Point sampler for a Path2D.
    public class PathFollow2D : Node2D

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 descendants of this node. Then, when setting an offset in this node, the descendant nodes will move accordingly.

Inheritance Chain

Constructors

    public PathFollow2D()

Properties

    public bool CubicInterp { get; set; }

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.

    public float HOffset { get; set; }

The node’s offset along the curve.

    public float Lookahead { get; set; }

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. Default value: 4.

    public bool Loop { get; set; }

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

    public float Offset { get; set; }

The distance along the path in pixels.

    public bool Rotate { get; set; }

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

    public float UnitOffset { get; set; }

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.

    public float VOffset { get; set; }

The node’s offset perpendicular to the curve.

Methods

    public bool GetCubicInterpolation()

Getter for CubicInterp

    public float GetHOffset()

Getter for HOffset

    public float GetLookahead()

Getter for Lookahead

    public float GetOffset()

Getter for Offset

    public float GetUnitOffset()

Getter for UnitOffset

    public float GetVOffset()

Getter for VOffset

    public bool HasLoop()

Getter for Loop

    public bool IsRotating()

Getter for Rotate

    public void SetCubicInterpolation(bool enable)

Setter for CubicInterp

    public void SetHOffset(float hOffset)

Setter for HOffset

    public void SetLookahead(float lookahead)

Setter for Lookahead

    public void SetLoop(bool loop)

Setter for Loop

    public void SetOffset(float offset)

Setter for Offset

    public void SetRotate(bool enable)

Setter for Rotate

    public void SetUnitOffset(float unitOffset)

Setter for UnitOffset

    public void SetVOffset(float vOffset)

Setter for VOffset

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