Curve3D

Inherits: Resource < RefCounted < Object

Describes a Bézier curve in 3D space.

Description

This class describes a Bézier curve in 3D space. It is mainly used to give a shape to a Path3D, but can be manually sampled for other purposes.

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

Properties

Methods

Property Descriptions

float bake_interval = 0.2 🔗

• void set_bake_interval(value: float)

• float get_bake_interval()

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

int point_count = 0 🔗

• void set_point_count(value: int)

• int get_point_count()

The number of points describing the curve.

bool up_vector_enabled = true 🔗

• void set_up_vector_enabled(value: bool)

• bool is_up_vector_enabled()

If true, the curve will bake up vectors used for orientation. This is used when PathFollow3D.rotation_mode is set to PathFollow3D.ROTATION_ORIENTED. Changing it forces the cache to be recomputed.

Method Descriptions

void add_point(position: Vector3, in: Vector3 = Vector3(0, 0, 0), out: Vector3 = Vector3(0, 0, 0), index: int = -1) 🔗

Adds a point with the specified position relative to the curve’s own position, with control points in and out. Appends the new point at the end of the point list.

If index is given, the new point is inserted before the existing point identified by index index. Every existing point starting from index is shifted further down the list of points. The index must be greater than or equal to 0 and must not exceed the number of existing points in the line. See point_count.

void clear_points() 🔗

Removes all points from the curve.

float get_baked_length() const 🔗

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

PackedVector3Array get_baked_points() const 🔗

Returns the cache of points as a PackedVector3Array.

PackedFloat32Array get_baked_tilts() const 🔗

Returns the cache of tilts as a PackedFloat32Array.

PackedVector3Array get_baked_up_vectors() const 🔗

Returns the cache of up vectors as a PackedVector3Array.

If up_vector_enabled is false, the cache will be empty.

float get_closest_offset(to_point: Vector3) const 🔗

Returns the closest offset to to_point. This offset is meant to be used in sample_baked or sample_baked_up_vector.

to_point must be in this curve’s local space.

Vector3 get_closest_point(to_point: Vector3) const 🔗

Returns the closest point on baked segments (in curve’s local space) to to_point.

to_point must be in this curve’s local space.

Vector3 get_point_in(idx: int) const 🔗

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

Vector3 get_point_out(idx: int) const 🔗

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

Vector3 get_point_position(idx: int) const 🔗

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, 0).

float get_point_tilt(idx: int) const 🔗

Returns the tilt angle in radians for the point idx. If the index is out of bounds, the function sends an error to the console, and returns 0.

void remove_point(idx: int) 🔗

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

Vector3 sample(idx: int, t: float) const 🔗

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, 0).

Vector3 sample_baked(offset: float = 0.0, cubic: bool = false) const 🔗

Returns a point within the curve at position offset, where offset is measured as a distance in 3D units 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).

Vector3 sample_baked_up_vector(offset: float, apply_tilt: bool = false) const 🔗

Returns an up vector within the curve at position offset, where offset is measured as a distance in 3D units along the curve. To do that, it finds the two cached up vectors where the offset lies between, then interpolates the values. If apply_tilt is true, an interpolated tilt is applied to the interpolated up vector.

If the curve has no up vectors, the function sends an error to the console, and returns (0, 1, 0).

Transform3D sample_baked_with_rotation(offset: float = 0.0, cubic: bool = false, apply_tilt: bool = false) const 🔗

Returns a Transform3D with origin as point position, basis.x as sideway vector, basis.y as up vector, basis.z as forward vector. When the curve length is 0, there is no reasonable way to calculate the rotation, all vectors aligned with global space axes. See also sample_baked.

Vector3 samplef(fofs: float) const 🔗

Returns the position at the vertex fofs. It calls sample using the integer part of fofs as idx, and its fractional part as t.

void set_point_in(idx: int, position: Vector3) 🔗

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. The position is relative to the vertex.

void set_point_out(idx: int, position: Vector3) 🔗

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. The position is relative to the vertex.

void set_point_position(idx: int, position: Vector3) 🔗

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

void set_point_tilt(idx: int, tilt: float) 🔗

Sets the tilt angle in radians for the point idx. If the index is out of bounds, the function sends an error to the console.

The tilt controls the rotation along the look-at axis an object traveling the path would have. In the case of a curve controlling a PathFollow3D, this tilt is an offset over the natural tilt the PathFollow3D calculates.

PackedVector3Array tessellate(max_stages: int = 5, tolerance_degrees: float = 4) const 🔗

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.

PackedVector3Array tessellate_even_length(max_stages: int = 5, tolerance_length: float = 0.2) const 🔗

Returns a list of points along the curve, with almost uniform density. 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_length controls the maximal distance between two neighboring points, before the segment has to be subdivided.

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