+ target.align_to ((Axis)scm_to_int (axis),
+ scm_to_double (dir));
+ return target.smobbed_copy ();
+}
+
+LY_DEFINE (ly_stencil_fonts, "ly:stencil-fonts",
+ 1, 0, 0, (SCM s),
+ "Analyze @var{s}, and return a list of fonts used"
+ " in@tie{}@var{s}.")
+{
+ LY_ASSERT_SMOB (Stencil, s, 1);
+ Stencil *stil = unsmob_stencil (s);
+ return find_expression_fonts (stil->expr ());
+}
+
+LY_DEFINE (ly_stencil_in_color, "ly:stencil-in-color",
+ 4, 0, 0, (SCM stc, SCM r, SCM g, SCM b),
+ "Put @var{stc} in a different color.")
+{
+ LY_ASSERT_SMOB (Stencil, stc, 1);
+ Stencil *stil = unsmob_stencil (stc);
+ return Stencil (stil->extent_box (),
+ scm_list_3 (ly_symbol2scm ("color"),
+ scm_list_3 (r, g, b),
+ stil->expr ())).smobbed_copy ();
+}
+
+struct Stencil_interpret_arguments
+{
+ SCM func;
+ SCM arg1;
+};
+
+void stencil_interpret_in_scm (void *p, SCM expr)
+{
+ Stencil_interpret_arguments *ap = (Stencil_interpret_arguments *) p;
+ scm_call_2 (ap->func, ap->arg1, expr);
+}
+
+LY_DEFINE (ly_interpret_stencil_expression, "ly:interpret-stencil-expression",
+ 4, 0, 0, (SCM expr, SCM func, SCM arg1, SCM offset),
+ "Parse @var{expr}, feed bits to @var{func} with first arg"
+ " @var{arg1} having offset @var{offset}.")
+{
+ LY_ASSERT_TYPE (ly_is_procedure, func, 2);
+
+ Stencil_interpret_arguments a;
+ a.func = func;
+ a.arg1 = arg1;
+ Offset o = ly_scm2offset (offset);
+
+ interpret_stencil_expression (expr, stencil_interpret_in_scm, (void *) & a, o);
+
+ return SCM_UNSPECIFIED;
+}
+
+LY_DEFINE (ly_bracket, "ly:bracket",
+ 4, 0, 0,
+ (SCM a, SCM iv, SCM t, SCM p),
+ "Make a bracket in direction@tie{}@var{a}. The extent of the"
+ " bracket is given by @var{iv}. The wings protrude by an amount"
+ " of@tie{}@var{p}, which may be negative. The thickness is given"
+ " by@tie{}@var{t}.")
+{
+ LY_ASSERT_TYPE (is_axis, a, 1);
+ LY_ASSERT_TYPE (is_number_pair, iv, 2);
+ LY_ASSERT_TYPE (scm_is_number, t, 3);
+ LY_ASSERT_TYPE (scm_is_number, p, 4);
+
+ return Lookup::bracket ((Axis)scm_to_int (a), ly_scm2interval (iv),
+ scm_to_double (t),
+ scm_to_double (p),
+ 0.95 * scm_to_double (t)).smobbed_copy ();
+}
+
+LY_DEFINE (ly_stencil_rotate, "ly:stencil-rotate",
+ 4, 0, 0, (SCM stil, SCM angle, SCM x, SCM y),
+ "Return a stencil @var{stil} rotated @var{angle} degrees around"
+ " the relative offset (@var{x}, @var{y}). E.g. an offset of"
+ " (-1, 1) will rotate the stencil around the left upper corner.")
