Since | 17.0 |

This node generates point geometry from a height field.

## Parameters ¶

Tag Name

The name of the tag attribute added to the generated points from this node. By default it is set to `$OS`

which is the name of the node.

Scatter Method

How to scatter the points.

By Coverage using Mask Layer

Given a certain **Coverage** value and **Variability** values, this method will scatter points so that they would cover the set amount of **Coverage** on the painted mask on the heightfield.

By Density using Mask Layer

Given a certain **Density** value, this method will scatter points so that they would have **Density** as their number of points per meter square on the painted mask on the heightfield.

Total Point Count using Mask Layer

Given a certain **Total Point Count** value, this method will scatter points so that they would have exactly the number set as their number of points on the painted mask on the heightfield.

Per Point Count using Source Points

Given a certain range or exact value, this method will scatter points around the points with tags matching **Source Point Tag**.

## Scattering ¶

Mask Layer

The name of a mask layer specifying which areas of the height field will get scattered points.

Coverage

The ratio of area of the painted mask on the input height field that should be covered with the points about to be scattered given their size from the **Variability** section.

Density

The number of points per square meter to generate on the painted mask on the input height field.

Total Point Count

The exact number of points to be scattered on the painted mask on the input height field.

Source Point Tag

The name of the tag attribute from the source points that the new points would be scattered around. If points are fed into the second input, the node will look in the set of points in the second input for tags matching this string instead of the first input.

Per Point Count Method

How to scatter the newly generated points around the source points.

Poisson Distribution

Scatter points according to a poisson distribution given the range.

Exact Number

Scatter points by exactly placing down *Exact Number* many points.

Range

The range that the poisson distribution spans on.

Exact Number

The exact number of points to be scattered around the points with matching tags as **Source Point Tag**.

Positioning Method

How to position points around the source points. Points are uniformly scattered in the circular rings around the source points.

Offset

Treat the numbers as the min and max radius away from the inner radius of the source points.

Origin

Treat the numbers as the min and max radius away from the origin of the source points.

Ratio

Treat the numbers as the min and max ratios on the inner radius of the source points away from their origin.

Source Origin Radius

Source Inner Radius Offset

The inner and the outer radius of a circular ring indicated as offset to the inner radius of the source points.

Source Inner Radius Ratio

The inner and the outer ratio of a circular ring applied on the inner radius of the source points.

Outer Radius

Sets the radius away from the origin of the points that is considered to be the physical area occupied by the points. This value is scaled according to parameters in **Variability** and stored in the **footprint** attribute.

Falloff

When not equal to zero, it indicates the inner radius away from the origin of the points.

## Variability ¶

Method

How to scale the generated points.

Uniform Distribution

Scale points according to a uniform distribution given the range.

Normal Distribution

Scale points according to a normal distribution given the range and the spread (the standard deviation of the distribution).

Exact Scale

Scale points by a fixed amount.

Range

The range that the uniform distribution spans on.

Range

Sets the min and max of the values that are accepted from a normal distribution with a mean equal to the average of the min and max values, and a standard deviation of **Spread**.

Spread

Set the standard deviation of the normal distribution. Increasing this number with a fixed range results in lower number of points scattered.

Exact Scale

Set the exact amount that all points will be scaled by.

## Relaxation ¶

Relax Points

Pushes points away from each other as a secondary step, to prevent clumping.

Self Overlap

Whether to apply relaxation between the newly generated points or not.

Avoid Point Tag

The name of the tag attribute of the points that relaxation will take place on.

Mask Cut Off

The minimum value of the mask which is considered to actually be painted area. Outside of this area, points are removed.

Iterations

When **Relax points** is on, the number of iterations of relaxation to do. More iterations will more evenly distribute the points, but can be slower, and after a certain number of iterations that evenly distribute the points, more iterations is wasted effort.

Removing Rate

The rate at which the points would be removed while relaxing. If set to a lower value, more iterations are needed to reach a stable output, but there is more control.

Stepping Ratio

The ratio of the calculated intersecting distance between two points that is moved per iteration.

Allow Out of Bounds Points

When turned on, points outside the bounds of the heightfield will not be removed.

Point Removal Method

Keep Incoming Scatter Points

When turned on, the output will include the incoming scatter points together with the newly scattered points.

Keep Incoming Terrain

When turned on, the output will include the input height field with all its layers.

Randomize Orients

When turned on, randomize the point orientations around their normal vector.

Match Normals with Terrain

When turned on, match the normal vectors of every point to the normal of the terrain at that location.

Match Direction with Slope

When turned on, rotate around the normal vector so the Z-direction is facing along the slope of the terrain.

Randomize Up

Specify the number of degrees to jitter the computed normal direction of the instance.

Randomize Yaw

Specify the number of degrees to rotate around the normal. 180 will provide completely random directions.

Instance on New Points

When turned on, use the primitives on the third input to pack them and instance them on every point.

Define Pieces

From Attribute

Use the **Piece Attribute** to figure out the pieces connected to the input. If the attribute is missing, it is treated as a single piece.

From Connectivity

Internally use a connectivity sop to figure out the pieces of the input primitives.

Single Piece

Treat the instance geometry as one single piece.

Piece Attribute

Sets the string that node uses to find the primitive piece attribute attached to each piece.

Quantization

Sets the value that the position of newly generated points are quantized to.

Global Seed

Seed for the random number generator. Using the same seed always produces the same scattering. For example, you can change the value to get a different scattering, or set it `$F`

to get a different scattering on every frame.

Max Points

An optional hard limit on the number of points to generate, to prevent accidents where you mistype a value and Houdini tries to generate a ridiculous number of points that locks up the computer.

Note

Do not rely on this parameter to set a specific number of points. The actual generated points will be less than this, but could be much less depending on seed values and the density. Use total point count scattering or adjust the density.

See also |