Enhance playback speed control and performance optimizations

- Added playback speed options to the GUI for user selection.
- Implemented caching for timestamp deduplication in signal providers.
- Improved performance by using binary search for timestamp lookups.
- Adjusted thread sleep logic to avoid redundant updates in the meshcat provider.
- Increased meshcat provider's thread period for better performance.

Author: GiulioRomualdi

robot_log_visualizer/__main__.py

@@ -16,7 +16,7 @@
 
 def main():
     thread_periods = {
-        "meshcat_provider": 0.03,
+        "meshcat_provider": 0.05,
         "signal_provider": 0.03,
         "plot_animation": 0.03,
     }

robot_log_visualizer/plotter/pyqtgraph_viewer_canvas.py

@@ -10,6 +10,9 @@
 import pyqtgraph as pg  # type: ignore
 from qtpy import QtCore, QtWidgets  # type: ignore
 
+# --- Global pyqtgraph performance tuning ---
+pg.setConfigOptions(antialias=False, useOpenGL=True)
+
 from robot_log_visualizer.signal_provider.signal_provider import ProviderType
 from robot_log_visualizer.utils.utils import ColorPalette
 
@@ -55,6 +58,7 @@ def __init__(
 
         # data structures
         self._curves: Dict[str, pg.PlotDataItem] = {}
+        self._curve_fulldata: Dict[str, tuple] = {}  # key -> (x, y) full-res
         self._annotations: Dict[Point, pg.TextItem] = {}
         self._markers: Dict[Point, pg.ScatterPlotItem] = {}
         self._palette: Iterable = ColorPalette()
@@ -129,7 +133,12 @@ def resume_animation(self) -> None:  # noqa: D401
     def quit_animation(self) -> None:  # noqa: D401
         """Permanently stop the animation (e.g. when closing the tab)."""
         self._timer.stop()
-
+    def update_vline_value(self, value: float) -> None:
+        """Directly set the vline position (called from update_index)."""
+        if value == getattr(self, '_last_vline_val', None):
+            return
+        self._last_vline_val = value
+        self._vline.setValue(value)
     # -------------------------------------------------------------#
     # Qt event handlers                                            #
     # -------------------------------------------------------------#
@@ -147,6 +156,11 @@ def _init_ui(self) -> None:
         self._plot: pg.PlotWidget = pg.PlotWidget(background="w")
         self._layout.addWidget(self._plot)
 
+        # --- Performance: only render points visible in the current
+        # view-port and auto-downsample when zoomed out.
+        self._plot.setClipToView(True)
+        self._plot.setDownsampling(mode="peak")
+
         label_style = {"color": "#000000", "font-size": "12pt"}
         self._plot.setLabel("bottom", "Time [s]", **label_style)
         self._plot.setLabel("left", "Value", **label_style)
@@ -193,13 +207,18 @@ def _add_missing_curves(
             palette_color = next(self._palette)
             pen = pg.mkPen(palette_color.as_hex(), width=2)
 
+            # Pre-downsample for fast rendering (207k → ~4000 points)
+            x_ds, y_ds = self._downsample_peak(x, y)
+
             self._curves[key] = self._plot.plot(
-                x,
-                y,
+                x_ds,
+                y_ds,
                 pen=pen,
                 name="/".join(legend[1:]),
                 symbol=None,
+                clipToView=True,
             )
+            self._curve_fulldata[key] = (x, y)
 
             # For real-time mode, disable curve clickability to avoid interfering with live updates
             if self._signal_provider.provider_type == ProviderType.REALTIME:
@@ -211,13 +230,46 @@ def _remove_obsolete_curves(self, paths: Sequence[Path]) -> None:
         valid = {"/".join(p) for p in paths}
         for key in [k for k in self._curves if k not in valid]:
             self._plot.removeItem(self._curves.pop(key))
+            self._curve_fulldata.pop(key, None)
+
+    @staticmethod
+    def _downsample_peak(x, y, max_points: int = 4000):
+        """Peak-preserving downsample: keep min/max per window."""
+        n = len(x)
+        if n <= max_points:
+            return x, y
+        factor = max(1, n // (max_points // 2))
+        trim = (n // factor) * factor
+        yr = y[:trim].reshape(-1, factor)
+        xr = x[:trim].reshape(-1, factor)
+        stx = factor // 2
+        x_mid = xr[:, stx]
+        y_max_v = yr.max(axis=1)
+        y_min_v = yr.min(axis=1)
+        out_n = len(x_mid) * 2
+        x_out = np.empty(out_n, dtype=x.dtype)
+        y_out = np.empty(out_n, dtype=y.dtype)
+        x_out[0::2] = x_mid
+        x_out[1::2] = x_mid
+        y_out[0::2] = y_max_v
+        y_out[1::2] = y_min_v
+        if trim < n:
+            x_out = np.concatenate([x_out, x[trim:]])
+            y_out = np.concatenate([y_out, y[trim:]])
+        return x_out, y_out
 
