to the nearest valid value.

Mirror

Mirror V about the boundary.

Wrap

Repeat V from the opposite side so it wraps around the boundary.

Extend

Leave V unchanged.

V Scale

The amount to scale the generated V coordinates (uv).

Inputs

size_ref

A representative layer that determines the size of the output image and controls the metadata.

Outputs

uv

The generated UV coordinates.

uvscale

The filter scale factor for how stretched the UV values are. The UV Filter Bound parameter sets the maximum filter scale allowed in this output.

Wire this output into a UV Sample COP’s filterscale to choose an appropriate filter width.

mask

The mono layer that’s 1 (white) inside of the generated shape and 0 (black) outside of the generated shape.

See also

Copernicus nodes