feat: cursor universal for 1D and 2D

* in 1D snapping to the closest curve
* 2D getting int coordinates

bec_widgets/qt_utils/crosshair.py

@@ -1,5 +1,5 @@
-import pyqtgraph as pg
 import numpy as np
+import pyqtgraph as pg
 from PyQt5.QtCore import pyqtSignal, QObject
 
 
@@ -7,11 +7,10 @@ class Crosshair(QObject):
     coordinatesChanged = pyqtSignal(float, float)
     dataPointClicked = pyqtSignal(float, float)
 
-    def __init__(self, plot_item, is_image=False, parent=None):
+    def __init__(self, plot_item, precision=None, parent=None):
         super().__init__(parent)
         self.plot_item = plot_item
-        self.data_shape = None
-        self.is_image = is_image
+        self.precision = precision
         self.v_line = pg.InfiniteLine(angle=90, movable=False)
         self.h_line = pg.InfiniteLine(angle=0, movable=False)
         self.plot_item.addItem(self.v_line, ignoreBounds=True)
@@ -21,26 +20,44 @@ class Crosshair(QObject):
         )
         self.plot_item.scene().sigMouseClicked.connect(self.mouse_clicked)
 
+    def get_data(self):
+        x_data, y_data = [], []
+        for item in self.plot_item.items:
+            if isinstance(item, pg.ImageItem):
+                return item.image, None  # Return image data for 2D plot
+            elif isinstance(item, pg.PlotDataItem):
+                x_data.extend(item.xData)
+                y_data.extend(item.yData)
+        if x_data and y_data:
+            return np.array(x_data), np.array(y_data)  # Return x and y data for 1D plot
+        return None, None
+
     def mouse_moved(self, event):
         pos = event[0]
-        if self.data_shape is not None and self.plot_item.vb.sceneBoundingRect().contains(pos):
+        if self.plot_item.vb.sceneBoundingRect().contains(pos):
             mouse_point = self.plot_item.vb.mapSceneToView(pos)
-            x = int(np.clip(np.round(mouse_point.x()), 0, self.data_shape[1] - 1))
-            y = int(np.clip(np.round(mouse_point.y()), 0, self.data_shape[0] - 1))
+            x, y = self.snap_to_data(mouse_point.x(), mouse_point.y())
             self.v_line.setPos(x)
             self.h_line.setPos(y)
             self.coordinatesChanged.emit(x, y)
 
     def mouse_clicked(self, event):
-        if self.data_shape is not None and self.plot_item.vb.sceneBoundingRect().contains(
-            event._scenePos
-        ):
+        if self.plot_item.vb.sceneBoundingRect().contains(event._scenePos):
             mouse_point = self.plot_item.vb.mapSceneToView(event._scenePos)
-            x = int(np.clip(np.round(mouse_point.x()), 0, self.data_shape[1] - 1))
-            y = int(np.clip(np.round(mouse_point.y()), 0, self.data_shape[0] - 1))
-            self.v_line.setPos(x)
-            self.h_line.setPos(y)
+            x, y = self.snap_to_data(mouse_point.x(), mouse_point.y())
             self.dataPointClicked.emit(x, y)
 
-    def set_data_shape(self, shape):
-        self.data_shape = shape
+    def snap_to_data(self, x, y):
+        x_data, y_data = self.get_data()
+        if x_data is not None and y_data is not None:
+            distance = (x_data - x) ** 2 + (y_data - y) ** 2
+            index = np.argmin(distance)
+            x, y = x_data[index], y_data[index]
+            if self.precision is not None:
+                x, y = round(x, self.precision), round(y, self.precision)
+            return x, y
+        elif x_data is not None and y_data is None:  # For 2D plot (ImageItem)
+            x_idx = int(np.clip(x, 0, x_data.shape[1] - 1))
+            y_idx = int(np.clip(y, 0, x_data.shape[0] - 1))
+            return x_idx, y_idx
+        return x, y

bec_widgets/qt_utils/crosshair_example.py

@@ -19,14 +19,13 @@ label_1d_move = win.addLabel("1D move label", row=0, col=0)
 label_1d_click = win.addLabel("1D click label", row=1, col=0)
 plot_item_1d = win.addPlot(row=2, col=0)
 x_data = np.linspace(0, 10, 1000)
-y_data = np.sin(x_data)
-plot_item_1d.plot(x_data, y_data)
-#
-crosshair_1d = add_crosshair(plot_item_1d)
-crosshair_1d.set_data_shape((len(y_data), len(x_data)))
+y_data_sine = np.sin(x_data)
+y_data_cosine = np.cos(x_data)
+plot_item_1d.plot(x_data, y_data_sine)
+plot_item_1d.plot(x_data, y_data_cosine)
+crosshair_1d = Crosshair(plot_item_1d, precision=2)
 
 
-#
 def on_coordinates_changed_1d(x, y):
     label_1d_move.setText(f"1D Moved: ({x}, {y})")
 
@@ -35,7 +34,6 @@ def on_data_point_clicked_1d(x, y):
     label_1d_click.setText(f"1D Clicked: ({x}, {y})")
 
 
-#
 crosshair_1d.coordinatesChanged.connect(on_coordinates_changed_1d)
 crosshair_1d.dataPointClicked.connect(on_data_point_clicked_1d)
 
@@ -50,11 +48,9 @@ img = np.random.normal(size=(100, 100))
 image_item = pg.ImageItem(img)
 plot_item_2d.addItem(image_item)
 
-crosshair_2d = add_crosshair(plot_item_2d, is_image=True)
-crosshair_2d.set_data_shape(img.shape)
+crosshair_2d = Crosshair(plot_item_2d, precision=2)
 
 
-#
 def on_coordinates_changed_2d(x, y):
     label_2d_move.setText(f"2D Moved: ({x}, {y})")