我使用了两个例子（也来自这个网站），但结果与Unity说的结果不一样。
Quaternion.Euler和.eulerAngles是Unity功能。 FromQ不执行奇点检查，FromQ2会这样做。
结果：
eulers = (100,55,-11):
Quaternion.Euler(eulers) == (0.6, 0.4, -0.4, 0.5)
ToQ(eulers)); == (0.5, -0.4, 0.2, 0.7) // 0.5, -0.4 right but in wrong order
FromQ(ToQ(eulers)) == (55.0, 100.0, -11.0)
FromQ2(ToQ(eulers)) == (-55.5, -6.3, 71.0) // something right
Quaternion.Euler(eulers).eulerAngles == (80.0, 235.0, 169.0)
FromQ2(Quaternion.Euler(eulers)) == (65.8, 1.9, 99.8)
ToQ(eulers).eulerAngles == (70.0, 286.9, 341.4)
FromQ(Quaternion.Euler(eulers)) == (-65.8, 76.0, 4.6)
It must be:
FromQ() = FromQ2() = .eulerAngles,
ToQ() = Quaternion.Euler()
代码在这里：http://pastebin.ru/eAlTHdYf
任何人都可以更正此代码吗？我需要的代码将返回与Unity函数返回的值相同的值。
以下是固定代码：http://pastebin.com/riRLRvch。 这两个功能（FromQ和ToQ）都运行良好。但我有一个奇点问题。它无法正确检测奇点。
For example (90, 0, 50) in quaternion is (0.6, -0.3, 0.3, 0.6).
test = x * y + z * w = 0 (must be close to 0.5 or -0.5)
FromQ无法计算出正确的结果，所以我们在这里有奇点。 （90,50,0） - （0.6,0.3，-0.3,0.6）相同。
我只看到一个解决方案 - 将“test”计算为xw-yz。但我不确定这是对的。
如何解决？
答案 0 :(得分：7)
我找到了解决方案
public static Quaternion ToQ (Vector3 v)
{
return ToQ (v.y, v.x, v.z);
}
public static Quaternion ToQ (float yaw, float pitch, float roll)
{
yaw *= Mathf.Deg2Rad;
pitch *= Mathf.Deg2Rad;
roll *= Mathf.Deg2Rad;
float rollOver2 = roll * 0.5f;
float sinRollOver2 = (float)Math.Sin ((double)rollOver2);
float cosRollOver2 = (float)Math.Cos ((double)rollOver2);
float pitchOver2 = pitch * 0.5f;
float sinPitchOver2 = (float)Math.Sin ((double)pitchOver2);
float cosPitchOver2 = (float)Math.Cos ((double)pitchOver2);
float yawOver2 = yaw * 0.5f;
float sinYawOver2 = (float)Math.Sin ((double)yawOver2);
float cosYawOver2 = (float)Math.Cos ((double)yawOver2);
Quaternion result;
result.w = cosYawOver2 * cosPitchOver2 * cosRollOver2 + sinYawOver2 * sinPitchOver2 * sinRollOver2;
result.x = cosYawOver2 * sinPitchOver2 * cosRollOver2 + sinYawOver2 * cosPitchOver2 * sinRollOver2;
result.y = sinYawOver2 * cosPitchOver2 * cosRollOver2 - cosYawOver2 * sinPitchOver2 * sinRollOver2;
result.z = cosYawOver2 * cosPitchOver2 * sinRollOver2 - sinYawOver2 * sinPitchOver2 * cosRollOver2;
return result;
}
public static Vector3 FromQ2 (Quaternion q1)
{
float sqw = q1.w * q1.w;
float sqx = q1.x * q1.x;
float sqy = q1.y * q1.y;
float sqz = q1.z * q1.z;
float unit = sqx + sqy + sqz + sqw; // if normalised is one, otherwise is correction factor
float test = q1.x * q1.w - q1.y * q1.z;
Vector3 v;
if (test>0.4995f*unit) { // singularity at north pole
v.y = 2f * Mathf.Atan2 (q1.y, q1.x);
v.x = Mathf.PI / 2;
v.z = 0;
return NormalizeAngles (v * Mathf.Rad2Deg);
}
