Allow going back a line while hand-picking points

hexrd/ui/calibration/calibration_runner.py

@@ -1,5 +1,6 @@
 import copy
 from functools import partial
+import itertools
 from pathlib import Path
 
 import h5py
@@ -185,6 +186,7 @@ def hand_pick_points(self):
         picker.point_picked.connect(self.point_picked)
         picker.line_completed.connect(self.line_completed)
         picker.last_point_removed.connect(self.last_point_removed)
+        picker.last_line_restored.connect(self.last_line_restored)
         picker.finished.connect(self.calibration_line_picker_finished)
         picker.view_picks.connect(self.on_view_picks_clicked)
         picker.accepted.connect(self.finish_line)
@@ -626,8 +628,8 @@ def point_picked(self, x, y):
             self.current_data_list[ind] = data
             self.increment_overlay_data_index()
 
-            # In case a point was over-written, force an update of
-            # the line artists.
+            # The line builder doesn't accurately update the lines
+            # during Laue picking, so we force it here.
             self.update_lines_from_picks()
 
     def line_completed(self):
@@ -642,13 +644,26 @@ def last_point_removed(self):
                 # Still nothing to do
                 return
             # Remove the last point of data
-            self.current_data_list.pop(-1)
+            self.current_data_list.pop()
         elif self.active_overlay.is_laue:
             self.decrement_overlay_data_index()
             _, _, ind = self.current_data_path
             if 0 <= ind < len(self.current_data_list):
                 self.current_data_list[ind] = (np.nan, np.nan)
 
+            # The line builder doesn't accurately update the lines
+            # during Laue picking, so we force it here.
+            self.update_lines_from_picks()
+
+    def last_line_restored(self):
+        # This should only be called for powder overlays, because
+        # Laue overlays are single-line
+        while self.current_data_list:
+            self.current_data_list.pop()
+
+        # Go back one line
+        self.decrement_overlay_data_index()
+
     def disable_line_picker(self, b=True):
         if self.line_picker:
             self.line_picker.disabled = b
@@ -686,23 +701,29 @@ def update_lines_from_picks(self):
         if not self.line_picker:
             return
 
-        # Save the previous index
-        prev_data_index = self.overlay_data_index
-
         picker = self.line_picker
-        for i, line in enumerate(picker.lines):
-            self.overlay_data_index = i
-            if not self.current_data_path:
-                break
+        if self.active_overlay.is_powder:
+            # Save the previous index
+            prev_data_index = self.overlay_data_index
+            for i, line in enumerate(picker.lines):
+                self.overlay_data_index = i
+                if not self.current_data_path:
+                    break
 
-            if self.current_data_list:
-                data = list(zip(*self.current_data_list))
-            else:
-                data = [(), ()]
+                if self.current_data_list:
+                    data = list(zip(*self.current_data_list))
+                else:
+                    data = [(), ()]
 
-            line.set_data(data)
+                line.set_data(data)
+
+            self.overlay_data_index = prev_data_index
+        else:
+            # For Laue, there should be just one line that contains
+            # all of the points.
+            data = list(zip(*itertools.chain(*self.overlay_picks.values())))
+            picker.lines[0].set_data(data)
 
-        self.overlay_data_index = prev_data_index
         picker.canvas.draw_idle()
 
     def auto_pick_points(self):

hexrd/ui/calibration/structureless/runner.py

@@ -601,7 +601,7 @@ def polar_lines_to_cart(data, instr):
         calibrator_line = {}
         panel_found = np.zeros(line.shape[0], dtype=bool)
         for det_key, panel in instr.detectors.items():
-            points = angles_to_cart(line, panel)
+            points = angles_to_cart(line, panel, tvec_c=instr.tvec)
             _, on_panel = panel.clip_to_panel(points)
             points[~on_panel] = np.nan
             valid_points = ~np.any(np.isnan(points), axis=1)

hexrd/ui/line_picker_dialog.py

@@ -32,6 +32,9 @@ class LinePickerDialog(QObject):
     # Emitted when the last point was removed
     last_point_removed = Signal()
 
+    # Emitted when the last line was restored
+    last_line_restored = Signal()
+
     # Emitted when "Picks Table" was clicked
     view_picks = Signal()
 
@@ -57,7 +60,9 @@ def __init__(self, canvas, parent, single_line_mode=False,
         self.ui.setWindowFlags(flags | Qt.Tool)
 
         self.linebuilder = None
+        self.previous_linebuilders = []
         self.lines = []
+        self.unused_colors = []
 
         self.two_click_mode = self.ui.two_click_mode.isChecked()
 
@@ -105,7 +110,10 @@ def update_enable_states(self):
         linebuilder = self.linebuilder
         enable_back_button = (
             linebuilder is not None and
-            all(z for z in [linebuilder.xs, linebuilder.ys])
+            (
+                all(z for z in [linebuilder.xs, linebuilder.ys]) or
+                bool(self.previous_linebuilders)
+            )
         )
         self.ui.back_button.setEnabled(enable_back_button)
 
@@ -134,6 +142,7 @@ def clear(self):
             self.lines.pop(0).remove()
 
         self.linebuilder = None
+        self.previous_linebuilders.clear()
 
         self.zoom_canvas.cleanup()
         self.zoom_canvas = None
@@ -164,13 +173,32 @@ def back_button_pressed(self):
             return
 
         if not linebuilder.xs or not linebuilder.ys:
-            # Nothing to delete
+            # Go back a line instead
+            self.restore_last_line()
             return
 
         linebuilder.remove_last_point()
 
         self.last_point_removed.emit()
 
+    def restore_last_line(self):
+        if not self.previous_linebuilders:
+            # There are no previous linebuilders to restore
+            return
+
+        self.unused_colors.append(self.lines[-1]._color)
+
+        self.linebuilder = self.previous_linebuilders.pop()
+        self.lines.pop().remove()
+
+        self.canvas.draw_idle()
+
+        if self.cycle_cursor_colors and self.lines:
+            prev_color = self.lines[-1]._color
+            self.zoom_canvas.cursor_color = prev_color
+
+        self.last_line_restored.emit()
+
     def two_click_mode_changed(self, on):
         self.two_click_mode = on
         self.zoom_frozen = False
@@ -188,7 +216,15 @@ def start(self):
 
     def add_line(self):
         ax = self.canvas.axis
-        color = next(self.color_cycler)
+        if self.unused_colors:
+            # Use the unused colors first
+            color = self.unused_colors.pop()
+        else:
+            color = next(self.color_cycler)
+
+        if self.linebuilder:
+            # Save the old linebuilders as we add new ones
+            self.previous_linebuilders.append(self.linebuilder)
 
         # empty line
         line, = ax.plot([], [], color=color, **self.line_settings)

hexrd/ui/utils/conversions.py

@@ -35,9 +35,15 @@ def cart_to_angles(xys, panel, eta_period=None, tvec_s=None, tvec_c=None,
     return ang_crds
 
 
-def angles_to_cart(angles, panel, apply_distortion=True):
-    angles = np.radians(angles)
-    return panel.angles_to_cart(angles, apply_distortion=apply_distortion)
+def angles_to_cart(angles, panel, tvec_s=None, tvec_c=None,
+                   apply_distortion=True):
+    kwargs = {
+        'tth_eta': np.radians(angles),
+        'tvec_s': tvec_s,
+        'tvec_c': tvec_c,
+        'apply_distortion': apply_distortion,
+    }
+    return panel.angles_to_cart(**kwargs)
 
 
 def angles_to_pixels(angles, panel):