LSL Wiki : llGetBoundingBox

list llGetBoundingBox(key object)

Returns the bounding box around the object or avatar with the key object (including any linked prims) relative to the root prim, in a list: [ (vector) min_corner, (vector) max_corner ]

Note: when an avatar sits on an object, it becomes linked to it--and the avatar's bounding box then includes the object it is sitting on.

If the object defined by object does not exist, the list returned will contain no items.

Example:

// Ezhar's bounding box visualizer

default {
    state_entry() {
        llListen(3, "", llGetOwner(), ""); // listen for a target
    }
    
    listen(integer channel, string name, key id, string message) {
        llSensor(message, NULL_KEY, AGENT | ACTIVE | PASSIVE, 10, PI); // find the target
    }
    
    sensor(integer num_detected) {
        list bb;
        
        vector    min;
        vector    max;
        
        vector    offset;
        
        bb = llGetBoundingBox(llDetectedKey(0)); // get the bounding box
        min = llList2Vector(bb, 0); // min corner
        max = llList2Vector(bb, 1); // max corner
        
        offset = (min + max) / 2; // calculate the offset from the targets root prim center
        offset *= llDetectedRot(0); // rotate it by the targets rotation
        
        llSetText((string)min + "\n" + (string)max, <1, 1, 1>, 1.0); // display the bounding box corners as text
        
        llSetScale(-min + max); // change to the size of the bounding box
        llSetPos(llDetectedPos(0) + offset); // move to the target
        llSetRot(llDetectedRot(0)); // and match the targets rotation
    }
}

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Functions | Bounding Box | Center | Prim | Object