/// <summary>
/// Retrieves the angle, expressed in radians, between the two specified vectors.
/// </summary>
/// <param name="vector1">The first vector to evaluate.</param>
/// <param name="vector2">The second vector to evaluate.</param>
/// <returns>The angle, in radians, between vector1 and vector2.</returns>
public static float AngleBetween(VectorF vector1, VectorF vector2)
{
vector1.Normalize();
vector2.Normalize();
double angle = Math.Atan2(vector2.y, vector2.x) - Math.Atan2(vector1.y, vector1.x);
if (angle > Math.PI)
{
angle -= Math.PI * 2.0;
}
else if (angle < -Math.PI)
{
angle += Math.PI * 2.0;
}
return((float)angle);
}
/// <summary>
/// Calculates the cross product of two vectors.
/// </summary>
/// <param name="vector1">The first vector to evaluate.</param>
/// <param name="vector2">The second vector to evaluate.</param>
/// <returns>The cross product of vector1 and vector2. The following formula is used to
/// calculate the cross product: (Vector1.X * Vector2.Y) - (Vector1.Y * Vector2.X)</returns>
public static float CrossProduct(VectorF vector1, VectorF vector2)
{
return((vector1.x * vector2.y) - (vector1.y * vector2.x));
}
/// <summary>
/// Calculates the determinant of two vectors.
/// </summary>
/// <param name="vector1">The first vector to evaluate.</param>
/// <param name="vector2">The second vector to evaluate.</param>
/// <returns>The determinant of vector1 and vector2.</returns>
public static float Determinant(VectorF vector1, VectorF vector2)
{
// In the case of two 2D vectors, the determinant is the cross-product.
return(CrossProduct(vector1, vector2));
}
/// <summary>
/// Divides the specified vector by the specified scalar and returns the result.
/// </summary>
/// <param name="vector">The vector structure to divide.</param>
/// <param name="scalar">The amount by which vector is divided.</param>
/// <returns>The result of dividing vector by scalar.</returns>
public static VectorF Divide(VectorF vector, float scalar)
{
return(vector / scalar);
}
/// <summary>
/// Calculates the dot product of the two specified vectors and returns the result.
/// </summary>
/// <param name="vector1">The first vector to multiply.</param>
/// <param name="vector2">The second vector structure to multiply.</param>
/// <returns>The scalar dot product of vector1 and vector2, which is calculated
/// using the following formula: (vector1.X * vector2.X) + (vector1.Y * vector2.Y)</returns>
public static float Multiply(VectorF vector1, VectorF vector2)
{
return(vector1 * vector2);
}
/// <summary>
/// Multiplies the specified scalar by the specified vector and returns the resulting vector.
/// </summary>
/// <param name="scalar">The scalar to multiply.</param>
/// <param name="vector">The vector to multiply.</param>
/// <returns>The result of multiplying scalar and vector.</returns>
public static VectorF Multiply(float scalar, VectorF vector)
{
return(scalar * vector);
}
/// <summary>
/// Multiplies the specified scalar by the specified vector and returns the resulting vector.
/// </summary>
/// <param name="vector">The vector to multiply.</param>
/// <param name="scalar">The scalar to multiply.</param>
/// <returns>The result of multiplying scalar and vector.</returns>
public static VectorF Multiply(VectorF vector, float scalar)
{
return(vector * scalar);
}
/// <summary>
/// Subtracts the specified vector from another specified vector.
/// </summary>
/// <param name="vector1">The vector from which vector2 is subtracted.</param>
/// <param name="vector2">The vector to subtract from vector1.</param>
/// <returns>The difference between vector1 and vector2.</returns>
public static VectorF Subtract(VectorF vector1, VectorF vector2)
{
return(vector1 - vector2);
}
/// <summary>
/// Translates the specified point by the specified vector and returns the resulting point.
/// </summary>
/// <param name="vector">The amount to translate the specified point.</param>
/// <param name="point">The point to translate.</param>
/// <returns>The result of translating point by vector.</returns>
public static PointF Add(VectorF vector, PointF point)
{
return(vector + point);
}
/// <summary>
/// Adds two vectors and returns the result.
/// </summary>
/// <param name="vector1">The first vector to add.</param>
/// <param name="vector2">The second vector to add.</param>
/// <returns> The sum of vector1 and vector2.</returns>
public static VectorF Add(VectorF vector1, VectorF vector2)
{
return(vector1 + vector2);
}
/// <summary>
/// Compares two vectors for equality.
/// </summary>
/// <param name="value">The vector to compare with this vector.</param>
/// <returns>true if value has the same X and Y values as this vector;
/// otherwise, false.</returns>
public bool Equals(VectorF value)
{
return(value == this);
}
/// <summary>
/// Compares the two specified vectors for equality.
/// </summary>
/// <param name="vector1">The first vector to compare.</param>
/// <param name="vector2">The second vector to compare.</param>
/// <returns>true if the X and Y components of vector1 and vector2 are equal;
/// otherwise, false.</returns>
public static bool Equals(VectorF vector1, VectorF vector2)
{
return(vector1 == vector2);
}
