The Position Raycast operator allows you to cast rays towards the surface of an object, and place particles where the rays hit.
The origin object was originally reserved for tyIcons only, but now any mesh object is permitted.
Origin object z-axis: rays will be cast along the z-axis of the origin object’s transform.
Nearest origin object normal: rays will be cast along the nearest surface normal to the particle’s input position.
Particle Position: rays will be cast from the particle’s current position.
Project from origin object: rays will be cast from the particle’s current position, projected onto the plane perpendicular to the z-axis of the origin object’s transform.
Random on origin object: rays will be cast from a random location on the origin object.
Value: the amount to interpolate particle positionx from their previous value to the new value.
Keep original: particle orientations will not be changed.
Surface: particles will be aligned to the surface their ray hit.
The Position Raycast operator offers no extra controls over surface alignment. A Rotation operator should be used instead if more control over surface alignment is required.