From 12d72363cb58d3afed33bb33d690c6aa6c4bc015 Mon Sep 17 00:00:00 2001
From: Scott Lahteine <sourcetree@thinkyhead.com>
Date: Fri, 19 Aug 2016 05:05:48 -0500
Subject: [PATCH] Do Delta radius check without sqrt

---
 Marlin/Marlin_main.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index 0c64defb2..3fa9725d5 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -3667,8 +3667,7 @@ inline void gcode_G28() {
 
           #if ENABLED(DELTA)
             // Avoid probing outside the round or hexagonal area of a delta printer
-            float distance_from_center = HYPOT(xProbe, yProbe);
-            if (distance_from_center > DELTA_PROBEABLE_RADIUS) continue;
+            if (sq(xProbe) + sq(yProbe) > sq(DELTA_PROBEABLE_RADIUS)) continue;
           #endif
 
           float measured_z = probe_pt(xProbe, yProbe, stow_probe_after_each, verbose_level);