llDetectedTouchUV

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Summary

Function: vector llDetectedTouchUV( integer index );
0.0 Forced Delay
10.0 Energy

Returns a vector that is the texture coordinates for where the prim was touched. The x & y vector positions contain the horizontal (u) & vertical (v) texture coordinates respectively (<u, v, 0.0>). Like llDetectedTouchST, the interval of each component will be [0.0, 1.0] unless the texture repeats are set to a non-default value. Increasing or decreasing the texture repeats of the face will change this interval accordingly. Additionally, unlike with llDetectedTouchST, changing a texture's rotation will change the results of this function.

TOUCH_INVALID_TEXCOORD is returned when the touch UV coordinates cannot be determined. See Caveats for further details.

• integer index – Index of detection information

index does not support negative indexes. 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.

Caveats

  • If index is out of bounds the script continues to execute without an error message.
  • TOUCH_INVALID_TEXCOORD is returned when...
    • The avatar's viewer does not support face touch detection.
    • The touch has moved off the surface of the prim.
    • The touch happened too close to the edge of the face to determine a location.
    • The event triggered is not a touch event.

Examples

default
{
    touch_start(integer total_number)
    {
        integer face = llDetectedTouchFace(0);
        vector  touchUV   = llDetectedTouchUV(0);

//      ZERO_VECTOR (<0.0, 0.0, 0.0> ... the origin) is in the bottom left corner of the texture
//      touchUV.x goes across the texture from left to right
//      touchUV.y goes up the texture from bottom to top

        if (face == TOUCH_INVALID_FACE)
            llWhisper(PUBLIC_CHANNEL, "Sorry, your viewer doesn't support touched faces.");
        else if (touchUV == TOUCH_INVALID_TEXCOORD)
            llWhisper(PUBLIC_CHANNEL, "Sorry, the touch position upon the texture could not be determined.");
        else
            llSay(PUBLIC_CHANNEL, "llDetectedTouchUV(" + (string)touchUV + ")"
                    + "\ntouchUV.x = " + (string)touchUV.x
                    + "\ntouchUV.y = " + (string)touchUV.y);
    }
}

integer numberOfRows    = 12;
integer numberOfColumns = 12;

default
{
    touch_start(integer num_detected)
    {
        vector touchUV = llDetectedTouchUV(0);

//      ZERO_VECTOR (<0.0, 0.0, 0.0> ... the origin) is in the bottom left corner of the texture
//      touchUV.x goes across the texture from left to right
//      touchUV.y goes up the texture from bottom to top

        integer columnIndex = (integer) (touchUV.x * numberOfColumns);
        integer rowIndex    = (integer) (touchUV.y * numberOfRows);
        integer cellIndex   = rowIndex * numberOfColumns + columnIndex;

        llSay(PUBLIC_CHANNEL, "UV grid (" + (string)columnIndex + ", " + (string)rowIndex + ") --> cell " + (string)cellIndex);
    }
}

See Also

Deep Notes

History

Footnotes

  1. ^ The ranges in this article are written in Interval Notation.

Signature

function vector llDetectedTouchUV( integer index );

Haiku

Early aurora
A single face gently touched
in front of a cube

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