2009-11-14 Colin D Bennet <colin@gibibit.com>

Trigonometry support.

	* include/grub/trig.h: New file.
	* lib/trig.c: Likewise.
	* maintainance/gentrigtables.py: Likewise.
	* conf/common.rmk (pkglib_MODULES): Add trig.mod.
	(trig_mod_SOURCES): New variable.
	(trig_mod_CFLAGS): Likewise.
	(trig_mod_LDFLAGS): Likewise.

maintainance/gentrigtables.py

@@ -0,0 +1,58 @@
+#!/usr/bin/python
+# Script to generate trigonometric function tables.
+#
+#  GRUB  --  GRand Unified Bootloader
+#  Copyright (C) 2008  Free Software Foundation, Inc.
+#
+#  GRUB is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  GRUB 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 General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+
+from math import *
+from sys import stdout
+
+def write(x):
+    stdout.write(x)
+
+def writeTable(arr, name):
+    indent = ' ' * 4
+    write("short ")
+    write(name)
+    write("[] =\n{\n")
+    write(indent)
+    for i in range(len(arr)):
+        if i != 0:
+            write(",")
+            if i % 10 == 0:
+                write("\n")
+                write(indent)
+        write("%d" % arr[i])
+    write("\n};\n")
+
+def main():
+    sintab = []
+    costab = []
+    for i in range(256):
+        # Convert to an angle in 1/256 of a circle.
+        x = i * 2 * pi / 256
+        sintab.append(int(round(sin(x) * 16384)))
+        costab.append(int(round(cos(x) * 16384)))
+
+    write("#define TRIG_ANGLE_MAX 256\n")
+    write("#define TRIG_FRACTION_SCALE 16384\n")
+    writeTable(sintab, "sintab")
+    writeTable(costab, "costab")
+
+if __name__ == "__main__":
+    main()
+
+# vim:ai et sw=4 ts=4