fix graph and white background added

python_app/gui/trace_png_export.py

@@ -8,7 +8,6 @@ preview into off-screen PNG files, letting us persist a graph for every config.
 
 from __future__ import annotations
 
-import logging
 from pathlib import Path
 
 import numpy as np
@@ -16,13 +15,9 @@ import pyqtgraph as pg
 from PyQt6.QtCore import QRectF
 from pyqtgraph.exporters import ImageExporter
 
+from python_app.gui.controllers.renderers.common import CAPTURED_TRACE_PEN
 from python_app.models.dataset_model import TraceData
-from python_app.gui.theme import PLOT_BACKGROUND
 
-logger = logging.getLogger(__name__)
-
-_MAGNITUDE_PEN = pg.mkPen("#4cc9f0", width=1.8)
-_PHASE_PEN = pg.mkPen("#f48c06", width=1.8)
 _EXPORT_SIZE = (1400, 520)
 
 
@@ -43,7 +38,6 @@ def export_trace_png(
     phase_deg = np.degrees(np.angle(samples))
 
     layout = pg.GraphicsLayoutWidget(show=False, size=_EXPORT_SIZE)
-    layout.setBackground(PLOT_BACKGROUND)
     try:
         layout.ci.addLabel(title, row=0, col=0, colspan=2)
 
@@ -51,13 +45,13 @@ def export_trace_png(
         magnitude_plot.showGrid(x=True, y=True, alpha=0.2)
         magnitude_plot.setLabel("bottom", "Frequency", units="Hz")
         magnitude_plot.setLabel("left", "Magnitude", units="dB")
-        magnitude_plot.plot(trace.frequency_hz, magnitude_db, pen=_MAGNITUDE_PEN)
+        magnitude_plot.plot(trace.frequency_hz, magnitude_db, pen=CAPTURED_TRACE_PEN)
 
         phase_plot = layout.ci.addPlot(row=1, col=1)
         phase_plot.showGrid(x=True, y=True, alpha=0.2)
         phase_plot.setLabel("bottom", "Frequency", units="Hz")
         phase_plot.setLabel("left", "Phase", units="deg")
-        phase_plot.plot(trace.frequency_hz, phase_deg, pen=_PHASE_PEN)
+        phase_plot.plot(trace.frequency_hz, phase_deg, pen=CAPTURED_TRACE_PEN)
 
         # An off-screen widget never receives a resizeEvent, so its central
         # GraphicsLayout keeps its small preferred size and both plots would be