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// Gets sin of specified radians.
// Input and output format is fixed point sign.19.12
int32 f32sin(int32 radians)
{
  const int32 PI2_PRECISION_BITS = 20;
  const int32 PI2_RECIPROCAL     = (1.0f / (2*M_PI)) * (1<<PI2_PRECISION_BITS);
 
  // Divide incoming radians by 2*PI, so it is a "normalized"
  // angle between -1 and +1, where 1 equals 2*PI (360 degree).
  int32 value = (radians * PI2_RECIPROCAL) >> PI2_PRECISION_BITS;
 
  // Now that we have our normalized angle,
  // we just discard all numbers which are not in the range -1..+1.
  // Since this is fixed point, a simple AND operation can be used.
  value &= floattof32(1)-1;
 
  // Always wrap normalized angle to -0.5(-PI)..+0.5(+PI)
  if(value > floattof32(0.5f))
    value -= floattof32(1); // subtract 2*PI in normalized form
  else
    if(value < floattof32(-0.5f))
      value += floattof32(1); // add 2*PI in normalized form
 
  // Convert normalized angle (-1..1) back to radians (-2*PI..2*PI)
  value = f32mul(value, floattof32(2*M_PI));
 
  // Approximate sin value
  const int32 B = floattof32(1.2732395447351f);
  const int32 C = floattof32(-0.405284734569f);
  return f32mul(B, value) + f32mul(f32mul(C, value), f32abs(value));
}