Vector functions¶
Common Vector Operations¶
Common Vector manipulation functions.
- pyrr.vector.dot(v1, v2)[source]¶
Calculates the dot product of two vectors.
- Parameters
v1 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
v2 (numpy.array) – an Nd array with the final dimension being size 3 (a vector)
- Return type
If a 1d array was passed, it will be a scalar. Otherwise the result will be an array of scalars with shape vec.ndim with the last dimension being size 1.
- pyrr.vector.interpolate(v1, v2, delta)[source]¶
Interpolates between 2 arrays of vectors (shape = N,3) by the specified delta (0.0 <= delta <= 1.0).
- Parameters
v1 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
v2 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
delta (float) – The interpolation percentage to apply, where 0.0 <= delta <= 1.0. When delta is 0.0, the result will be v1. When delta is 1.0, the result will be v2. Values inbetween will be an interpolation.
- Return type
A numpy.array with shape v1.shape.
- pyrr.vector.length(vec)[source]¶
Returns the length of an Nd list of vectors or a single vector.
- Parameters
vec (numpy.array) –
an Nd array with the final dimension being size 3 (a vector).
Single vector:
numpy.array([ x, y, z ])
Nd array:
numpy.array([ [x1, y1, z1], [x2, y2, z2] ]).
- Return type
If a 1d array was passed, it will be a scalar. Otherwise the result will be an array of scalars with shape vec.ndim with the last dimension being size 1.
- pyrr.vector.normalise(vec)[source]¶
normalizes an Nd list of vectors or a single vector to unit length.
The vector is not changed in place.
For zero-length vectors, the result will be np.nan.
- Parameters
vec (numpy.array) –
an Nd array with the final dimension being vectors
numpy.array([ x, y, z ])
Or an NxM array:
numpy.array([ [x1, y1, z1], [x2, y2, z2] ]).
- Return type
A numpy.array the normalized value
- pyrr.vector.normalize(vec)[source]¶
normalizes an Nd list of vectors or a single vector to unit length.
The vector is not changed in place.
For zero-length vectors, the result will be np.nan.
- Parameters
vec (numpy.array) –
an Nd array with the final dimension being vectors
numpy.array([ x, y, z ])
Or an NxM array:
numpy.array([ [x1, y1, z1], [x2, y2, z2] ]).
- Return type
A numpy.array the normalized value
- pyrr.vector.set_length(vec, len)[source]¶
Resizes an Nd list of vectors or a single vector to ‘length’.
The vector is not changed in place.
- Parameters
vec (numpy.array) –
an Nd array with the final dimension being size 3 (a vector).
- Single vector::
numpy.array([ x, y, z ])
- Nd array::
- numpy.array([
[x1, y1, z1], [x2, y2, z2]
]).
- Return type
A numpy.array of shape vec.shape.
- pyrr.vector.squared_length(vec)[source]¶
Calculates the squared length of a vector.
Useful when trying to avoid the performance penalty of a square root operation.
- Parameters
vec (numpy.array) – An Nd numpy.array.
- Return type
If one vector is supplied, the result with be a scalar. Otherwise the result will be an array of scalars with shape vec.ndim with the last dimension being size 1.
Vector3¶
Provides functions for creating and manipulating 3D vectors.
- pyrr.vector3.create_from_vector4(vector, dtype=None)[source]¶
Returns a vector3 and the W component as a tuple.
- pyrr.vector3.cross(v1, v2)[source]¶
Calculates the cross-product of two vectors.
- Parameters
v1 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
v2 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
- Return type
A np.array with shape v1.shape.
- pyrr.vector3.generate_normals(v1, v2, v3, normalize_result=True)[source]¶
Generates a normal vector for 3 vertices.
The result is a normalized vector.
It is assumed the ordering is counter-clockwise starting at v1, v2 then v3:
v1 v3 \ / v2
The vertices are Nd arrays and may be 1d or Nd. As long as the final axis is of size 3.
- For 1d arrays::
>>> v1 = numpy.array( [ 1.0, 0.0, 0.0 ] ) >>> v2 = numpy.array( [ 0.0, 0.0, 0.0 ] ) >>> v3 = numpy.array( [ 0.0, 1.0, 0.0 ] ) >>> vector.generate_normals( v1, v2, v3 ) array([ 0., 0., -1.])
- For Nd arrays::
>>> v1 = numpy.array( [ [ 1.0, 0.0, 0.0 ], [ 1.0, 0.0, 0.0 ] ] ) >>> v2 = numpy.array( [ [ 0.0, 0.0, 0.0 ], [ 0.0, 0.0, 0.0 ] ] ) >>> v3 = numpy.array( [ [ 0.0, 1.0, 0.0 ], [ 0.0, 1.0, 0.0 ] ] ) >>> vector.generate_normals( v1, v2, v3 ) array([[ 0., 0., -1.], [ 0., 0., -1.]])
- Parameters
v1 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
v2 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
v3 (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
normalize_result (boolean) – Specifies if the result should be normalized before being returned.
- pyrr.vector3.generate_vertex_normals(vertices, index, normalize_result=True)[source]¶
Generates a normal vector for each vertex.
The result is a normalized vector.
The index array should list the faces by indexing into the vertices array. It is assumed the ordering in index is counter-clockwise.
The vertices and index arrays are Nd arrays and must be 2d, where the final axis is of size 3.
- An example::
>>> vertices = numpy.array( [ [ 1.0, 0.0, 0.0 ], [ 0.0, 0.0, 0.0 ], [ 0.0, 1.0, 0.0 ] ] ) >>> index = numpy.array( [ [ 0, 2, 1 ] ] ) >>> vector.generate_vertex_normals( vertices, index ) array([[ 0., 0., 1.], [ 0., 0., 1.], [ 0., 0., 1.]])
- Parameters
vertices (numpy.array) – an 2d array with the final dimension being size 3. (a vector)
index (numpy.array) – an Nd array with the final dimension being size 3. (a vector)
normalize_result (boolean) – Specifies if the result should be normalized before being returned.
Vector4¶
Provides functions for creating and manipulating 4D vectors.