Maybe it's something we've fixed? I added your code:
Quaternion qNewOrientation;
Vector axis;
float angle;
AngleQuaternion( QAngle(0,90,0), qNewOrientation );
QuaternionAxisAngle( qNewOrientation, axis, angle );
Msg("Q:Axis: %.2f %.2f %.2f :: %.3f\n", VectorExpand(axis),
angle );
// If I pass QAngle(0,90,0) I will get 0.707106 or 90 angle
AngleQuaternion( QAngle(0,270,0), qNewOrientation );
QuaternionAxisAngle( qNewOrientation, axis, angle );
Msg("Q:Axis: %.2f %.2f %.2f :: %.3f\n", VectorExpand(axis),
angle );
// If I pass QAngle(0,270,0) I also get 0.707106 or 90 angle
And I get these results:
Q:Axis: 0.00 0.00 1.00 :: 90.000
Q:Axis: -0.00 0.00 1.00 :: -90.000
But I'm running the orange box sdk.
Here's the code for QuaternionAxisAngle()
void QuaternionAxisAngle( const Quaternion &q, Vector &axis, float
&angle )
{
angle = RAD2DEG(2 * acos(q.w));
if ( angle > 180 )
{
angle -= 360;
}
axis.x = q.x;
axis.y = q.y;
axis.z = q.z;
VectorNormalize( axis );
}
Is that the same code you're using?
Jay
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Joel R.
Sent: Monday, October 01, 2007 3:06 AM
To: hlcoders
Subject: [hlcoders] Quaternion to AxisAngle
--
[ Picked text/plain from multipart/alternative ]
I'm having a problem getting the correct angle. I seem to be stuck
getting
an angle between 0 and 180, due to the W value always being 0.0 to 1.0
and
not -1.0 to 1.0.
---CODE---
------------------------------------------------------------------------
----------------
Quaternion qNewOrientation;
Vector axis;
float angle;
AngleQuaternion( m_angSpawnAngle, qNewOrientation );
QuaternionAxisAngle( qNewOrientation, axis, angle );
------------------------------------------------------------------------
----------------
If I pass QAngle(0,90,0) I will get 0.707106 or 90 angle
If I pass QAngle(0,270,0) I also get 0.707106 or 90 angle
The latter is suppose to be negative. When I revert the quaternion back
to
a QAngle it gets the orientation correctly.
The formula QuaternionAxisAngle uses is correct because websites show
the
same algorithm used.
Anyone out there familiar with Quaternions know how I could possibly
solve
this? Thanks in advance!
--
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