adds functions gst_cast_float and gst_cast_double. Will use lrint and lrintf if available and a pure c rounding macro...

Original commit message from CVS:
adds functions gst_cast_float and gst_cast_double. Will use lrint and lrintf if available and a pure c rounding macro if not.

This is where optimised asm alternatives can be placed - omega, this means you!

However you have to prove that your asm version is faster than lrintf ;)

1 files changed, 54 insertions, 0 deletions

diff --git a/gst-libs/gst/floatcast/floatcast.h b/gst-libs/gst/floatcast/floatcast.h
new file mode 100644
index 00000000..3a232b76
--- /dev/null
+++ b/gst-libs/gst/floatcast/floatcast.h
@@ -0,0 +1,54 @@
+/* GStreamer
+ * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
+ * Library       <2002> Steve Baker <stevebaker_org@yahoo.co.uk>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __FLOATCAST_H__
+#define __FLOATCAST_H__
+
+#include <config.h>
+
+#if (HAVE_LRINT && HAVE_LRINTF)
+
+	/*	These defines enable functionality introduced with the 1999 ISO C
+	**	standard. They must be defined before the inclusion of math.h to
+	**	engage them. If optimisation is enabled, these functions will be 
+	**	inlined. With optimisation switched off, you have to link in the
+	**	maths library using -lm.
+	*/
+
+	#define	_ISOC9X_SOURCE	1
+	#define _ISOC99_SOURCE	1
+
+	#define	__USE_ISOC9X	1
+	#define	__USE_ISOC99	1
+
+	#include	<math.h>
+
+	#define gst_cast_float(x)	((gint)lrintf(x))
+	#define gst_cast_double(x)	((gint)lrint(x))
+	
+#else
+	/* use a standard c cast, but do rounding correctly */
+	#define gst_cast_float(x)	((x)>=0?(gint)((x)+0.5):(gint)((x)-0.5))
+	#define gst_cast_double(x)	((x)>=0?(gint)((x)+0.5):(gint)((x)-0.5))
+
+#endif
+
+#endif /* __FLOATCAST_H__ */
+