llAxisAngle2Rot

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Revision as of 22:28, 15 February 2014 by Rob Niosaki (talk | contribs)
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Summary

Function: rotation llAxisAngle2Rot( vector axis, float angle );
0.0 Forced Delay
10.0 Energy

Returns a rotation that is a generated angle about axis

• vector axis
• float angle expressed in radians.

axis need not be normalized, only the direction is important.

angle need to be between the value 0<angle<PI (higher values than PI lead to 2*PI-angle) , because a rotation is not really a rotation (it is more of a rigid motion/mirroring) ,the final destination is the rotation. (in other words: it doesn't matter wether you rotate left by 90 degrees or right by 270 degrees it will return the same rotation)

Examples

<lsl>default {

   state_entry()
   {
       vector axis = <0.0, 0.0, 1.0>;
       float angle = 90.0 * DEG_TO_RAD;
       rotation rot = llAxisAngle2Rot(axis, angle);
       vector euler = llRot2Euler(rot) * RAD_TO_DEG;
       llOwnerSay((string) euler);
       //Says <0.0, 0.0, 90.0> since it is rotating 90 degrees on the Z axis caused by the 1.0 placed in the Z vector spot. 
   }
}</lsl>

See Also

Functions

•  llRot2Angle
•  llRot2Axis

Deep Notes

<lsl>rotation llAxisAngle2Rot( vector axis, float angle ) {

   axis = llVecNorm( axis ) * llSin( angle/2 );
   return <axis.x, axis.y, axis.z, llCos( angle/2 )>;

}</lsl>

Signature

function rotation llAxisAngle2Rot( vector axis, float angle );