Difference between revisions of "LlRot2Left"
Omei Qunhua (talk | contribs) (Provide an example) |
Omei Qunhua (talk | contribs) m (As llRot2Fwd etc.) |
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|func=llRot2Left|sort=Rot2Left | |func=llRot2Left|sort=Rot2Left | ||
|return_type=vector|p1_type=rotation|p1_name=q | |return_type=vector|p1_type=rotation|p1_name=q | ||
|func_desc=Computes the orientation of the {{HoverText|local y-axis|left-direction of prim}} relative to | |func_desc=Computes the orientation of the {{HoverText|local y-axis|left-direction of prim}} relative to the parent (i.e. relative to the root prim or the world). | ||
|return_text=that is the left vector defined by {{LSLP|q}}, i.e. a unit vector pointing in the local positive Y direction | |return_text=that is the left vector defined by {{LSLP|q}}, i.e. a unit vector pointing in the local positive Y direction | ||
|spec=Mathematically equivalent to: | |spec=Mathematically equivalent to: | ||
<lsl>ret = llVecNorm(<0., 1., 0.> * q);</lsl> | <lsl>ret = llVecNorm(<0., 1., 0.> * q);</lsl> | ||
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<lsl> | <lsl> | ||
// Move an object 5 metres forwards along its own y axis, when touched, no matter how the object is oriented in world. | // Move an object 5 metres forwards along its own y axis, when touched, no matter how the object is oriented in world. | ||
// Works for a root or child prim | |||
default | default | ||
{ | { | ||
touch_start(integer total_number) | touch_start(integer total_number) | ||
{ | { | ||
vector v = llRot2Left( | vector v = llRot2Left( llGetLocalRot() ); | ||
llSetPos( | llSetPos( llGetLocalPos() + v * 5 ); | ||
} | } | ||
} | } | ||
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|also_events | |also_events | ||
|also_articles | |also_articles | ||
|notes | |notes=Can be useful to identify the orientation of the local {{Wikipedia|sagittal plane|sagittal-plane}} of the prim, since it's y-axis is always perpendicular to this local sagittal-plane. | ||
|cat1=Rotation | |cat1=Rotation | ||
|cat2 | |cat2 | ||
Revision as of 10:59, 6 December 2013
| LSL Portal | Functions | Events | Types | Operators | Constants | Flow Control | Script Library | Categorized Library | Tutorials |
Summary
Function: vector llRot2Left( rotation q );| 0.0 | Forced Delay |
| 10.0 | Energy |
Computes the orientation of the local y-axis relative to the parent (i.e. relative to the root prim or the world).
Returns a vector that is the left vector defined by q, i.e. a unit vector pointing in the local positive Y direction
| • rotation | q |
Specification
Mathematically equivalent to: <lsl>ret = llVecNorm(<0., 1., 0.> * q);</lsl> If q is known to be a unit quaternion then it can be simplified as: <lsl>ret = <0., 1., 0.> * q;</lsl> Keep in mind that object and agent rotations will always be unit quaternions. For example, <0.0, 1.0, 0.0>*llGetRot() is about 25-30% faster than llRot2Left(llGetRot()) depending on the VM used. If done often and at extremely fast rates, it can be advantageous to even save <0.0, 1.0, 0.0> to a local/global variable and reuse it.
Examples
<lsl> // Move an object 5 metres forwards along its own y axis, when touched, no matter how the object is oriented in world. // Works for a root or child prim default {
touch_start(integer total_number)
{
vector v = llRot2Left( llGetLocalRot() );
llSetPos( llGetLocalPos() + v * 5 );
}
}
</lsl>Notes
Can be useful to identify the orientation of the local 
sagittal-plane of the prim, since it's y-axis is always perpendicular to this local sagittal-plane.
See Also
Functions
| • | llRot2Up | |||
| • | llRot2Fwd | |||
| • | llRot2Axis | |||
| • | llRot2Angle |
Deep Notes
Signature |
|---|
function vector llRot2Left( rotation q ); |