com.badlogic.gdx.math

Class Bezier<T extends Vector<T>>

java.lang.Object

com.badlogic.gdx.math.Bezier<T>

All Implemented Interfaces:

Path<T>

public class Bezier<T extends Vector<T>>
extends Object
implements Path<T>

Implementation of the Bezier curve.

Author:

Xoppa

Field Summary

Fields

Modifier and Type	Field and Description
Array<T>	points

Constructor Summary

Constructors

Constructor and Description
Bezier()
Bezier(Array<T> points, int offset, int length)
Bezier(T... points)
Bezier(T[] points, int offset, int length)

Method Summary

Methods

Modifier and Type	Method and Description
float	approximate(T v)
float	approxLength(int samples)
static <T extends Vector<T>> T	cubic_derivative(T out, float t, T p0, T p1, T p2, T p3, T tmp) Cubic Bezier curve derivative
static <T extends Vector<T>> T	cubic(T out, float t, T p0, T p1, T p2, T p3, T tmp) Cubic Bezier curve
T	derivativeAt(T out, float t)
static <T extends Vector<T>> T	linear_derivative(T out, float t, T p0, T p1, T tmp) Simple linear interpolation derivative
static <T extends Vector<T>> T	linear(T out, float t, T p0, T p1, T tmp) Simple linear interpolation
float	locate(T v)
static <T extends Vector<T>> T	quadratic_derivative(T out, float t, T p0, T p1, T p2, T tmp) Quadratic Bezier curve derivative
static <T extends Vector<T>> T	quadratic(T out, float t, T p0, T p1, T p2, T tmp) Quadratic Bezier curve
Bezier	set(Array<T> points, int offset, int length)
Bezier	set(T... points)
Bezier	set(T[] points, int offset, int length)
T	valueAt(T out, float t)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

points

public Array<T extends Vector<T>> points

Constructor Detail

Bezier

public Bezier()

Bezier

public Bezier(T... points)

Bezier

public Bezier(T[] points,
      int offset,
      int length)

Bezier

public Bezier(Array<T> points,
      int offset,
      int length)

Method Detail

linear

public static <T extends Vector<T>> T linear(T out,
                             float t,
                             T p0,
                             T p1,
                             T tmp)

Simple linear interpolation

Parameters:

out - The Vector to set to the result.

t - The location (ranging 0..1) on the line.

p0 - The start point.

p1 - The end point.

tmp - A temporary vector to be used by the calculation.

Returns:

The value specified by out for chaining

linear_derivative

public static <T extends Vector<T>> T linear_derivative(T out,
                                        float t,
                                        T p0,
                                        T p1,
                                        T tmp)

Simple linear interpolation derivative

Parameters:

out - The Vector to set to the result.

t - The location (ranging 0..1) on the line.

p0 - The start point.

p1 - The end point.

tmp - A temporary vector to be used by the calculation.

Returns:

The value specified by out for chaining

quadratic

public static <T extends Vector<T>> T quadratic(T out,
                                float t,
                                T p0,
                                T p1,
                                T p2,
                                T tmp)

Quadratic Bezier curve

Parameters:

out - The Vector to set to the result.

t - The location (ranging 0..1) on the curve.

p0 - The first bezier point.

p1 - The second bezier point.

p2 - The third bezier point.

tmp - A temporary vector to be used by the calculation.

Returns:

The value specified by out for chaining

quadratic_derivative

public static <T extends Vector<T>> T quadratic_derivative(T out,
                                           float t,
                                           T p0,
                                           T p1,
                                           T p2,
                                           T tmp)

Quadratic Bezier curve derivative

Parameters:

out - The Vector to set to the result.

t - The location (ranging 0..1) on the curve.

p0 - The first bezier point.

p1 - The second bezier point.

p2 - The third bezier point.

tmp - A temporary vector to be used by the calculation.

Returns:

The value specified by out for chaining

cubic

public static <T extends Vector<T>> T cubic(T out,
                            float t,
                            T p0,
                            T p1,
                            T p2,
                            T p3,
                            T tmp)

Cubic Bezier curve

Parameters:

out - The Vector to set to the result.

t - The location (ranging 0..1) on the curve.

p0 - The first bezier point.

p1 - The second bezier point.

p2 - The third bezier point.

p3 - The fourth bezier point.

tmp - A temporary vector to be used by the calculation.

Returns:

The value specified by out for chaining

cubic_derivative

public static <T extends Vector<T>> T cubic_derivative(T out,
                                       float t,
                                       T p0,
                                       T p1,
                                       T p2,
                                       T p3,
                                       T tmp)

Cubic Bezier curve derivative

Parameters:

out - The Vector to set to the result.

t - The location (ranging 0..1) on the curve.

p0 - The first bezier point.

p1 - The second bezier point.

p2 - The third bezier point.

p3 - The fourth bezier point.

tmp - A temporary vector to be used by the calculation.

Returns:

The value specified by out for chaining

set

public Bezier set(T... points)

set

public Bezier set(T[] points,
         int offset,
         int length)

set

public Bezier set(Array<T> points,
         int offset,
         int length)

valueAt

public T valueAt(T out,
        float t)

Specified by:

valueAt in interface Path<T extends Vector<T>>

Returns:

The value of the path at t where 0<=t<=1

derivativeAt

public T derivativeAt(T out,
             float t)

Specified by:

derivativeAt in interface Path<T extends Vector<T>>

approximate

public float approximate(T v)

Specified by:

approximate in interface Path<T extends Vector<T>>

Returns:

The approximated value (between 0 and 1) on the path which is closest to the specified value. Note that the implementation of this method might be optimized for speed against precision, see Path.locate(Object) for a more precise (but more intensive) method.

locate

public float locate(T v)

Specified by:

locate in interface Path<T extends Vector<T>>

Returns:

The precise location (between 0 and 1) on the path which is closest to the specified value. Note that the implementation of this method might be CPU intensive, see Path.approximate(Object) for a faster (but less precise) method.

approxLength

public float approxLength(int samples)

Specified by:

approxLength in interface Path<T extends Vector<T>>

Parameters:

samples - The amount of divisions used to approximate length. Higher values will produce more precise results, but will be more CPU intensive.

Returns:

An approximated length of the spline through sampling the curve and accumulating the euclidean distances between the sample points.