Sound object

When the object is re-parented, maintain its current world position by changing the object’s transform parameters.

This menu contains options for manipulating the pre-transform values. The pre-transform is an internal transform that is applied prior to the regular transform parameters. This allows you to change the frame of reference for the translate, rotate, scale parameter values below without changing the overall transform.

The left menu chooses the order in which transforms are applied (for example, scale, then rotate, then translate). This can change the position and orientation of the object, in the same way that going a block and turning east takes you to a different place than turning east and then going a block.

The right menu chooses the order in which to rotate around the X, Y, and Z axes. Certain orders can make character joint transforms easier to use, depending on the character.

Translation along XYZ axes.

Degrees rotation about XYZ axes.

Non-uniform scaling about XYZ axes.

Local origin of the object. See also setting the pivot point .

Scale the object uniformly along all three axes.

Object to point to. Constrains an object so its -Z axis always points at another object’s origin.

When specifying a look at, it is possible to specify an up vector for the look at. This controls the roll of this object when looking at the look at object.

A reference to the curve node or object you want this object to follow.

The orientation of the object around the path.

The position of the object along the path. 0.0 means at the beginning of the path, and 1.0 means the end. The integer portion of the position is used as the primitive number inside the geometry while the fractional part indicates the u value on the primitive.

If the primitive number does not exist, then it is wrapped back to the beginning. So for numbers greater than 1.0 in a path object that only have a single primitive, it wraps around to the beginning again. You can easily animate something moving around a circular track simply by continuously increasing the position value.

Keyframe this value to animate the object moving along the path.

The Parameterization option controls how position values between 0 and 1 correspond to knots on the path curve.

Controls how the Position parameter is translated into a point on the path curve. Use Arc-length (the default) to interpolate the position values evenly along the physical length of the curve.

Use Uniform to distribute the position values between the knots of the curve. This lets you slow down the object at certain points by bunching up knots in the path curve. However, it is much more convenient to simply edit the animation curve to control the speed of the object along the path.

Orient the object according to the path’s curvature.

The direction vector of the object’s Y axis to orient with.

Controls automatic banking of the object as it turns corners. Set this to 0 to turn automatic banking off.

Turns the sound source on (if greater than zero) or off.

The volume of the sound source.

If off, the sound source is non-directional and emits sound equally in all directions. Otherwise, the sound source is directional and pointed down the negative Z axis. The emission cone and outer cone parameters determine the field of emission. Any sound emitted from within the emission cone have a gain defined by the volume (above). Any sound emitted outside the outer cone have a gain defined by the outer volume parameter (below). Any sound emitted between the recording cone and the outer cone have a gain that is interpolated between the two volumes.

Defines the angle of the emission cone, measured from the Z axis to the edge of the cone. Setting this to 180 degrees will make a non-directional sound source.

Defines the dropoff region from the emission cone to the outer cone. If the emission cone is set to 60 degrees and the outer cone is set to 20 degrees, any sounds emitted from more than 80 degrees off the Z axis will fall outside the outer cone.

Sets the interpolation type for the dropoff from the emission cone volume to the outer volume.

Increases or decreases the rate of dropoff.

The gain that is applied to any sounds coming from outside the outer cone.

Specifies the CHOP that contains the audio that this Sound object is emitted. Only one audio track can be emitted; if there is more than one audio track in the CHOP, the first one is used.

Use the specified wireframe color

The display color of the object

Object is capable of being picked in viewport.

Script to run when the object is picked in the viewport. See select scripts .

Caches object transforms once Houdini calculates them. This is especially useful for objects whose world space position is expensive to calculate (such as Sticky objects), and objects at the end of long parenting chains (such as Bones). This option is turned on by default for Sticky and Bone objects.

See OBJ cache preferences for how to control the size of the object transform cache.