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[clinton/Smoothieware.git] / src / modules / robot / Robot.cpp

diff --git a/src/modules/robot/Robot.cpp b/src/modules/robot/Robot.cpp
index d63b4e5..c8e3215 100644 (file)
--- a/src/modules/robot/Robot.cpp
+++ b/src/modules/robot/Robot.cpp
@@ -98,7 +98,6 @@
 #define ymax_checksum                      CHECKSUM("y_max")
 #define zmax_checksum                      CHECKSUM("z_max")
 
-#define ARC_ANGULAR_TRAVEL_EPSILON 5E-9F // Float (radians)
 #define PI 3.14159265358979323846F // force to be float, do not use M_PI
 
 // The Robot converts GCodes into actual movements, and then adds them to the Planner, which passes them to the Conveyor so they can be added to the queue
@@ -1456,7 +1455,8 @@ bool Robot::append_arc(Gcode * gcode, const float target[], const float offset[]
         return false;
     }
 
-    // Scary math
+    // Scary math.
+    // We need to use arc_milestone here to get accurate arcs as previous machine_position may have been skipped due to small movements
     float center_axis0 = this->arc_milestone[this->plane_axis_0] + offset[this->plane_axis_0];
     float center_axis1 = this->arc_milestone[this->plane_axis_1] + offset[this->plane_axis_1];
     float linear_travel = target[this->plane_axis_2] - this->arc_milestone[this->plane_axis_2];