/**
* graphene_quaternion_slerp:
* @a: a #graphene_quaternion_t
* @b: a #graphene_quaternion_t
* @factor: the linear interpolation factor
* @res: (out caller-allocates): return location for the interpolated
* quaternion
*
* Interpolates between the two given quaternions using a spherical
* linear interpolation, or [SLERP](http://en.wikipedia.org/wiki/Slerp),
* using the given interpolation @factor.
*
* Since: 1.0
*/
void
graphene_quaternion_slerp (const graphene_quaternion_t *a,
const graphene_quaternion_t *b,
float factor,
graphene_quaternion_t *res)
{
float theta, r_sin_theta, right_v, left_v, dot;
graphene_simd4f_t v_a, v_b, left, right, sum;
v_a = graphene_simd4f_init (a->x, a->y, a->z, a->w);
v_b = graphene_simd4f_init (b->x, b->y, b->z, b->w);
dot = CLAMP (graphene_simd4f_get_x (graphene_simd4f_dot4 (v_a, v_b)), -1.f, 1.f);
if (dot == 1.f)
{
*res = *a;
return;
}
theta = acos (dot);
r_sin_theta = 1.f / sqrtf (1.f - dot * dot);
right_v = sinf (factor * theta) * r_sin_theta;
left_v = cosf (factor * theta) - dot * right_v;
left = graphene_simd4f_init (a->x, a->y, a->z, a->w);
right = graphene_simd4f_init (b->x, b->y, b->z, b->w);
left = graphene_simd4f_mul (left, graphene_simd4f_splat (left_v));
right = graphene_simd4f_mul (right, graphene_simd4f_splat (right_v));
sum = graphene_simd4f_add (left, right);
graphene_quaternion_init_from_simd4f (res, sum);
}
/**
* graphene_vec3_add:
* @a: a #graphene_vec3_t
* @b: a #graphene_vec3_t
* @res: (out caller-allocates): return location for the resulting vector
*
* Adds each component of the two given vectors.
*
* Since: 1.0
*/
void
graphene_vec3_add (const graphene_vec3_t *a,
const graphene_vec3_t *b,
graphene_vec3_t *res)
{
res->value = graphene_simd4f_add (a->value, b->value);
}
/**
* graphene_vec3_get_xyz1:
* @v: a #graphene_vec3_t
* @res: (out caller-allocates): return location for the vector
*
* Converts a #graphene_vec3_t in a #graphene_vec4_t using 1.0
* as the value for the fourth component of the resulting vector.
*
* Since: 1.0
*/
void
graphene_vec3_get_xyz1 (const graphene_vec3_t *v,
graphene_vec4_t *res)
{
res->value = graphene_simd4f_add (graphene_simd4f_zero_w (v->value),
graphene_simd4f_init (0.f, 0.f, 0.f, 1.f));
}
/**
* graphene_matrix_skew_yz:
* @m: a #graphene_matrix_t
* @factor: skew factor
*
* Adds a skew of @factor on the Y and Z axis to the given matrix.
*
* Since: 1.0
*/
void
graphene_matrix_skew_yz (graphene_matrix_t *m,
float factor)
{
graphene_simd4f_t m_y, m_z;
m_y = m->value.y;
m_z = m->value.z;
m->value.z = graphene_simd4f_add (m_z, graphene_simd4f_mul (m_y, graphene_simd4f_splat (factor)));
}
/**
* graphene_matrix_skew_xy:
* @m: a #graphene_matrix_t
* @factor: skew factor
*
* Adds a skew of @factor on the X and Y axis to the given matrix.
*
* Since: 1.0
*/
void
graphene_matrix_skew_xy (graphene_matrix_t *m,
float factor)
{
graphene_simd4f_t m_x, m_y;
m_x = m->value.x;
m_y = m->value.y;
m->value.y = graphene_simd4f_add (m_y, graphene_simd4f_mul (m_x, graphene_simd4f_splat (factor)));
}
void
graphene_matrix_skew_xz (graphene_matrix_t *m,
float factor)
{
graphene_simd4f_t m_x, m_z;
g_return_if_fail (m != NULL);
m_x = m->value.x;
m_z = m->value.z;
m->value.z = graphene_simd4f_add (m_z, graphene_simd4f_mul (m_x, graphene_simd4f_splat (factor)));
}
/**
* graphene_simd4f_add:
* @a: a #graphene_simd4f_t
* @b: a #graphene_simd4f_t
*
* Creates a new #graphene_simd4f_t vector where each
* component is the sum of the respective components
* in @a and @b.
*
* |[<!-- lanugage="plain" -->
* {
* .x = a.x + b.x,
* .y = a.y + b.y,
* .z = a.z + b.z,
* .w = a.w + b.w
* }
* ]|
*
* Returns: the sum vector
*
* Since: 1.0
*/
graphene_simd4f_t
(graphene_simd4f_add) (const graphene_simd4f_t a,
const graphene_simd4f_t b)
{
return graphene_simd4f_add (a, b);
}