C++ (Cpp) _cairo_hull_eliminate_concave Beispiele

Beispiel #1

Datei: cairo-hull.c Projekt: mgya/xCairo

/* Given a set of vertices, compute the convex hull using the Graham
   scan algorithm. */
cairo_status_t
_cairo_hull_compute (cairo_pen_vertex_t *vertices, int *num_vertices)
{
    cairo_hull_t hull_stack[CAIRO_STACK_ARRAY_LENGTH (cairo_hull_t)];
    cairo_hull_t *hull;
    int num_hull = *num_vertices;

    if (CAIRO_INJECT_FAULT ())
	return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    if (num_hull > ARRAY_LENGTH (hull_stack)) {
	hull = _cairo_malloc_ab (num_hull, sizeof (cairo_hull_t));
    if (unlikely (hull == XNULL))
	    return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    } else {
	hull = hull_stack;
    }

    _cairo_hull_init (hull, vertices, num_hull);

    qsort (hull + 1, num_hull - 1,
	   sizeof (cairo_hull_t), _cairo_hull_vertex_compare);

    _cairo_hull_eliminate_concave (hull, num_hull);

    _cairo_hull_to_pen (hull, vertices, num_vertices);

    if (hull != hull_stack)
	xmemory_free (hull);

    return CAIRO_STATUS_SUCCESS;
}

Beispiel #2

Datei: cairo-hull.c Projekt: achellies/ISeeBrowser

/* Given a set of vertices, compute the convex hull using the Graham
   scan algorithm. */
cairo_status_t
_cairo_hull_compute (cairo_pen_vertex_t *vertices, int *num_vertices)
{
    cairo_hull_t *hull;
    int num_hull = *num_vertices;

    hull = _cairo_hull_create (vertices, num_hull);
    if (hull == NULL)
	return CAIRO_STATUS_NO_MEMORY;

    qsort (hull + 1, num_hull - 1,
	   sizeof (cairo_hull_t), _cairo_hull_vertex_compare);

    _cairo_hull_eliminate_concave (hull, num_hull);

    _cairo_hull_to_pen (hull, vertices, num_vertices);

    free (hull);

    return CAIRO_STATUS_SUCCESS;
}