Function: luglock

Syntax

luglock ({<num>})

Type

point

Returns

The 3-D coordinates of a lug point on a graphic primitive closest to the mouse position. The user may indicate a graphic primitive within any active graphic window.

The rules for how the system decides on a successful hit are as follows:

1) Only graphic primitives which are members of the window’s pick_group are examined. On window creation, a window’s pick_group is the all group.

2) Only graphic primitives which satisfy the selection criteria in a window’s pick_filter are examined. On window creation, a window’s pick_filter is undefined implying no filter.

3) Only graphic primitives whose lugs are currently shown are examined. A primitive’s lugs are shown if its entity.lugs attribute is set.

4) Only graphic primitives which are within the window’s pick_tolerance of the mouse position are examined. A window’s pick_tolerance is measured in pixels with a value of 10 on window creation.

Parameters

In addition to returning the coordinates of the "hit" lug point, the system epointer this is set to the primitive to enable further examination of the "hit entity", and the system numeric lug_index is set to the lug number, so that you know which lug was hit.

When a hit is successful, the system numeric found is set to one. On failure, found is set to zero, and this is set to null.

Confirmation of the selected point is given on the monitor. This message is of level six and can be suppressed by using a lower value of err_level,

err_level = 5

See Also

Commands:

uncursor

Functions:

plock(point)

Identifiers:

epick (epointer), err_level (numeric), found (numeric), lug_index (numeric), pick_cursor (cursor), this (epointer), tracking (procedure)

Structures:

entity.lugs, entity.lug_style, window.pick_filter, window.pick_group, window.pick_tolerance