message: RenderRectFilledRangeH() can't use cheap acosf() approximation for now.
diff: @@ -2352,7 +2352,8 @@ static inline float ImAcos01(float x)
  {
  if (x <= 0.0f) return IM_PI * 0.5f;
  if (x >= 1.0f) return 0.0f;
  - return (-0.69813170079773212f * x * x - 0.87266462599716477f) * x + 1.5707963267948966f; // Cheap approximation, enough for what we do.
  + return acosf(x);
  + //return (-0.69813170079773212f * x * x - 0.87266462599716477f) * x + 1.5707963267948966f; // Cheap approximation, may be enough for what we do.
  }
  // FIXME: Cleanup and move code to ImDrawList.
  