PathFollow

Inherits: Spatial < Node < Object

Category: Core

Brief Description

Point sampler for a Path.

Member Functions

bool get_cubic_interpolation ( ) const
float get_h_offset ( ) const
float get_offset ( ) const
int get_rotation_mode ( ) const
float get_unit_offset ( ) const
float get_v_offset ( ) const
bool has_loop ( ) const
void set_cubic_interpolation ( bool enable )
void set_h_offset ( float h_offset )
void set_loop ( bool loop )
void set_offset ( float offset )
void set_rotation_mode ( int rotation_mode )
void set_unit_offset ( float unit_offset )
void set_v_offset ( float v_offset )

Numeric Constants

  • ROTATION_NONE = 0 — Forbids the PathFollow to rotate.
  • ROTATION_Y = 1 — Allows the PathFollow to rotate in the Y axis only.
  • ROTATION_XY = 2 — Allows the PathFollow to rotate in both the X, and Y axes.
  • ROTATION_XYZ = 3 — Allows the PathFollow to rotate in any axis.

Description

This node takes its parent Path, and returns the coordinates of a point within it, given a distance from the first vertex.

It is useful for making other nodes follow a path, without coding the movement pattern. For that, the nodes must be descendants of this node. Then, when setting an offset in this node, the descendant nodes will move accordingly.

Member Function Description

  • bool get_cubic_interpolation ( ) const

This method returns whether the position between two cached points (see set_cubic_interpolation) is interpolated linearly, or cubicly.

  • float get_h_offset ( ) const

Returns the X displacement this node has from its parent Path.

  • float get_offset ( ) const

Returns the distance along the path in 3D units.

  • int get_rotation_mode ( ) const

Returns the rotation mode. The constants below list which axes are allowed to rotate for each mode.

  • float get_unit_offset ( ) const

Returns the distance along the path as a number in the range 0.0 (for the first vertex) to 1.0 (for the last).

  • float get_v_offset ( ) const

Returns the Y displacement this node has from its parent Path.

  • bool has_loop ( ) const

Returns whether this node wraps its offsets around, or truncates them to the path ends.

  • void set_cubic_interpolation ( bool enable )

The points along the Curve3D of the Path are precomputed before use, for faster calculations. The point at the requested offset is then calculated interpolating between two adjacent cached points. This may present a problem if the curve makes sharp turns, as the cached points may not follow the curve closely enough.

There are two answers to this problem: Either increase the number of cached points and increase memory consumption, or make a cubic interpolation between two points at the cost of (slightly) slower calculations.

This method controls whether the position between two cached points is interpolated linearly, or cubicly.

  • void set_h_offset ( float h_offset )

Moves this node in the X axis. As this node’s position will be set every time its offset is set, this allows many PathFollow to share the same curve (and thus the same movement pattern), yet not return the same position for a given path offset.

A similar effect may be achieved moving the this node’s descendants.

  • void set_loop ( bool loop )

If set, any offset outside the path’s length (whether set by set_offset or set_unit_offset will wrap around, instead of stopping at the ends. Set it for cyclic paths.

  • void set_offset ( float offset )

Sets the distance from the first vertex, measured in 3D units along the path. This sets this node’s position to a point within the path.

  • void set_rotation_mode ( int rotation_mode )

Allows or forbids rotation on one or more axes, per the constants below.

  • void set_unit_offset ( float unit_offset )

Sets the distance from the first vertex, considering 0.0 as the first vertex and 1.0 as the last. This is just another way of expressing the offset within the path, as the offset supplied is multiplied internally by the path’s length.

  • void set_v_offset ( float v_offset )

Moves this node in the Y axis, for the same reasons of set_h_offset.