""" Test suite for affine transforms.

    :Author:      Eric Jones, Enthought, Inc., eric@enthought.com
    :Copyright:   Space Telescope Science Institute
    :License:     BSD Style

    So far, this is mainly a "smoke test" suite to make sure
    nothing is obviously wrong.  It relies on the transforms
    being stored in 3x3 array.
"""


import unittest
import sys
from numpy import arctan2, alltrue, array, identity, dot, ravel, allclose, pi,cos

from kiva import affine

class AffineConstructorsTestCase(unittest.TestCase):

    def test_identity(self):
        i = affine.affine_identity()
        self.assertTrue(allclose(identity(3), i))

    def test_from_values(self):
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        mat = affine.affine_from_values(a,b,c,d,tx,ty)
        desired = array([[a,  b, 0],
                         [c,  d, 0],
                         [tx,ty, 1]])
        assert(alltrue(ravel(mat)==ravel(desired)))

    def test_from_scale(self):
        transform = affine.affine_from_scale(5.,6.)
        pt1 = array([1.,1.,1.])
        actual = dot(pt1,transform)
        desired = pt1*array((5.,6.,1.))
        assert(alltrue( actual == desired ))

    def test_from_translation(self):
        transform = affine.affine_from_translation(5.,6.)
        pt1 = array([1.,1.,1.])
        actual = dot(pt1,transform)
        desired = pt1+array((5.,6.,0.))
        assert(alltrue( actual == desired ))

    def test_from_rotation(self):
        transform = affine.affine_from_rotation(pi/4.)
        pt1 = array([1.,0.,1.])
        actual = dot(pt1,transform)
        #cos_pi_4 = 0.70710678118654757
        cos_pi_4 = cos(pi/4.0)
        desired = array((cos_pi_4, cos_pi_4, 1.0))
        assert(alltrue( (actual - desired) < 1e-6 ))

class AffineOperationsTestCase(unittest.TestCase):
    """ Test are generally run by operating on a matrix and using
        it to transform a point.  We then transform the point using
        some known sequence of operations that should produce the
        same results.
    """

    def test_scale(self):
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        transform1 = affine.affine_from_values(a,b,c,d,tx,ty)
        transform2 = affine.scale(transform1,.5,1.5)
        pt1 = array([1.,-1.,1.])
        actual = dot(pt1,transform2)
        # this does the first transform and the scaling separately
        desired = dot(pt1,transform1) *array((.5,1.5,1.))
        assert(alltrue( (actual - desired) < 1e-6 ))

    def test_translate(self):
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        transform1 = affine.affine_from_values(a,b,c,d,tx,ty)
        translate_transform = array([[0,0,0],
                                     [0,0,0],
                                     [.5,1.5,1]])
        tot_transform = affine.translate(transform1,.5,1.5)
        pt1 = array([1.,-1.,1.])
        actual = dot(pt1,tot_transform)
        # this does the first transform and the translate separately
        desired = dot(dot(pt1,translate_transform),
                                 transform1)
        assert(alltrue( (actual - desired) < 1e-6 ))

    def test_rotate(self):
        a,b,c,d,tx,ty = 1.,0,0,1.,0,0
        transform1 = affine.affine_from_values(a,b,c,d,tx,ty)
        tot_transform = affine.rotate(transform1,pi/4)
        pt1 = array([1.,0.,1.])
        actual = dot(pt1,tot_transform)
        # this does the first transform and the translate separately
        cos_pi_4 = 0.70710678118654757
        desired = array((cos_pi_4,cos_pi_4,1.))
        assert(alltrue( (actual - desired) < 1e-6 ))

    def test_invert(self):
        """ An matrix times its inverse should produce the identity matrix
        """
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        transform1 = affine.affine_from_values(a,b,c,d,tx,ty)
        transform2 = affine.invert(transform1)
        desired = affine.affine_identity()
        actual = dot(transform2,transform1)
        assert(alltrue( (ravel(actual) - ravel(desired)) < 1e-6 ))

    def test_concat(self):
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        transform1 = affine.affine_from_values(a,b,c,d,tx,ty)
        a,b,c,d,tx,ty = 2,3,4,5,6,7
        transform2 = affine.affine_from_values(a,b,c,d,tx,ty)
        tot_transform = affine.concat(transform1,transform2)
        pt1 = array([1.,-1.,1.])
        actual = dot(pt1,tot_transform)
        # this does the first transform and the scaling separately
        desired = dot(dot(pt1,transform2),transform1)
        assert(alltrue( (actual - desired) < 1e-6 ))

class AffineInformationTestCase(unittest.TestCase):
    """ Test are generally run by operating on a matrix and using
        it to transform a point.  We then transform the point using
        some known sequence of operations that should produce the
        same results.
    """
    def test_is_identity(self):
        # a true case.
        m = affine.affine_identity()
        assert(affine.is_identity(m))
        # and a false one.
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        m = affine.affine_from_values(a,b,c,d,tx,ty)
        assert(not affine.is_identity(m))

    def test_affine_params(self):
        a,b,c,d,tx,ty = 1,2,3,4,5,6
        trans = affine.affine_from_values(a,b,c,d,tx,ty)
        aa,bb,cc,dd,txx,tyy = affine.affine_params(trans)
        assert( (a,b,c,d,tx,ty) == (aa,bb,cc,dd,txx,tyy))

    def test_trs_factor(self):
        trans = affine.affine_identity()
        trans = affine.translate(trans,5,5)
        trans = affine.rotate(trans,2.4)
        trans = affine.scale(trans,10,10)
        tx,ty,sx,sy,angle = affine.trs_factor(trans)
        assert( (tx,ty) == (5,5))
        assert( (sx,sy) == (10,10))
        assert( angle == 2.4)

class TransformPointsTestCase(unittest.TestCase):
    def test_transform_point(self):
        pt = array((1,1))
        ctm = affine.affine_identity()
        ctm = affine.translate(ctm,5,5)
        new_pt = affine.transform_point(ctm, pt)
        assert(alltrue(new_pt == array((6,6))))

        ctm = affine.rotate(ctm,pi)
        new_pt = affine.transform_point(ctm, pt)
        assert(sum(new_pt - array((4.,4.))) < 1e-15)

        ctm = affine.scale(ctm,10,10)
        new_pt = affine.transform_point(ctm, pt)
        assert(sum(new_pt - array((-5.,-5.))) < 1e-15)

    def test_transform_points(self):
        # not that thorough...
        pt = array(((1,1),))
        ctm = affine.affine_identity()
        ctm = affine.translate(ctm,5,5)
        new_pt = affine.transform_points(ctm, pt)
        assert(alltrue(new_pt[0] == array((6,6))))

        ctm = affine.rotate(ctm,pi)
        new_pt = affine.transform_points(ctm, pt)
        assert(sum(new_pt[0] - array((4.,4.))) < 1e-15)

        ctm = affine.scale(ctm,10,10)
        new_pt = affine.transform_points(ctm, pt)
        assert(sum(new_pt[0] - array((-5.,-5.))) < 1e-15)


if __name__ == "__main__":
    unittest.main()

