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.
Absolute X/Y/Z: rays will be cast along the specified normal vector.
Custom Vector: rays will be cast along the custom vector of the specified channel.
Direction from origin object pivot: rays will be cast from the raycast origin object pivot to the particle’s raycast origin position.
Nearest origin object normal: rays will be cast along the nearest surface normal to the particle’s input position.
Origin object z-axis: rays will be cast along the z-axis of the origin object’s transform.
Particle X/Y/Z: rays will be cast along the local X/Y/Z axis of the particle’s transform.
Reverse direction: when enabled, each ray’s direction will be reversed.
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.
Offset: offsets the ray’s starting point along the negative raycast direction by the specified amount.
Use the offset feature if you want a particle’s ray to collide with a surface that its ray’s starting point is inside of.
Infinite: rays will hit objects at any distane from their starting point.
Minimum: rays will only hit objects beyond the specified minimum distance from their starting point.
Maximum: rays will only hit objects up to the specified maximum distance from their starting point.
Distance: the specified distance for non-infinite rays.
No offset: the resulting position will be the exact raycast hit location on the target mesh.
Offset along reverse raycast direction: the resulting position will be the raycast hit location offset along the negative raycast direction.
Offset along surface normal: the resulting position will be the raycast hit location offset along the nearest surface normal of the target mesh.
Offset: the amount to offset resulting positions, if applicable.
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.