+{
+ Stencil *s = unsmob_stencil (stil);
+ LY_ASSERT_SMOB (Stencil, stil, 1);
+ LY_ASSERT_TYPE (scm_is_number, angle, 2);
+ LY_ASSERT_TYPE (scm_is_number, x, 3);
+ LY_ASSERT_TYPE (scm_is_number, y, 4);
+ Real a = scm_to_double (angle);
+ Real x_off = scm_to_double (x);
+ Real y_off = scm_to_double (y);
+
+ SCM new_s = s->smobbed_copy ();
+ Stencil *q = unsmob_stencil (new_s);
+ q->rotate_degrees (a, Offset (x_off, y_off));
+ return new_s;
+}
+
+LY_DEFINE (ly_stencil_rotate_absolute, "ly:stencil-rotate-absolute",
+ 4, 0, 0, (SCM stil, SCM angle, SCM x, SCM y),
+ "Return a stencil @var{stil} rotated @var{angle} degrees around"
+ " point (@var{x}, @var{y}), given in absolute coordinates.")
+{
+ Stencil *s = unsmob_stencil (stil);
+ LY_ASSERT_SMOB (Stencil, stil, 1);
+ LY_ASSERT_TYPE (scm_is_number, angle, 2);
+ LY_ASSERT_TYPE (scm_is_number, x, 3);
+ LY_ASSERT_TYPE (scm_is_number, y, 4);
+ Real a = scm_to_double (angle);
+ Real x_off = scm_to_double (x);
+ Real y_off = scm_to_double (y);
+
+ SCM new_s = s->smobbed_copy ();
+ Stencil *q = unsmob_stencil (new_s);
+ q->rotate_degrees_absolute (a, Offset (x_off, y_off));
+ return new_s;
+}
+
+LY_DEFINE (ly_round_filled_box, "ly:round-filled-box",
+ 3, 0, 0,
+ (SCM xext, SCM yext, SCM blot),
+ "Make a @code{Stencil} object that prints a black box of"
+ " dimensions @var{xext}, @var{yext} and roundness @var{blot}.")
+{
+ LY_ASSERT_TYPE (is_number_pair, xext, 1);
+ LY_ASSERT_TYPE (is_number_pair, yext, 2);
+ LY_ASSERT_TYPE (scm_is_number, blot, 3);
+
+ return Lookup::round_filled_box (Box (ly_scm2interval (xext), ly_scm2interval (yext)),
+ scm_to_double (blot)).smobbed_copy ();
+}
+
+LY_DEFINE (ly_round_filled_polygon, "ly:round-filled-polygon",
+ 2, 0, 0,
+ (SCM points, SCM blot),
+ "Make a @code{Stencil} object that prints a black polygon with"
+ " corners at the points defined by @var{points} (list of coordinate"
+ " pairs) and roundness @var{blot}.")
+{
+ SCM_ASSERT_TYPE (scm_ilength (points) > 0, points, SCM_ARG1, __FUNCTION__, "list of coordinate pairs");
+ LY_ASSERT_TYPE (scm_is_number, blot, 2);
+ vector<Offset> pts;
+ for (SCM p = points; scm_is_pair (p); p = scm_cdr (p))
+ {
+ SCM scm_pt = scm_car (p);
+ if (scm_is_pair (scm_pt)) {
+ pts.push_back (ly_scm2offset (scm_pt));
+ } else {
+ // TODO: Print out warning
+ }
+ }
+ return Lookup::round_filled_polygon (pts, scm_to_double (blot)).smobbed_copy ();
+}
+
+LY_DEFINE (ly_register_stencil_expression, "ly:register-stencil-expression",
+ 1, 0, 0,
+ (SCM symbol),
+ "Add @var{symbol} as head of a stencil expression.")
+{
+ LY_ASSERT_TYPE (ly_is_symbol, symbol, 1);
+ register_stencil_head (symbol);
+ return SCM_UNSPECIFIED;
+}
+
+LY_DEFINE (ly_all_stencil_expressions, "ly:all-stencil-expressions",
+ 0, 0, 0,
+ (),
+ "Return all symbols recognized as stencil expressions.")
+{
+ return all_stencil_heads ();