From 0c66c8b407574b4e8820cc01318cf2f7b6f1e139 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miloslav=20=C4=8C=C3=AD=C5=BE?= <tastyfish@seznam.cz>
Date: Sun, 6 Oct 2019 21:29:41 +0200
Subject: [PATCH] Improve point mapping

---
 raycastlib.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/raycastlib.h b/raycastlib.h
index 90651a7..f04017c 100644
--- a/raycastlib.h
+++ b/raycastlib.h
@@ -1649,9 +1649,10 @@ RCL_PixelInfo RCL_mapToScreen(RCL_Vector2D worldPosition, RCL_Unit height,
   cameraDir.x = cameraDir.y;
   cameraDir.y = -1 * tmp;
 
-  // decide whether the point is in the left or right part of screen
+  /* decide whether the point is in the left or right part of screen, using
+     dot product (non-normalized, as we only need to compare to 0) */
 
-  if (RCL_vectorsAngleCos(toPoint,cameraDir) <= 0)
+  if ((toPoint.x * cameraDir.x + toPoint.y * cameraDir.y) <= 0)
     a *= -1;
 
   result.position.x =