     def _update_vline(self) -> None:
         """Move the vertical line to ``current_time``."""
         if self._signal_provider is None:
             return
 
-        self._vline.setValue(self._signal_provider.current_time)
+        new_val = self._signal_provider.current_time
+        # Skip the update (and the expensive repaint it triggers) when the
+        # position has not actually changed.
+        if new_val == getattr(self, '_last_vline_val', None):
+            return
+        self._last_vline_val = new_val
+        self._vline.setValue(new_val)
 
     def _update_realtime_curves(self):
         """Update all curves with the latest data from the signal provider."""

robot_log_visualizer/robot_visualizer/meshcat_provider.py

@@ -237,15 +237,23 @@ def robot_frames(self):
 
     def run(self):
         identity = np.eye(3)
+        last_index = -1
 
         while True:
             start = time.time()
 
-            index = self._signal_provider.index
             if self.state == PeriodicThreadState.running and self._is_model_loaded:
+                index = self._signal_provider.index
                 if len(self._signal_provider) == 0:
                     time.sleep(self._period)
                     continue
+                # Skip if data hasn't advanced (avoids redundant websocket sends)
+                if index == last_index:
+                    sleep_time = self._period - (time.time() - start)
+                    if sleep_time > 0:
+                        time.sleep(sleep_time)
+                    continue
+                last_index = index
                 robot_state = self._signal_provider.get_robot_state_at_index(index)
                 self.meshcat_visualizer_mutex.lock()
                 # These are the robot measured joint positions in radians

robot_log_visualizer/signal_provider/matfile_signal_provider.py

@@ -70,6 +70,10 @@ def __populate_text_logging_data(self, file_object):
 
     def __populate_numerical_data(self, file_object):
         data = {}
+        # Cache for timestamp deduplication: share identical arrays
+        ts_cache = getattr(self, '_ts_cache', {})
+        self._ts_cache = ts_cache
+
         for key, value in file_object.items():
             if not isinstance(value, h5py._hl.group.Group):
                 continue
@@ -80,7 +84,15 @@ def __populate_numerical_data(self, file_object):
             if "data" in value.keys():
                 data[key] = {}
                 data[key]["data"] = np.squeeze(np.array(value["data"]))
-                data[key]["timestamps"] = np.squeeze(np.array(value["timestamps"]))
+                raw_ts = np.squeeze(np.array(value["timestamps"]))
+
+                # Deduplicate: reuse an existing identical timestamp array
+                ts_key = (len(raw_ts), raw_ts[0], raw_ts[-1])
+                if ts_key in ts_cache and np.array_equal(ts_cache[ts_key], raw_ts):
+                    data[key]["timestamps"] = ts_cache[ts_key]
+                else:
+                    ts_cache[ts_key] = raw_ts
+                    data[key]["timestamps"] = raw_ts
 
                 # if the initial or end time has been updated we can also update the entire timestamps dataset
                 if data[key]["timestamps"][0] < self.initial_time:
@@ -131,33 +143,40 @@ def open(self, source: str) -> bool:
                     pass
             self.index = 0
 
+        # Pre-compute relative timestamps for binary search in run()
+        self._relative_timestamps = self.timestamps - self.initial_time
+
         return True
 
     def run(self):
+        prev_wall = time.time()
+        was_running = False
         while True:
             start = time.time()
             if self.state == PeriodicThreadState.running:
+                now = time.time()
+                if not was_running:
+                    # Just resumed — ignore stale elapsed time
+                    prev_wall = now
+                wall_elapsed = now - prev_wall
+                prev_wall = now
+                was_running = True
                 self.index_lock.lock()
-                tmp_index = self._index
-                self._current_time += self.period
+                self._current_time += wall_elapsed * self.playback_speed
                 self._current_time = min(
-                    self._current_time, self.timestamps[-1] - self.initial_time
+                    self._current_time, self._relative_timestamps[-1]
                 )
 
