From 8aeb11f77106b4aae734120915c17c6d1a59b035 Mon Sep 17 00:00:00 2001
From: Oleg Kalachev <okalachev@gmail.com>
Date: Wed, 12 Sep 2018 23:35:53 +0300
Subject: [PATCH] snippet: correct formula for calculating angle to horizon

---
 docs/snippets.md | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/docs/snippets.md b/docs/snippets.md
index 3d221f81..bfeb8e2f 100644
--- a/docs/snippets.md
+++ b/docs/snippets.md
@@ -86,12 +86,14 @@ flipped = not -pi_2 <= telem.pitch <= pi_2 or not -pi_2 <= telem.roll <= pi_2
 
 Рассчет общего угла коптера к горизонту:
 
-TODO: fix
-
 ```python
+pi_2 = math.pi / 2
 telem = get_telemetry()
 
+flipped = not -pi_2 <= telem.pitch <= pi_2 or not -pi_2 <= telem.roll <= pi_2
 angle_to_horizon = math.atan(math.hypot(math.tan(telem.pitch), math.tan(telem.roll)))
+if flipped:
+    angle_to_horizon = math.pi - angle_to_horizon
 ```
 
 ---