if (test<-0.4995f*unit) { // singularity at south pole
v.y = -2f * Mathf.Atan2 (q1.y, q1.x);
v.x = -Mathf.PI / 2;
v.z = 0;
return NormalizeAngles (v * Mathf.Rad2Deg);
}
Quaternion q = new Quaternion (q1.w, q1.z, q1.x, q1.y);
v.y = (float)Math.Atan2 (2f * q.x * q.w + 2f * q.y * q.z, 1 - 2f * (q.z * q.z + q.w * q.w)); // Yaw
v.x = (float)Math.Asin (2f * (q.x * q.z - q.w * q.y)); // Pitch
v.z = (float)Math.Atan2 (2f * q.x * q.y + 2f * q.z * q.w, 1 - 2f * (q.y * q.y + q.z * q.z)); // Roll
return NormalizeAngles (v * Mathf.Rad2Deg);
}
static Vector3 NormalizeAngles (Vector3 angles)
{
angles.x = NormalizeAngle (angles.x);
angles.y = NormalizeAngle (angles.y);
angles.z = NormalizeAngle (angles.z);
return angles;
}
static float NormalizeAngle (float angle)
{
while (angle>360)
angle -= 360;
while (angle<0)
angle += 360;
return angle;
}
答案 1 :(得分：3)
这个问题差不多有三年了，但我需要相同的代码，这里发布的代码似乎不正确，所以我调整了它们并找到了这个：
public static Quaternion Euler(float yaw, float pitch, float roll) {
yaw*=Mathf.Deg2Rad;
pitch*=Mathf.Deg2Rad;
roll*=Mathf.Deg2Rad;
double yawOver2 = yaw * 0.5f;
float cosYawOver2 = (float)System.Math.Cos(yawOver2);
float sinYawOver2 = (float)System.Math.Sin(yawOver2);
double pitchOver2 = pitch * 0.5f;
float cosPitchOver2 = (float)System.Math.Cos(pitchOver2);
float sinPitchOver2 = (float)System.Math.Sin(pitchOver2);
double rollOver2 = roll * 0.5f;
float cosRollOver2 = (float)System.Math.Cos(rollOver2);
float sinRollOver2 = (float)System.Math.Sin(rollOver2);
Quaternion result;
result.w = cosYawOver2 * cosPitchOver2 * cosRollOver2 + sinYawOver2 * sinPitchOver2 * sinRollOver2;
result.x = sinYawOver2 * cosPitchOver2 * cosRollOver2 + cosYawOver2 * sinPitchOver2 * sinRollOver2;
result.y = cosYawOver2 * sinPitchOver2 * cosRollOver2 - sinYawOver2 * cosPitchOver2 * sinRollOver2;
result.z = cosYawOver2 * cosPitchOver2 * sinRollOver2 - sinYawOver2 * sinPitchOver2 * cosRollOver2;
return result;
}
根据一些快速测试，这与Quaternion.Euler 100％
匹配答案 2 :(得分：0)
这可能只值得部分答案，但这里是“ToQ（）= Quaternion.Euler（）”：
public static Quaternion ToQ(Vector3 v)
{
return ToQ(v.y,v.x,v.z);
}
public static Quaternion ToQ(float yaw, float pitch, float roll)
{
yaw*=Mathf.Deg2Rad;
pitch*=Mathf.Deg2Rad;
roll*=Mathf.Deg2Rad;
float rollOver2 = roll * 0.5f;
float sinRollOver2 = (float)Math.Sin((double)rollOver2);
float cosRollOver2 = (float)Math.Cos((double)rollOver2);
float pitchOver2 = pitch * 0.5f;
float sinPitchOver2 = (float)Math.Sin((double)pitchOver2);
float cosPitchOver2 = (float)Math.Cos((double)pitchOver2);
float yawOver2 = yaw * 0.5f;
float sinYawOver2 = (float)Math.Sin((double)yawOver2);
float cosYawOver2 = (float)Math.Cos((double)yawOver2);
