Houdini 19.5 What’s new What was new in Houdini 17

What’s new in Houdini 17 User interface, Scripting, General

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  • Secure selection” is now on by default. This means when you're in a state with handles that allows selection, you must use the S key to select.

    S is a volatile hotkey. You can tap S to temporarily enter the select state, perform the selection, and then tap S again to return to the previous state. Or, you can hold S, perform the selection, and then release S to return to the previous state.

    For example, the Move tool gives you translate handles for the selected object(s). With secure selection off, you can click freely to select other objects to translate. With secure selection on, you can only interact with the handles. To change the selection, you must use the S key.

    This is intended to prevent accidental selection changes due to mis-clicks when trying to use handles. You can turn secure selection off if you prefer (see below).

  • The Secure Selection setting for the session is now controlled by a button below the Select tool in the toolbar to the left of the viewer. (Previously it was in a pop-up menu attached to the Select tool.)

  • To turn off Secure Selection by default, choose Edit ▸ Preferences ▸ Objects and Geometry, and turn off Secure Selection On by Default.

  • The scene viewer now shows an icon indicating whether secure selection is on or off next to the viewport menus.

Network editor

  • MMB info window now shows which attributes are added, deleted, or (optionally) changed by the node. You can click an attribute name in the info window to create a visualizer for the attribute.

Parameter editor

  • More options in the parameter search and filter interface, including hidden and invisible paramters.

  • Color editor now supports specifying colors using hex (for example FF9900).

Python scripting (HOM)

  • New framework for scripting custom viewer tool states. You can create a state that takes over the viewer when the Handles tool is editing your asset, or even create a “nodeless” state, for example to inspect geometry.

    Currently you can only create SOP-level states.

    This exciting new feature was built as much as possible on existing code and functionality in Houdini. As such, the overall workflow can be quite low-level. We look forward to users making their own custom states and giving us feedback on how to improve the process.

  • New OnInstall and OnUninstall asset event callbacks. These scripts run when the library file the asset is inside is installed or removed. Also, OnUninstall runs before an asset’s definition is changed, and OnInstall runs after the definition is changed.

  • More support in HOM for crowds.

  • hou.hmath.intersectPlane() finds the intersection between a ray and an arbitrary plane.

  • New methods on hou.Node:

  • You can now specify the icon and label in the operation toolbar when you script asking for a selection with the hou.SceneViewer selection methods.

  • You can now pass arguments to the callback script in hou.Parm.pressButton().

Command line

  • New -desktop startup argument lets you specify which pane layout Houdini should start in. This is a one-time override that does not change the saved desktop preference.

    > houdini -desktop Animate
  • New startup switches -core, and -force-fx-license let you specify what type of license Houdini should use.

What was new in Houdini 17