Difference between revisions of "LlAtan2"

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m (Math error in the example script)
Line 22: Line 22:
     llOwnerSay("The arctangent of y divided by x is " + (string)llAtan2(num1, num2));
     llOwnerSay("The arctangent of y divided by x is " + (string)llAtan2(num1, num2));
   }
   }
}</lsl><lsl>//Function with input of a vector determining the position of a target and returning
//a string with the literal compass-direction of that target towards your position
//by Ramana Sweetwater 2009/01, any use allowed license :-)
string compass (vector target)
{
    vector me = llGetPos();
    float distance = llVecDist(me, target);
    list DIRS =["W","NW","N","NE","E","SE","S","SW","W"];
    return llList2String(DIRS,llCeil(4.5-((4*llAtan2((target.y-me.y)/distance,(target.x-me.x)/distance))/PI)));
}</lsl>
}</lsl>
|helpers
|helpers

Revision as of 10:05, 8 February 2009

Summary

Function: float llAtan2( float y, float x );
0.0 Forced Delay
10.0 Energy

Returns a float that is the "Wikipedia logo"arctangent2 of y, x.

• float y
• float x

Similar to the arctangent(y/x) except it utilizes the signs of x & y to determine the quadrant. Returns zero if x and y are zero.

Examples

<lsl>default {

 state_entry()
 {
   float num1 = llFrand(100.0);
   float num2 = llFrand(100.0);
   llOwnerSay("y = " + (string)num1);
   llOwnerSay("x = " + (string)num2);
   llOwnerSay("The arctangent of y divided by x is " + (string)llAtan2(num1, num2));
 }

}</lsl><lsl>//Function with input of a vector determining the position of a target and returning //a string with the literal compass-direction of that target towards your position //by Ramana Sweetwater 2009/01, any use allowed license :-)

string compass (vector target) {

   vector me = llGetPos();
   float distance = llVecDist(me, target);
   list DIRS =["W","NW","N","NE","E","SE","S","SW","W"];
   return llList2String(DIRS,llCeil(4.5-((4*llAtan2((target.y-me.y)/distance,(target.x-me.x)/distance))/PI)));
}</lsl>

See Also

Functions

• llSin llAsin sine & inverse Sine
• llCos llAcos cosine & inverse cosine
• llTan tangent

Articles

•  "Wikipedia logo"Atan2
•  "Wikipedia logo"Inverse_trigonometric_function

Deep Notes

Signature

function float llAtan2( float y, float x );