2009

Contact Object group
Use this control for defining the object on which marks are to be left.
[button] Click this button, and then select an object in the scene to use as
the contact object. The mouse cursor changes to a cross shape when positioned
over a valid object.
After picking a contact object, its name appears on the button.
Align to Surface Animation When on, Shape Mark takes into account surface
changes due to vertex animation of the contact object. If
Shape on page 2916
is set to Rectangle, then the mark changes its orientation and position to
appear be stuck to the surface of the contact object. If Shape is set to Box
Intersection, then the mark changes shape along with that of the contact
object. When off, only transformation of the contact object is taken into
consideration. Default=off.
Turn this on only if there is significant vertex animation at the contact point,
such as with an animated water surface.
WARNING This option requires significant CPU and memory resources.
Orientation group
Align To Depending on the setting for
Shape on page 2916, Shape Mark creates
either a rectangle or a box cutout on the contact geometry. The Orientation
setting specifies how the shape is oriented. In the mark's local coordinate
system, the X axis is Length, the Y axis is Width, and with the box cutout, Z
is height. The Z axis is perpendicular to the surface of the object at the contact
point.
The alignment choices are as follows:
■ Speed The Length direction is parallel to the projection of the particles'
speed vector onto the contact plane.
■ Particle X/Y/Z The Length direction is parallel to the projection of the
particle's local coordinate axis X, Y, or Z, respectively, as the particle moves
toward the contact object.
■ Random Uses a random Length direction in the contact plane.
Divergence Applies a range of random variation, in degrees, to the orientation
of the Length direction. Unavailable when using the Random option.
Particle Flow | 2915