Difference between revisions of "LlVecMag"

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m (Replaced old <LSL> block with <source lang="lsl2">)
 
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{{LSLFunctionAll
{{LSL_Function
|func=llVecMag
|func=llVecMag
|func_id=12
|func_id=12|func_sleep=0.0|func_energy=10.0
|func_sleep=0.0
|func_energy=10.0
|func_footnote
|func_footnote
|p1_type=vector
|p1_type=vector|p1_name=vec|p1_desc
|p1_name=vec
|p1_desc
|p2_type|p2_name|p2_desc
|p3_type|p3_name|p3_desc
|p4_type|p4_name|p4_desc
|p5_type|p5_name|p5_desc
|p6_type|p6_name|p6_desc
|p7_type|p7_name|p7_desc
|p8_type|p8_name|p8_desc
|p9_type|p9_name|p9_desc
|p10_type|p10_name|p10_desc
|p11_type|p11_name|p11_desc
|p12_type|p12_name|p12_desc
|return_type=float
|return_type=float
|return_text=that is the magnitude of the vector (the distance from vec to <0.0, 0.0, 0.0>).
|return_text=that is the magnitude of the vector (the undirected non-negative distance from {{LSLP|vec}} to {{LSL VR|0.0|0.0|0.0}}).
|spec
|spec
|caveats
|caveats
|examples=
|examples=
<lsl>
<source lang="lsl2">
default {
default {
     state_entry()
     state_entry()
     {
     {
         vector input = <1.0,2.0,3.0>;
         vector input = <1.0,2.0,3.0>;
         llSay(0,"The magnitude of "+(string)input+" is: "+(string)llVecMag(input) );
         llSay(0,"The magnitude of "+(string)input+" is "+(string)llVecMag(input) + ".");
     }
     }
}
}
</lsl>
</source>
|helpers
|helpers
|related={{LSLG|llVecNorm}}<br/>{{LSLG|llVecDist}}
|also_functions=
|also
{{LSL DefineRow||[[llVecNorm]]|The vector normal}}
|notes
{{LSL DefineRow||[[llVecDist]]|The distance between two vectors}}
|also_events
|also_tests
|also_articles
|notes=
* Mathematically the formula for vector magnitude is
**  <code>[[llSqrt]](vec.x * vec.x + vec.y * vec.y + vec.z * vec.z)</code>
* Knowing this, there are ways to circumvent llVecMag for more efficient code.
** vec*vec < 16.0 is over twice as fast as llVecMag(vec) < 4.0.
** vec*vec < (dist*dist) is about twice as fast as llVecMag(vec) < dist.
** This can work in many other ways, too, with other comparisons.
|permission
|negative_index
|cat1=Math/3D
|cat2=Vector
|cat3
|cat4
}}
}}
[[Category:LSL_Functions]]
[[Category:LSL_Math]]

Latest revision as of 12:00, 22 January 2015

Summary

Function: float llVecMag( vector vec );

Returns a float that is the magnitude of the vector (the undirected non-negative distance from vec to <0.0, 0.0, 0.0>).

• vector vec

Examples

default {
    state_entry()
    {
        vector input = <1.0,2.0,3.0>;
        llSay(0,"The magnitude of "+(string)input+" is "+(string)llVecMag(input) + ".");
    }
}

Notes

  • Mathematically the formula for vector magnitude is
    • llSqrt(vec.x * vec.x + vec.y * vec.y + vec.z * vec.z)
  • Knowing this, there are ways to circumvent llVecMag for more efficient code.
    • vec*vec < 16.0 is over twice as fast as llVecMag(vec) < 4.0.
    • vec*vec < (dist*dist) is about twice as fast as llVecMag(vec) < dist.
    • This can work in many other ways, too, with other comparisons.

See Also

Functions

•  llVecNorm The vector normal
•  llVecDist The distance between two vectors

Deep Notes

Search JIRA for related Issues

Signature

function float llVecMag( vector vec );