PyThermostat GUI: Implement plotting

Co-authored-by: linuswck <linuswck@m-labs.hk>

pythermostat/pythermostat/gui/view/live_plot_view.py

@@ -0,0 +1,180 @@
+from PyQt6.QtCore import QObject, pyqtSlot
+from pglive.sources.data_connector import DataConnector
+from pglive.kwargs import Axis
+from pglive.sources.live_plot import LiveLinePlot
+from pglive.sources.live_axis import LiveAxis
+from collections import deque
+import pyqtgraph as pg
+from pythermostat.gui.model.thermostat import ThermostatConnectionState
+
+pg.setConfigOptions(antialias=True)
+
+
+class LiveDataPlotter(QObject):
+    def __init__(self, thermostat, live_plots):
+        super().__init__()
+        self._thermostat = thermostat
+
+        self._thermostat.report_update.connect(self.update_report)
+        self._thermostat.pid_update.connect(self.update_pid)
+        self._thermostat.connection_state_update.connect(
+            self.thermostat_state_change_handler
+        )
+
+        self.NUM_CHANNELS = len(live_plots)
+        self.graphs = []
+
+        for i, live_plot in enumerate(live_plots):
+            live_plot[0].setTitle(f"Channel {i} Temperature")
+            live_plot[1].setTitle(f"Channel {i} Current")
+            self.graphs.append(_TecGraphs(live_plot[0], live_plot[1]))
+
+    @pyqtSlot(ThermostatConnectionState)
+    def thermostat_state_change_handler(self, state):
+        if state == ThermostatConnectionState.DISCONNECTED:
+            self.clear_graphs()
+
+    def _config_connector_max_pts(self, connector, samples):
+        connector.max_points = samples
+        connector.x = deque(maxlen=int(connector.max_points))
+        connector.y = deque(maxlen=int(connector.max_points))
+
+    @pyqtSlot(int)
+    def set_max_samples(self, samples: int):
+        for graph in self.graphs:
+            self._config_connector_max_pts(graph.t_connector, samples)
+            self._config_connector_max_pts(graph.i_connector, samples)
+            self._config_connector_max_pts(graph.iset_connector, samples)
+
+    @pyqtSlot()
+    def clear_graphs(self):
+        for graph in self.graphs:
+            graph.clear()
+
+    @pyqtSlot(list)
+    def update_pid(self, pid_settings):
+        for settings in pid_settings:
+            channel = settings["channel"]
+            self.graphs[channel].update_pid(settings)
+
+    @pyqtSlot(list)
+    def update_report(self, report_data):
+        for settings in report_data:
+            channel = settings["channel"]
+            self.graphs[channel].update_report(settings)
+
+
+class _TecGraphs:
+    """The maximum number of sample points to store."""
+
+    DEFAULT_MAX_SAMPLES = 1000
+
+    def __init__(self, t_widget, i_widget):
+        self._t_widget = t_widget
+        self._i_widget = i_widget
+
+        self._t_plot = LiveLinePlot()
+        self._i_plot = LiveLinePlot(name="Measured")
+        self._iset_plot = LiveLinePlot(name="Set", pen=pg.mkPen("r"))
+
+        self._t_line = self._t_widget.getPlotItem().addLine(label="{value} °C")
+        self._t_line.setVisible(False)
+        # Hack for keeping setpoint line in plot range
+        self._t_setpoint_plot = LiveLinePlot()
+
+        for graph in t_widget, i_widget:
+            time_axis = LiveAxis(
+                "bottom",
+                text="Time since Thermostat reset",
+                **{Axis.TICK_FORMAT: Axis.DURATION},
+            )
+            time_axis.showLabel()
+            graph.setAxisItems({"bottom": time_axis})
+
+            graph.add_crosshair(pg.mkPen(color="red", width=1), {"color": "green"})
+
+            # Enable linking of axes in the graph widget's context menu
+            graph.register(
+                graph.getPlotItem().titleLabel.text  # Slight hack getting the title
+            )
+
+        temperature_axis = LiveAxis("left", text="Temperature", units="°C")
+        temperature_axis.showLabel()
+        t_widget.setAxisItems({"left": temperature_axis})
+
+        current_axis = LiveAxis("left", text="Current", units="A")
+        current_axis.showLabel()
