Describes a Bezier curve in 2D space.
``````    public class Curve2D : Resource
``````

This class describes a Bezier curve in 2D space. It is mainly used to give a shape to a Path2D, but can be manually sampled for other purposes.

It keeps a cache of precalculated points along the curve, to speed further calculations up.

### Constructors

``````    public Curve2D()
``````

### Properties

``````    public Dictionary&lt;object, object&gt; _Data { get; set; }
``````

``````    public float BakeInterval { get; set; }
``````

The distance in pixels between two adjacent cached points. Changing it forces the cache to be recomputed the next time the GetBakedPoints() or GetBakedLength() function is called. The smaller the distance, the more points in the cache and the more memory it will consume, so use with care.

### Methods

``````    public void AddPoint(Vector2 position, Vector2? @in = default(Vector2?), Vector2? @out = default(Vector2?), int atPosition = -1)
``````

Adds a point to a curve, at “position”, with control points “in” and “out”.

If “at_position” is given, the point is inserted before the point number “at_position”, moving that point (and every point after) after the inserted point. If “at_position” is not given, or is an illegal value (at_position <0 or at_position >= GetPointCount()), the point will be appended at the end of the point list.

``````    public void ClearPoints()
``````

Removes all points from the curve.

``````    public float GetBakedLength()
``````

Returns the total length of the curve, based on the cached points. Given enough density (see BakeInterval.set), it should be approximate enough.

``````    public Vector2[] GetBakedPoints()
``````

Returns the cache of points as a PoolVector2Array.

``````    public float GetBakeInterval()
``````

Getter for BakeInterval

``````    public int GetPointCount()
``````

Returns the number of points describing the curve.

``````    public Vector2 GetPointIn(int idx)
``````

Returns the position of the control point leading to the vertex “idx”. If the index is out of bounds, the function sends an error to the console, and returns (0, 0).

``````    public Vector2 GetPointOut(int idx)
``````

Returns the position of the control point leading out of the vertex “idx”. If the index is out of bounds, the function sends an error to the console, and returns (0, 0).

``````    public Vector2 GetPointPosition(int idx)
``````

Returns the position of the vertex “idx”. If the index is out of bounds, the function sends an error to the console, and returns (0, 0).

``````    public Vector2 Interpolate(int idx, float t)
``````

Returns the position between the vertex “idx” and the vertex “idx”+1, where “t” controls if the point is the first vertex (t = 0.0), the last vertex (t = 1.0), or in between. Values of “t” outside the range (0.0 >= t <=1) give strange, but predictable results.

If “idx” is out of bounds it is truncated to the first or last vertex, and “t” is ignored. If the curve has no points, the function sends an error to the console, and returns (0, 0).

``````    public Vector2 InterpolateBaked(float offset, bool cubic = false)
``````

Returns a point within the curve at position “offset”, where “offset” is measured as a pixel distance along the curve.

To do that, it finds the two cached points where the “offset” lies between, then interpolates the values. This interpolation is cubic if “cubic” is set to true, or linear if set to false.

Cubic interpolation tends to follow the curves better, but linear is faster (and often, precise enough).

``````    public Vector2 Interpolatef(float fofs)
``````

Returns the position at the vertex “fofs”. It calls Interpolate(int, float) using the integer part of fofs as “idx”, and its fractional part as “t”.

``````    public void RemovePoint(int idx)
``````

Deletes the point “idx” from the curve. Sends an error to the console if “idx” is out of bounds.

``````    public void SetBakeInterval(float distance)
``````

Setter for BakeInterval

``````    public void SetPointIn(int idx, Vector2 position)
``````

Sets the position of the control point leading to the vertex “idx”. If the index is out of bounds, the function sends an error to the console.

``````    public void SetPointOut(int idx, Vector2 position)
``````

Sets the position of the control point leading out of the vertex “idx”. If the index is out of bounds, the function sends an error to the console.

``````    public void SetPointPosition(int idx, Vector2 position)
``````

Sets the position for the vertex “idx”. If the index is out of bounds, the function sends an error to the console.

``````    public Vector2[] Tessellate(int maxStages = 5, float toleranceDegrees = 4f)
``````

Returns a list of points along the curve, with a curvature controlled point density. That is, the curvier parts will have more points than the straighter parts.

This approximation makes straight segments between each point, then subdivides those segments until the resulting shape is similar enough.

“max_stages” controls how many subdivisions a curve segment may face before it is considered approximate enough. Each subdivision splits the segment in half, so the default 5 stages may mean up to 32 subdivisions per curve segment. Increase with care!

“tolerance_degrees” controls how many degrees the midpoint of a segment may deviate from the real curve, before the segment has to be subdivided.

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