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Second Life Creation

llDetectedGrab

vector llDetectedGrab(integer Number)

Returns the grab offset of a user touching the object.

Returns <0.0, 0.0, 0.0> if Number is not a valid object.

Parameters
Number (integer)
Technical Details
  • Return Type: vector
  • Energy: 10

Basic Grab Detection

Section titled “Basic Grab Detection”
default
{
    state_entry()
    {
        llSetStatus(PRIM_PHYSICS, TRUE); // This allows the object to be "grabbed" and dragged
    }
    touch(integer num_detected)
    {
        llSay(0, (string)llDetectedGrab(0)); // Be prepared for a great amount of chatted info.
                                              // The faster you move the mouse while grabbing the object the greater the offset becomes.
                                              // This is not due to the speed but the reaction time of the turn around of the physical prim,
                                              // thus an offset (distance from grab to prim center) is created and measured by this function.
    }
}

Following Mouse Grabs

Section titled “Following Mouse Grabs”

This example creates a cone-shaped object that follows the mouse when grabbed:

/*
Simple llDetectedGrab illustration, rez a prim and add this script.
The prim will become a cone that follows mouse grabs.


Click and hold the mouse button down on the object, then:
- Drag left and right to move parallel to the camera focal plane.
- Drag up and down to move to and from the camera.
- Hold down Ctrl, then drag up and down to move vertically.
*/


default
{
    state_entry()
    {
        llMinEventDelay(0.25);
        llSetStatus(STATUS_PHYSICS, FALSE); // make the object static for simplicity
        llSetPrimitiveParams([
            PRIM_SIZE, <0.5, 0.5, 0.5>,
            PRIM_TYPE, PRIM_TYPE_CYLINDER, PRIM_HOLE_DEFAULT, <0.0, 1.0, 0.0>,
              0.0, ZERO_VECTOR, ZERO_VECTOR, ZERO_VECTOR
        ]); // a cone that can follow the mouse pointer
    }


    touch(integer total_number)
    {
        llLookAt(llGetPos() + llDetectedGrab(0), 1.0, 1.0);
    }
}

Caveats

Section titled “Caveats”
  • When called in HUD attachments, values returned are affected by the wearer’s position and rotation.
  • For physical objects, grabs are detected only if the avatar has permission to move the object and the object is not locked.
  • For non-physical objects, grabs from all avatars are detected.
  • llDetectedGrab() is not blocked by STATUS_BLOCK_GRAB or STATUS_BLOCK_GRAB_OBJECT.

Notes

Section titled “Notes”
  • The grab offset represents the distance between where the avatar grabs the object and its center.
  • The offset changes based on how quickly the avatar moves the mouse while grabbing, which affects the physical reaction time of the prim.
  • This function only works in the touch event.
  • Returns <0.0, 0.0, 0.0> if the number parameter is out of range or called from an event other than the touch event.

See Also

Section titled “See Also”