llGetAlpha

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Summary

Function: float llGetAlpha( integer face );

Returns a float that is the alpha of face.

• integer face face number or ALL_SIDES

If face is ALL_SIDES then the function returns the sum of alpha of all the faces on the prim, range [0, sides] Otherwise the return is in the range [0, 1].

Caveats

  • If face indicates a face that does not exist the return is 0.0
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Examples

<lsl>//Tells the owner the alpha on all sides default {

   state_entry()
   {
       integer i = 0;
       integer max = llGetNumberOfSides();
       while(i < max)
       {
           llSay(0,"Face "+(string)i+" alpha is " + (string)llGetAlpha(i));
           ++i;
       }
   }
}</lsl>

Useful Snippets

<lsl>float AveragePrimAlpha() {//Since this is so simple you may just want to inline it instead of including the function.

   return (llGetAlpha(ALL_SIDES) / llGetNumberOfSides());

}</lsl>

See Also

Functions

•  llSetAlpha Sets the prim's alpha
•  llGetColor Gets the prim's color
•  llSetColor Sets the prim's color
•  llSetLinkColor Sets link's color
•  llSetLinkAlpha Sets link's alpha
•  llGetNumberOfSides Gets the number of faces on the prim

Articles

•  Translucent Color

Deep Notes

Rounding

Alpha is stored in a 1 byte, meaning there are 256 values that are possible. Consequently the values returned by this function are all multiples of 1/255. When the alpha value is initially stored the float value is rounded to the nearest multiple, turning 0.5 into 128/255.

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Signature

function float llGetAlpha( integer face );