PathFollow2D

Inherits: Node2D < CanvasItem < Node < Object

Point sampler for a Path2D.

Description

This node takes its parent Path2D, 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 children of this node. The descendant nodes will then move accordingly when setting an offset in this node.

Properties

bool	cubic_interp	true
float	h_offset	0.0
float	lookahead	4.0
bool	loop	true
float	offset	0.0
bool	rotate	true
float	unit_offset	0.0
float	v_offset	0.0

Property Descriptions

bool cubic_interp

Default	true
Setter	set_cubic_interpolation(value)
Getter	get_cubic_interpolation()

If true, the position between two cached points is interpolated cubically, and linearly otherwise.

The points along the Curve2D of the Path2D 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.

float h_offset

Default	0.0
Setter	set_h_offset(value)
Getter	get_h_offset()

The node's offset along the curve.

float lookahead

Default	4.0
Setter	set_lookahead(value)
Getter	get_lookahead()

How far to look ahead of the curve to calculate the tangent if the node is rotating. E.g. shorter lookaheads will lead to faster rotations.

bool loop

Default	true
Setter	set_loop(value)
Getter	has_loop()

If true, any offset outside the path's length will wrap around, instead of stopping at the ends. Use it for cyclic paths.

float offset

Default	0.0
Setter	set_offset(value)
Getter	get_offset()

The distance along the path in pixels.

bool rotate

Default	true
Setter	set_rotate(value)
Getter	is_rotating()

If true, this node rotates to follow the path, making its descendants rotate.

float unit_offset

Default	0.0
Setter	set_unit_offset(value)
Getter	get_unit_offset()

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

float v_offset

Default	0.0
Setter	set_v_offset(value)
Getter	get_v_offset()

The node's offset perpendicular to the curve.