Difference between revisions of "LlAxes2Rot"

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|p3_type=vector|p3_name=up
|p3_type=vector|p3_name=up
|return_text=that is defined by the 3 coordinate axes
|return_text=that is defined by the 3 coordinate axes
|notes=Technically, only the first two vectors are needed to define this rotation, which can be done by calling:
|notes=Technically, only the first two vectors are needed to define this rotation, which can be done by calling any of these:
<pre>llAxes2Rot(fwd, left, fwd % left);</pre>
<source lang="lsl2">llAxes2Rot(fwd, left, fwd % left);
llAxes2Rot(left % up, left, up);
llAxes2Rot(fwd, up % fwd, up);</source>
|spec
|spec
|caveats
|caveats
|examples=<lsl>
|examples=<source lang="lsl2">default
default
{
{
     state_entry()
     state_entry()
     {
     {
         vector i = < 1.0, 0.0, 0.0>;
         vector i = < 1.0, 0.0, 0.0>;
         vector j = < 0.0, 1.0, 0.0>;
         vector j = < 0.0, 1.0, 0.0>;
         vector k = < 0.0, 0.0, 1.0>;
         vector k = < 0.0, 0.0, 1.0>;


         rotation rot = llAxes2Rot( j, -i, k );
         rotation rot = llAxes2Rot( j, -i, k );
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         llSay(0, (string) (llRot2Euler(rot) * RAD_TO_DEG) );
         llSay(0, (string) (llRot2Euler(rot) * RAD_TO_DEG) );
     }
     }
}</lsl>
}</source>


This script displays:
This script displays:
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|also_functions
|also_functions
|also_events
|also_events
|also_tests
|also_tests=
{{LSL_DefineRow||[[User:Dora_Gustafson/llAxes2Rot_right_and_wrong|Visual illustration]]|Importance of mutually orthogonal unit vectors}}
|also_articles
|also_articles
|cat1=Math/3D
|cat1=Math/3D
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|cat3
|cat3
|cat4
|cat4
|haiku={{Haiku|quaternions rule|the whole world spins at your whim|or crashes and burns}}
}}
}}

Latest revision as of 05:10, 7 March 2016

Summary

Function: rotation llAxes2Rot( vector fwd, vector left, vector up );

Returns a rotation that is defined by the 3 coordinate axes

• vector fwd
• vector left
• vector up

All three vectors must be mutually orthogonal unit vectors.

Examples

default
{
    state_entry()
    {
        vector i = < 1.0, 0.0, 0.0>;
        vector j = < 0.0, 1.0, 0.0>;
        vector k = < 0.0, 0.0, 1.0>;

        rotation rot = llAxes2Rot( j, -i, k );

        llSay(0, (string) (llRot2Euler(rot) * RAD_TO_DEG) );
    }
}

This script displays:

  Object: <-0.00000, 0.00000, 90.00000>
which shows that (j, -i, k) is obtained by rotating (i, j, k) 90 degrees around z direction.

Notes

Technically, only the first two vectors are needed to define this rotation, which can be done by calling any of these:

llAxes2Rot(fwd, left, fwd % left);
llAxes2Rot(left % up, left, up);
llAxes2Rot(fwd, up % fwd, up);

Deep Notes

Search JIRA for related Issues

Tests

•  Visual illustration Importance of mutually orthogonal unit vectors

Signature

function rotation llAxes2Rot( vector fwd, vector left, vector up );

Haiku

quaternions rule
the whole world spins at your whim
or crashes and burns