+        i_widget.setAxisItems({"left": current_axis})
+        i_widget.addLegend(brush=(50, 50, 200, 150))
+
+        t_widget.addItem(self._t_plot)
+        t_widget.addItem(self._t_setpoint_plot)
+        i_widget.addItem(self._i_plot)
+        i_widget.addItem(self._iset_plot)
+
+        self.t_connector = DataConnector(
+            self._t_plot, max_points=self.DEFAULT_MAX_SAMPLES
+        )
+        self.t_setpoint_connector = DataConnector(self._t_setpoint_plot, max_points=1)
+        self.i_connector = DataConnector(
+            self._i_plot, max_points=self.DEFAULT_MAX_SAMPLES
+        )
+        self.iset_connector = DataConnector(
+            self._iset_plot, max_points=self.DEFAULT_MAX_SAMPLES
+        )
+
+        self.max_samples = self.DEFAULT_MAX_SAMPLES
+
+    def plot_append(self, report):
+        temperature = report["temperature"]
+        current = report["tec_i"]
+        iset = report["i_set"]
+        time = report["time"]
+
+        if temperature is not None:
+            self.t_connector.cb_append_data_point(temperature, time)
+            if self._t_line.isVisible():
+                self.t_setpoint_connector.cb_append_data_point(
+                    self._t_line.value(), time
+                )
+            else:
+                self.t_setpoint_connector.cb_append_data_point(temperature, time)
+            if current is not None:
+                self.i_connector.cb_append_data_point(current, time)
+            self.iset_connector.cb_append_data_point(iset, time)
+
+    def set_max_sample(self, samples: int):
+        for connector in self.t_connector, self.i_connector, self.iset_connector:
+            connector.max_points(samples)
+
+    def clear(self):
+        for connector in self.t_connector, self.i_connector, self.iset_connector:
+            connector.clear()
+
+    def set_t_line(self, temp=None, visible=None):
+        if visible is not None:
+            self._t_line.setVisible(visible)
+        if temp is not None:
+            self._t_line.setValue(temp)
+
+            # PyQtGraph normally does not update this text when the line
+            # is not visible, so make sure that the temperature label
+            # gets updated always, and doesn't stay at an old value.
+            self._t_line.label.setText(f"{temp} °C")
+
+    def set_max_samples(self, samples: int):
+        for graph in self.graphs:
+            graph.t_connector.max_points = samples
+            graph.i_connector.max_points = samples
+            graph.iset_connector.max_points = samples
+
+    def clear_graphs(self):
+        for graph in self.graphs:
+            graph.clear()
+
+    def update_pid(self, pid_settings):
+        self.set_t_line(temp=round(pid_settings["target"], 6))
+
+    def update_report(self, report_data):
+        self.plot_append(report_data)
+        self.set_t_line(visible=report_data["pid_engaged"])

pythermostat/pythermostat/thermostat_qt.py

@@ -13,6 +13,7 @@ from pythermostat.gui.model.thermostat import Thermostat, ThermostatConnectionSt
 from pythermostat.gui.model.pid_autotuner import PIDAutoTuner
 from pythermostat.gui.view.connection_details_menu import ConnectionDetailsMenu
 from pythermostat.gui.view.info_box import InfoBox
+from pythermostat.gui.view.live_plot_view import LiveDataPlotter
 from pythermostat.gui.view.thermostat_settings_menu import ThermostatSettingsMenu
 from pythermostat.gui.view.zero_limits_warning_view import ZeroLimitsWarningView
 
@@ -78,6 +79,15 @@ class MainWindow(QtWidgets.QMainWindow):
 
         self._thermostat.connection_error.connect(handle_connection_error)
 
+        # Graphs
+        self._channel_graphs = LiveDataPlotter(
+            self._thermostat,
+            [
+                [getattr(self, f"ch{ch}_t_graph"), getattr(self, f"ch{ch}_i_graph")]
+                for ch in range(self.NUM_CHANNELS)
+            ],
+        )
+
         # Bottom bar menus
         self.connection_details_menu = ConnectionDetailsMenu(
             self._thermostat, self.connect_btn