GLUSAPI GLUSvoid GLUSAPIENTRY glusQuaternionGetEulerRzRyRxf(GLUSfloat angles[3], const GLUSfloat quaternion[4])
{
GLUSfloat x = quaternion[0];
GLUSfloat y = quaternion[1];
GLUSfloat z = quaternion[2];
GLUSfloat w = quaternion[3];
GLUSfloat f00 = 1.0f - 2.0f * y * y - 2.0f * z * z;
GLUSfloat f20 = 2.0f * x * z - 2.0f * w * y;
if (f00 != 0.0f)
{
GLUSfloat f10 = 2.0f * x * y + 2.0f * w * z;
GLUSfloat f21 = 2.0f * y * z + 2.0f * w * x;
GLUSfloat f22 = 1.0f - 2.0f * x * x - 2.0f * y * y;
angles[0] = glusMathRadToDegf(atan2f(f21, f22));
angles[1] = glusMathRadToDegf(asinf(-f20));
angles[2] = glusMathRadToDegf(atan2f(f10, f00));
}
else
{
GLUSfloat f01 = 2.0f * x * y - 2.0f * w * z;
GLUSfloat f11 = 1.0f - 2.0f * x * x - 2.0f * z * z;
angles[0] = glusMathRadToDegf(atan2f(f01, f11));
angles[1] = glusMathRadToDegf(asinf(-f20));
angles[2] = 0.0f;
}
}
GLUSboolean GLUSAPIENTRY GLUSAPIENTRY glusQuaternionGetEulerRzRyRxf(GLUSfloat angles[3], const GLUSfloat quaternion[4])
{
GLUSfloat x = quaternion[0];
GLUSfloat y = quaternion[1];
GLUSfloat z = quaternion[2];
GLUSfloat w = quaternion[3];
GLUSfloat f00 = 1.0f - 2.0f * y * y - 2.0f * z * z;
GLUSfloat f10 = 2.0f * x * y + 2.0f * w * z;
GLUSfloat f20 = 2.0f * x * z - 2.0f * w * y;
GLUSfloat f01 = 2.0f * x * y - 2.0f * w * z;
GLUSfloat f11 = 1.0f - 2.0f * x * x - 2.0f * z * z;
GLUSfloat f21 = 2.0f * y * z + 2.0f * w * x;
GLUSfloat f22 = 1.0f - 2.0f * x * x - 2.0f * y * y;
if (!(f21 == 0.0f && f22 == 0.0f) && !(f10 == 0.0f && f00 == 0.0f))
{
angles[0] = glusMathRadToDegf(atan2f(f21, f22));
angles[1] = glusMathRadToDegf(asinf(-f20));
angles[2] = glusMathRadToDegf(atan2f(f10, f00));
}
else if (!(f01 == 0.0f && f11 == 0.0f))
{
angles[0] = glusMathRadToDegf(atan2f(f01, f11));
angles[1] = glusMathRadToDegf(asinf(-f20));
angles[2] = 0.0f;
}
else
{
return GLUS_FALSE;
}
return GLUS_TRUE;
}
