src/ui/bigtext/bigtext.py

@@ -131,7 +131,7 @@ class BigText(QWidget):
 # noinspection PyArgumentList,PyTypeChecker
 class InnerBigText(QWidget):
     _byte_offset = 0
-    _left_offset = 0
+    _left_offset = 0  # number of characters the horizontal scrollbar was moved to the right
     scroll_lines = 0
     longest_line = 0
 
@@ -504,22 +504,25 @@ class InnerBigText(QWidget):
         y_line_offset = self.char_height
         for line in self.lines:
             text = line.line_prepared_for_display()
-            painter.drawText(left_offset, y_line_offset, text)
+            leftmost_visible_char_index = line.column_to_char(self._left_offset)
+            rightmost_visible_char_index = line.column_to_char(self._left_offset + math.ceil(self.columns_shown()))
+            text = text[
+                   leftmost_visible_char_index:rightmost_visible_char_index]  # reduce string to the visible section before drawing
+            painter.drawText(0, y_line_offset, text)
+            # painter.drawText(left_offset, y_line_offset, text)
             y_line_offset = y_line_offset + self.char_height
 
         painter.end()
         end_ns = time.process_time_ns()
-        #print(f"paint took {(end_ns - start_ns) / 1000000.0}")
+        print(f"paint took {(end_ns - start_ns) / 1000000.0}")
 
     def draw_highlights(self, highlights: [HighlightedRange], painter: QPainter, y_line_offset: int):
 
         for highlight in highlights:
             if highlight.is_highlight_full_line():
-                left_offset = -1 * self._left_offset * self.char_width
                 y1 = y_line_offset - self.char_height + self.char_height / 7
                 height = self.char_height
-                full_width = Settings.max_line_length() * self.char_width
+                rect = QRect(0, round(y1), self.width(), round(height))
-                rect = QRect(round(left_offset), round(y1), round(full_width), round(height))
                 self.highlight_background(painter, rect, highlight.get_brush_full_line())
 
         for highlight in highlights:
@@ -529,7 +532,13 @@ class InnerBigText(QWidget):
             y1 = y_line_offset - self.char_height + self.char_height / 7
             height = self.char_height
 
-            rect = QRect(round(x1 - left_offset), round(y1), round(width), round(height))
+            left = round(x1 - left_offset)
+            if x1 + width < left_offset \
+                    or x1 > left_offset + self.width():
+                # too far left or too far right
+                continue
+
+            rect = QRect(left, round(y1), round(width), round(height))
             self.highlight_background(painter, rect, highlight.get_brush())
 
     def highlight_background(self, painter: QPainter, rect: QRect, brush: QBrush):

src/ui/bigtext/highlight_regex.py

@@ -35,6 +35,12 @@ class HighlightRegex(Highlight):
 
     def compute_highlight(self, line: Line) -> Optional[List[HighlightedRange]]:
         result = []
+
+        if len(self.query) == 0:
+            # query is empty - this would result in many hits and is quite expensive
+            # This happens with the highlighter we use for the selected text and maybe for the current filter query.
+            return result
+
         # print("execute regex: %s in %s" % (self.regex, line.line()))
         match_iter = re.finditer(self.regex, line.line())
         for match in match_iter:

src/ui/rangeslider.py

@@ -101,8 +101,9 @@ class RangeSlider(QWidget):
 
         painter.setBrush(to_qcolor("dddddd"))
         painter.setPen(to_qcolor("444444"))
-        painter.setRenderHint(PySide6.QtGui.QPainter.RenderHint.Antialiasing, True)
+        painter.setRenderHint(PySide6.QtGui.QPainter.RenderHint.Antialiasing, False)
         painter.drawLine(2, y_pixel, 18, y_pixel)
+        painter.setRenderHint(PySide6.QtGui.QPainter.RenderHint.Antialiasing, True)
         painter.drawPolygon(
             (QPoint(10, y_pixel), QPoint(18, y_pixel + 12 * direction), QPoint(2, y_pixel + 12 * direction)))