LlDetectedTouchFace

Function notes

For the touch category of events only. The prim that was touched may not be the prim receiving the event, use llDetectedLinkNumber to check for this; likewise you can use llDetectedTouchFace to determine which face was touched.

Return value notes

Returns an integer that is the index of the face the avatar clicked on.

Caveats

TOUCH_INVALID_FACE is returned when...
- The avatar's viewer does not support face touch detection.
- The touch has moved off the surface of the prim.
- The event triggered is not a touch event.

Examples

// This is the essential script to drop in a prim when you need to ascertain the number of a face (or faces)
// Touch the prim surfaces to learn their face numbers, which you can then use in other scripts for texturing, colouring etc.

say(string message)
{
    llSay(PUBLIC_CHANNEL, message);
}

default
{
    touch_start(integer num_detected)
    {
        integer face = llDetectedTouchFace(0);

        if (face == TOUCH_INVALID_FACE)
//      {
            say("The touched face could not be determined");
//      }
        else
//      {
            say("You touched face number " + (string) face);
//      }
    }
}

default
{
    touch_start(integer num_detected)
    {
        integer link = llDetectedLinkNumber(0);
        integer face = llDetectedTouchFace(0);

        if (face == TOUCH_INVALID_FACE)
            llSay(PUBLIC_CHANNEL, "Sorry, your viewer doesn't support touched faces.");
        else
        {
            // store the original color
            list   colorParams   = llGetLinkPrimitiveParams(link, [PRIM_COLOR, face]);
            vector originalColor = llList2Vector(colorParams, 0);

            // color detected face white
            llSetLinkColor(link, <1.0, 1.0, 1.0>, face);
            llSleep(0.2);

            // color detected face black
            llSetLinkColor(link, ZERO_VECTOR, face);
            llSleep(0.2);

            // color detected face back to original color
            llSetLinkColor(link, originalColor, face);
        }
    }
}

History

Introduced in Viewer SVN:870 r92872 Branch:Release Wednesday, 23 July 2008.
Server support available in Second Life Server 1.24.7.98039, client support in Release Candidate viewer 1.21.4 (98167)
Date of Release Server 29-08-2008
Date of Release Client 16-10-2008

Shared wiki helpers

The original page also injects shared parameter notes, caveats or issue information through these helpers. Their conditional MediaWiki logic is not reproduced here; inspect the preserved helper source for additional material.

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Original shared helper source (conditional wiki logic is not evaluated)

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