Revert "Correctly handle G92 in hosts" as argued in #443

This reverts commit 1877d2cc.

Conflicts:
	printrun/gcoder.py

printrun/gcoder.py

@@ -96,8 +96,7 @@ class Layer(list):
         self.z = z
 
     def _preprocess(self, current_x, current_y, current_z,
-                    offset_x, offset_y, offset_z,
-                    ignore_noe = False, host_mode = True):
+                    offset_x, offset_y, offset_z, ignore_noe = False):
         xmin = float("inf")
         ymin = float("inf")
         zmin = 0
@@ -146,14 +145,9 @@ class Layer(list):
                     if line.z is not None: current_z = 0
 
             elif line.command == "G92":
-                if host_mode:
-                    current_x = line.x or current_x
-                    current_y = line.y or current_y
-                    current_z = line.z or current_z
-                else:
-                    if line.x is not None: offset_x = current_x - line.x
-                    if line.y is not None: offset_y = current_y - line.y
-                    if line.z is not None: offset_z = current_z - line.z
+                if line.x is not None: offset_x = current_x - line.x
+                if line.y is not None: offset_y = current_y - line.y
+                if line.z is not None: offset_z = current_z - line.z
 
             line.current_x = current_x
             line.current_y = current_y
@@ -190,14 +184,14 @@ class GCode(object):
 
     est_layer_height = None
 
-    def __init__(self, data, host_mode = True):
+    def __init__(self, data):
         self.lines = [Line(l2) for l2 in
                       (l.strip() for l in data)
                       if l2]
         self._preprocess_lines()
         self.filament_length = self._preprocess_extrusion()
         self._create_layers()
-        self._preprocess_layers(host_mode = host_mode)
+        self._preprocess_layers()
 
     def __len__(self):
         return len(self.line_idxs)
@@ -374,7 +368,7 @@ class GCode(object):
     def num_layers(self):
         return len(self.layers)
 
-    def _preprocess_layers(self, host_mode = True):
+    def _preprocess_layers(self):
         xmin = float("inf")
         ymin = float("inf")
         zmin = 0
@@ -394,7 +388,7 @@ class GCode(object):
         for l in self.all_layers:
             meta = l._preprocess(current_x, current_y, current_z,
                                  offset_x, offset_y, offset_z,
-                                 ignore_noe, host_mode)
+                                 ignore_noe)
             current_x, current_y, current_z = meta[0]
             offset_x, offset_y, offset_z = meta[1]
             (xm, xM), (ym, yM), (zm, zM) = meta[2:]