1 files changed, 29 insertions, 0 deletions
diff --git a/src/mod360.cpp b/src/mod360.cpp
new file mode 100644
index 000000000..a30aa65a7
--- /dev/null
+++ b/src/mod360.cpp
@@ -0,0 +1,29 @@
+#include <glib.h>
+#include <math.h>
+
+/** Returns \a x wrapped around to between 0 and less than 360,
+    or 0 if \a x isn't finite.
+**/
+double mod360(double const x)
+{
+    double const m = fmod(x, 360.0);
+    double const ret = ( isnan(m)
+                         ? 0.0
+                         : ( m < 0
+                             ? m + 360
+                             : m ) );
+    g_return_val_if_fail(0.0 <= ret && ret < 360.0,
+                         0.0);
+    return ret;
+}
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :