handle character in the category 'nonspacing mark'

Those characters are ignored, because they decorate
the previous character.

bigtext.py

@@ -308,7 +308,7 @@ class InnerBigText(QWidget):
             column_in_line = self.x_pos_to_column(e.pos().x()) + self._left_offset
             column_in_line = min(column_in_line, line.length_in_columns())  # x was behind the last column of this line
             char_in_line = line.column_to_char(column_in_line)
-            print("%s in line %s lcolumn_in_line=%s" % (char_in_line, line_number, column_in_line))
+            # print("%s in line %s lcolumn_in_line=%s" % (char_in_line, line_number, column_in_line))
             byte_in_line = line.char_index_to_byte(char_in_line)
             current_byte = line.byte_offset() + byte_in_line
             # print("%s + %s = %s" % (line.byte_offset(), char_in_line, current_byte))
@@ -401,6 +401,7 @@ class InnerBigText(QWidget):
         # draw hightlights first - some characters may overlap to the next line
         # by drawing the background hightlights first we prevent that the hightlight
         # draws over a character
+        start = time.time()
         y_line_offset = self.char_height;
         for l in self.lines:
             highlight_ranges = []
@@ -412,6 +413,9 @@ class InnerBigText(QWidget):
             self.draw_highlights(highlight_ranges, painter, y_line_offset)
             y_line_offset = y_line_offset + self.char_height
 
+        end = time.time()
+        # print("highlight duration: %.3f" %((end-start)*1000))
+
         left_offset = int(-1 * self._left_offset * self.char_width)
         y_line_offset = self.char_height;
         for l in self.lines: