User talk:Neo: Difference between revisions

User talk:Neo (view source)

Revision as of 03:10, 17 April 2013

2,128 bytes added , 17 April 2013

added a possible solution about quaternions question

TwinkerTinker

7

edits

@@ Line 250: / Line 250: @@
 :::::Not to say that this is the only problem but... you're .dae files for left and right are identical :) [[User:Neo|Neo]]
 ::::::"The Make rotation keys continuous"is working great, no problems.  Except for the stupid user error with the Striker's walk... lol [[User:EdT|EdT]]
+::::::: Googled a possible solution and fitted it to one method. I have already checker it for some quaternions, which should result in euler angles, which contains values greater than 180 degrees, and it works fine. Here it is:
+    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;
+        Func<float, float> NormalizeAngle = new Func<float, float>(angle =>
+        {
+            while (angle > 360)
+                angle -= 360;
+            while (angle < 0)
+                angle += 360;
+            return angle;
+        });
+        Func<Vector3,Vector3> NormalizeAngles = new Func<Vector3,Vector3>(angles =>
+        {
+            angles.x = NormalizeAngle(angles.x);
+            angles.y = NormalizeAngle(angles.y);
+            angles.z = NormalizeAngle(angles.z);
+            return angles;
+        } );
+        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);
+    }
+p.s. sorry, not found any code tags or something like that.
+[[User:TwinkerTinker|6opoDuJIo]]
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