}
LY_DEFINE (ly_make_stencil, "ly:make-stencil",
- 3, 0, 0, (SCM expr, SCM xext, SCM yext),
+ 1, 2, 0, (SCM expr, SCM xext, SCM yext),
" \n"
"Stencils are a device independent output expressions."
"They carry two pieces of information: \n\n"
"1: a specification of how to print this object. "
"This specification is processed by the output backends, "
" for example @file{scm/output-ps.scm}.\n\n"
- "2: the vertical and horizontal extents of the object.\n\n")
+ "2: the vertical and horizontal extents of the object.\n\n"
+ "If the extents are unspecified, they are taken to be empty."
+ )
{
SCM_ASSERT_TYPE (!scm_is_pair (expr)
|| is_stencil_head (scm_car (expr)),
expr, SCM_ARG1, __FUNCTION__, "registered stencil expression");
- SCM_ASSERT_TYPE (is_number_pair (xext), xext, SCM_ARG2, __FUNCTION__, "number pair");
- SCM_ASSERT_TYPE (is_number_pair (yext), yext, SCM_ARG3, __FUNCTION__, "number pair");
- Box b (ly_scm2interval (xext), ly_scm2interval (yext));
+ Interval x;
+ if (xext != SCM_UNDEFINED)
+ {
+ SCM_ASSERT_TYPE (is_number_pair (xext), xext, SCM_ARG2, __FUNCTION__, "number pair");
+ x = ly_scm2interval (xext);
+ }
+
+ Interval y;
+ if (yext != SCM_UNDEFINED)
+ {
+ SCM_ASSERT_TYPE (is_number_pair (yext), yext, SCM_ARG3, __FUNCTION__, "number pair");
+ y = ly_scm2interval (yext);
+ }
+
+ Box b (x, y);
Stencil s (b, expr);
return s.smobbed_copy ();
}