fixed cos sin

Helpers/fixedgen.py

@@ -0,0 +1,19 @@
+#!/usr/bin/env python3
+# Generator for sin/cos fixed point LUT tables.
+import math
+
+def generate_pi():
+    print(f"#define COM_FIXED_PI (com_fixed_t){int(math.pi * (1 << 16))}\n")
+    print(f"#define COM_FIXED_PI2 (com_fixed_t){int(math.pi*2 * (1 << 16))}\n")
+    print(f"#define COM_FIXED_PIHALF (com_fixed_t){int(math.pi/2 * (1 << 16))}\n")
+
+# Idea is to generate only one quadrant, as the values repeat later with different sign and order.
+def generate_sin_table(n_entries=128):
+    r = []
+    for n in range(n_entries):
+        r += [math.sin(math.pi*n/(n_entries*2))]
+    # r[n_entries-1]=1 # Make it converge to unit precisely
+    print(f"static const uint16_t com_fixed_sin_lut[{n_entries}] =", "{", ",\n".join((str(int(a * (1 << 16))) for a in r)), "};\n")
+
+generate_pi()
+generate_sin_table()