Houdini 20.0 Nodes Geometry nodes

Draw Curve geometry node

Creates a curve based on user input in the viewport.

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Since 13.0

The Draw Curve allows freehand drawing of curves in the viewport. Different projection options allow the curve to be snapped to either a construction plane or a collision geometry.


Drawing with a stylus input device will account for pressure and tilt.

This tool uses the Stroke SOP internally.

Using Draw Curve

To...Do this

Draw a curve anywhere in the scene

  1. Click the Draw Curve tool on the Create tab.

  2. Hold LMB and drag to draw a curve freehand on the construction plane.

Draw a curve on an object

  1. Select an object in the viewport and click the Draw Curve tool on the Create tab..

  2. Hold LMB and drag to draw a curve freehand on the object.



Create Width Attribute

Creates an attribute named width containing the curve’s radius.

When this is disabled, the Radius parameter is used only as the display size of the viewport brush.


Radius of the curve.


When Create Stroke Attributes is enabled, this is stored as integer primitive attribute stroke_tool on each curve. It can be used by tools based on this node to take different actions for each curve.

Create Color Attribute

Create a primitive color attribute.


Color of the curve.

Create Stroke Attributes

Creates attributes containing detailed information about the recorded strokes.

See the Stroke SOP for more information.


Opacity of the curve.


Live Reprojection


Projection is only done at drawing stage.

Send Rays

Reproject by resending rays on underlying changing collision geometry.

Use UVs

Use the uv coordinates from the initial projection on changing collision geometry.

Trim Curves

Delete parts of drawn curves that don’t hit any collision geometry.


XY/YZ/ZX/Screen Plane

Projection of the curve is done on specified orthographic plane.


Projection is done on the collision geometry that is plugged into first input.

Projection Center

Center of the orthographic projection plane.


Cache Strokes

Whether to store all strokes from the Number of Strokes multiparm into an internal cache when a stroke it drawn. This can help with performance when drawing large numbers of curves.

Clear Stroke History

Clears all drawn strokes.


Move Stash to New File

Saves the data parameter into a new file, updates the geometry file to point to the new file, and clears the data parameter. This will externalize the geometry and reduce the size of the .hip file at the cost of having to manage an external file.

The default name and path are controlled by the HOUDINI_STASH_DIR and HOUDINI_STASH_FILENAME environment variables.

Load Stash from File

Explicitly loads the specified geometry file and stores it in the data parameter. This internalizes the stash file. The external file could be deleted after this, as the authoritative copy is now in the data parameter.

Geometry File

File path to store the drawn strokes.

See also

Geometry nodes