Quaternion result;
result.w = cosYawOver2 * cosPitchOver2 * cosRollOver2 + sinYawOver2 * sinPitchOver2 * sinRollOver2;
result.x = cosYawOver2 * sinPitchOver2 * cosRollOver2 + sinYawOver2 * cosPitchOver2 * sinRollOver2;
result.y = sinYawOver2 * cosPitchOver2 * cosRollOver2 - cosYawOver2 * sinPitchOver2 * sinRollOver2;
result.z = cosYawOver2 * cosPitchOver2 * sinRollOver2 - sinYawOver2 * sinPitchOver2 * cosRollOver2;
return result;
}
你问题的'FromQ'部分是另一回事。欧拉角comparison is a pain in the behind。
答案 3 :(得分：0)
这是我的解决方案。这非常接近Unity的Quaternion.Euler和quaternion.eulerAngles。差异足够小，以至于对于任何应用程序都不重要。
public static Vector3 QuaternionToEuler(Quaternion q)
{
Vector3 euler;
// if the input quaternion is normalized, this is exactly one. Otherwise, this acts as a correction factor for the quaternion's not-normalizedness
float unit = (q.x * q.x) + (q.y * q.y) + (q.z * q.z) + (q.w * q.w);
// this will have a magnitude of 0.5 or greater if and only if this is a singularity case
float test = q.x * q.w - q.y * q.z;
if (test > 0.4995f * unit) // singularity at north pole
{
euler.x = Mathf.PI / 2;
euler.y = 2f * Mathf.Atan2(q.y, q.x);
euler.z = 0;
}
else if (test < -0.4995f * unit) // singularity at south pole
{
euler.x = -Mathf.PI / 2;
euler.y = -2f * Mathf.Atan2(q.y, q.x);
euler.z = 0;
}
else // no singularity - this is the majority of cases
{
euler.x = Mathf.Asin(2f * (q.w * q.x - q.y * q.z));
euler.y = Mathf.Atan2(2f * q.w * q.y + 2f * q.z * q.x, 1 - 2f * (q.x * q.x + q.y * q.y));
euler.z = Mathf.Atan2(2f * q.w * q.z + 2f * q.x * q.y, 1 - 2f * (q.z * q.z + q.x * q.x));
}
// all the math so far has been done in radians. Before returning, we convert to degrees...
euler *= Mathf.Rad2Deg;
//...and then ensure the degree values are between 0 and 360
euler.x %= 360;
euler.y %= 360;
euler.z %= 360;
return euler;
}
public static Quaternion EulerToQuaternion(Vector3 euler)
{
float xOver2 = euler.x * Mathf.Deg2Rad * 0.5f;
float yOver2 = euler.y * Mathf.Deg2Rad * 0.5f;
float zOver2 = euler.z * Mathf.Deg2Rad * 0.5f;
float sinXOver2 = Mathf.Sin(xOver2);
float cosXOver2 = Mathf.Cos(xOver2);
float sinYOver2 = Mathf.Sin(yOver2);
float cosYOver2 = Mathf.Cos(yOver2);
float sinZOver2 = Mathf.Sin(zOver2);
float cosZOver2 = Mathf.Cos(zOver2);
Quaternion result;
result.x = cosYOver2 * sinXOver2 * cosZOver2 + sinYOver2 * cosXOver2 * sinZOver2;
result.y = sinYOver2 * cosXOver2 * cosZOver2 - cosYOver2 * sinXOver2 * sinZOver2;
result.z = cosYOver2 * cosXOver2 * sinZOver2 - sinYOver2 * sinXOver2 * cosZOver2;
result.w = cosYOver2 * cosXOver2 * cosZOver2 + sinYOver2 * sinXOver2 * sinZOver2;
return result;
}