Basics Put parameter controls in the viewer

HUD (Heads-up Display) sliders let you put controls for important parameters directly in the viewer pane, floating above the scene.

These sliders give you constant access to these parameters without having to select the node in the network. HUD sliders are persistent. They remain visible regardless of what node is selected or what tool you are using.

Tip

HUD sliders are disabled when you use some Houdini tools such as View. If your HUD sliders appear dimmed, switch to another tool to re-enable the HUD sliders.

See also promoting parameters and digital assets.

To...	Do this
Create a HUD slider	Drag a parameter from the parameter editor and drop it on the viewer pane. Click HUD Slider. Optionally drag to position and resize the sliders (see below). Press on the slider and choose Locked.
Remove a HUD slider	Click on the slider and turn off the Persistent checkbox.
Edit a slider’s range	By default most sliders use a parameter range of 0 to 1, although you can drag the slider beyond these values. Press on the slider and choose Handle Parameters. Enter the values for the low end and high end of the slider. If you want to prevent the value from being dragged out of the range, turn on Lock Low and/or Lock High.
Switch between positioning/resizing sliders and using them	To switch a slider to usable mode (so you can change the slider value) Press on the slider and check Locked. To switch a slider to be movable/resizable, press on the slider and uncheck Locked.
Position and resize a slider	Unlock the slider so it’s movable/resizable. To move the slider, drag the slider bar. To resize the slider, drag the right edge of the slider box.
Dock sliders together to move/resize them as a group	Drag a slider next to another slider or group of similar size. The slider will automatically dock itself with the other slider(s).
Break up docked sliders	Press on the slider and uncheck Docked.
Show/hide HUD sliders	Right click the Handles tool in the toolbox (on the left side of the viewer) to see a list of available handles. You can turn HUD sliders on or off in this menu. You can use the handle list pane to show/hide sliders, and also to group sliders and other persistent handles together to show/hide them all at once.