-                # find the index associated to the current time in self.timestamps
-                # this is valid since self.timestamps is sorted and self._current_time is increasing
-                while (
-                    self._current_time > self.timestamps[tmp_index] - self.initial_time
-                ):
-                    tmp_index += 1
-                    if tmp_index > len(self.timestamps):
-                        break
-
-                self._index = tmp_index
+                # Binary search (O(log n)) instead of linear scan
+                self._index = int(
+                    np.searchsorted(self._relative_timestamps, self._current_time)
+                )
 
                 self.index_lock.unlock()
 
                 self.update_index_signal.emit()
+            else:
+                was_running = False
 
             sleep_time = self.period - (time.time() - start)
             if sleep_time > 0:

robot_log_visualizer/signal_provider/signal_provider.py

@@ -87,6 +87,9 @@ def __init__(
 
         self._current_time = 0
 
+        self._playback_speed = 1.0
+        self._playback_speed_lock = QMutex()
+
         self.trajectory_span = 200
 
         self.provider_type = provider_type
@@ -143,6 +146,10 @@ def __populate_text_logging_data(self, file_object):
 
     def __populate_numerical_data(self, file_object):
         data = {}
+        # Cache for timestamp deduplication: share identical arrays
+        ts_cache = getattr(self, '_ts_cache', {})
+        self._ts_cache = ts_cache
+
         for key, value in file_object.items():
             if not isinstance(value, h5py._hl.group.Group):
                 continue
@@ -155,10 +162,18 @@ def __populate_numerical_data(self, file_object):
             if "data" in value.keys():
                 data[key] = {}
                 data[key]["data"] = np.atleast_1d(np.squeeze(np.array(value["data"])))
-                data[key]["timestamps"] = np.atleast_1d(
+                raw_ts = np.atleast_1d(
                     np.squeeze(np.array(value["timestamps"]))
                 )
 
+                # Deduplicate: reuse an existing identical timestamp array
+                ts_key = (len(raw_ts), raw_ts[0], raw_ts[-1])
+                if ts_key in ts_cache and np.array_equal(ts_cache[ts_key], raw_ts):
+                    data[key]["timestamps"] = ts_cache[ts_key]
+                else:
+                    ts_cache[ts_key] = raw_ts
+                    data[key]["timestamps"] = raw_ts
+
                 # if the initial or end time has been updated we can also update the entire timestamps dataset
                 if data[key]["timestamps"][0] < self.initial_time:
                     self.timestamps = data[key]["timestamps"]
@@ -275,6 +290,16 @@ def current_time(self):
         value = self._current_time
         return value
 
+    @property
+    def playback_speed(self):
+        locker = QMutexLocker(self._playback_speed_lock)
+        return self._playback_speed
+
+    @playback_speed.setter
+    def playback_speed(self, value):
+        locker = QMutexLocker(self._playback_speed_lock)
+        self._playback_speed = value
+
     def get_item_from_path(self, path, default_path=None):
         data = self.data[self.root_name]
 
@@ -304,7 +329,17 @@ def get_item_from_path_at_index(self, path, index, default_path=None, neighbor=0
         if self.timestamps is None or len(self.timestamps) == 0:
             return None
 
-        closest_index = np.argmin(np.abs(timestamps - self.timestamps[index]))
+        target = self.timestamps[index]
+        # Use binary search (O(log n)) instead of linear scan (O(n))
+        closest_index = np.searchsorted(timestamps, target)
+        # Clamp and pick the nearer of the two neighbors
+        if closest_index >= len(timestamps):
+            closest_index = len(timestamps) - 1
+        elif closest_index > 0 and (
+            abs(timestamps[closest_index - 1] - target)
+            <= abs(timestamps[closest_index] - target)
+        ):
+            closest_index -= 1
 
         if neighbor == 0:
             return data[closest_index, :]