Issue 4961/2: Add offset_directed (Real)

[lilypond.git] / flower / include / offset.hh

diff --git a/flower/include/offset.hh b/flower/include/offset.hh
index cddec1fc00c7cb9acd4c85c7e52c572a3d1dc68c..c6c166cc428037cb1883363a5601a90d2ff68785 100644 (file)
--- a/flower/include/offset.hh
+++ b/flower/include/offset.hh
@@ -126,6 +126,7 @@ IMPLEMENT_ARITHMETIC_OPERATOR (Offset, *);
 Offset complex_multiply (Offset, Offset);
 Offset complex_divide (Offset, Offset);
 Offset complex_exp (Offset);
+Offset offset_directed (Real);
 
 inline Offset
 Offset::operator *= (Offset z2)
@@ -169,5 +170,13 @@ dot_product (Offset o1, Offset o2)
   return o1[X_AXIS] * o2[X_AXIS] + o1[Y_AXIS] * o2[Y_AXIS];
 }
 
+inline
+Real
+cross_product (Offset o1, Offset o2)
+{
+  return o1[X_AXIS] * o2[Y_AXIS] - o1[Y_AXIS] * o2[X_AXIS];
+}
+
+
 #endif /* OFFSET_HH */