llGetClosestNavPoint

Category: Pathfinding

function

Function syntax

list llGetClosestNavPoint(

vector point,// Position vector in region-local coordinates.
list options// A list of GCNP_* flags and parameters to configure the search limits.

);

Returns: list
Energy: 10

Used to get a point on the navmesh that is the closest point to point.

If an option is not explicitly set, the default value for that option is used.

Returns a list containing a single vector which is the closest point on the navmesh to the point provided or an empty list.

list result = llGetClosestNavPoint(ZERO_VECTOR, []);

Specification

From the LSL definitions: GetClosestNavPointParam (rule, then its arguments)

CHARACTER_TYPE  // Specifies the preferred surface and terrain terrain-type for the character (default is CHARACTER_TYPE_NONE).GCNP_RADIUS  // Used with llGetClosestNavPoint to limit how far out to search for a navigation point.GCNP_STATIC  // Used with llGetClosestNavPoint to specify that the test should use the static navmesh, ignoring all dynamic obstacles.

Constant	Type	Value	Description
`GCNP_RADIUS`	integer	`0`	Limits how far out to search for a navigation point.
`GCNP_STATIC`	integer	`1`	Specifies whether the test should use the static or dynamic nav mesh. In the static case, all dynamic obstacles are ignored.
`CHARACTER_TYPE`	integer	`6`	Filters nav points by eliminating nav mesh faces which are 0% walkable for the specified character type. In the default CHARACTER_TYPE_NONE case, all nav mesh faces are included.

Options	V	Parameters
[ float `distance` ]	[ `20.0` ]	Limits how far out to search for a navigation point.
[ integer `use_static_mesh` ]	[ `FALSE` ]	Specifies whether the test should use the static or dynamic nav mesh. In the static case, all dynamic obstacles are ignored.
[ integer `type` ]	[ `CHARACTER_TYPE_NONE` ]	Filters nav points by eliminating nav mesh faces which are 0% walkable for the specified character type. In the default `CHARACTER_TYPE_NONE` case, all nav mesh faces are included.

Caveats

There is no guarantee that a path exists from your current location to the returned point.

Examples

Example 1

23 collapsed lines
create_character()
{
//  Clear any previous character behaviors
    llDeleteCharacter();

//  default speed is 20
    llCreateCharacter([CHARACTER_DESIRED_SPEED, 10.0]);
    llWanderWithin(llGetPos(), <64.0, 64.0, 2.0>, []);
}

default
{
    on_rez(integer start_param)
    {
        llResetScript();
    }

    state_entry()
    {
        create_character();
    }

    touch_start(integer num_detected)
    {
        vector currentPos = llGetPos();
        list points = llGetClosestNavPoint(currentPos, [GCNP_RADIUS, 10.0] );

        if (!llGetListLength(points))
6 collapsed lines
            return;

        llSay(0, "current position " + (string)currentPos
            + " and closest nav point " + (string)llList2Vector(points, 0) );
    }
}

Notes

Using the method incurs a one frame script sleep and the call can be extremely expensive. It is intended to be used in response to a path_update message indicating an inability to reach a requested destination (e.g., because the character or the destination is off the mesh).

History

Date of Release 31/07/2012