コード例 #1
0
ファイル: test.py プロジェクト: kms70847/Animation
def lies_behind(p, poly):
    #draw a line from the viewer's position to p, and see if it intersects the plane formed by poly.
    #formula courtesy of https://en.wikipedia.org/wiki/Line%E2%80%93plane_intersection
    a,b,c = poly
    n = cross_product(b-a, c-a)
    p0 = a
    l = Point(0,0,1)
    l0 = p

    if dot_product(l,n) == 0: 
        #I think this only happens when the poly is viewed edge-on.
        return False
    d = dot_product(p0 - l0, n) / dot_product(l,n)
    return d < 0
コード例 #2
0
def reflect_speeds(normal_vector, v1_vector, v2_vector, m_1, m_2):
    """
        TODO
        """
    v1_eff = geometry.dot_product(normal_vector, v1_vector)
    v2_eff = geometry.dot_product(normal_vector, v2_vector)
    new_v1_eff, new_v2_eff = elastic_collision(v1_eff, -v2_eff, m_1, m_2)

    new_v1_eff = geometry.vector_product(normal_vector, new_v1_eff)
    new_v2_eff = geometry.vector_product(normal_vector, new_v2_eff)

    v1_perpendicular = geometry.components(normal_vector, v1_vector)[1]
    v2_perpendicular = geometry.components(normal_vector, v2_vector)[1]

    new_v1_vector = geometry.vector_diff(v1_perpendicular, new_v1_eff)
    new_v2_vector = geometry.vector_sum(v2_perpendicular, new_v2_eff)

    return (new_v1_vector[0], new_v1_vector[1], new_v2_vector[0],
            new_v2_vector[1])
コード例 #3
0
ファイル: physics.py プロジェクト: erhuabushuo/yapyg
def reflect_speeds(normal_vector, v1_vector, v2_vector, m_1, m_2):
        """
        TODO
        """
        v1_eff = geometry.dot_product(normal_vector, v1_vector)
        v2_eff = geometry.dot_product(normal_vector, v2_vector)
        new_v1_eff, new_v2_eff = elastic_collision(v1_eff, -v2_eff, m_1, m_2)

        new_v1_eff = geometry.vector_product(normal_vector, new_v1_eff)
        new_v2_eff = geometry.vector_product(normal_vector, new_v2_eff)

        v1_perpendicular = geometry.components(normal_vector, v1_vector)[1]
        v2_perpendicular = geometry.components(normal_vector, v2_vector)[1]

        new_v1_vector = geometry.vector_diff(v1_perpendicular, new_v1_eff)
        new_v2_vector = geometry.vector_sum(v2_perpendicular, new_v2_eff)

        return (new_v1_vector[0], new_v1_vector[1],
                new_v2_vector[0], new_v2_vector[1])
コード例 #4
0
ファイル: test.py プロジェクト: kms70847/Animation
def line_segment_intersection(a,b,c,d):
    #a line can be expressed as the set of points p for which
    #(p - p0) dot n = 0
    #where p0 is a point on the line and n is a normal vector to the line.
    #the vector equation for a line segment is
    #p = f*c + (1-f)*d = f*c - f*d + d = f*(c-d) + d
    #where f is a number between 0 and 1 inclusive.
    #
    #(f*(c-d) + d - p0) dot n = 0
    #((f*(c-d)) dot n) - ((p0 - d) dot n) = 0
    #((f*(c-d)) dot n) = ((p0 - d) dot n)
    #f*((c-d) dot n) = ((p0 - d) dot n)
    #f = ((p0 - d) dot n) / ((c-d) dot n)
    p0 = a
    n = exp(1, (a-b).angle() + math.radians(90))
    f = dot_product(p0-d, n) / dot_product(c-d, n)
    if 0 <= f <= 1:
        return (c+d)*f - d
    return None
コード例 #5
0
 def test_dot_product(self):
     self.assertEqual(geometry.dot_product([1, 2, 1], [1, 1, 2]), 5)
コード例 #6
0
ファイル: test.py プロジェクト: kms70847/Animation
def angle_3d(a,b):
    return math.acos(dot_product(a,b) / (a.magnitude() * b.magnitude()))