Set default processing to no tiling if first page > A3. Closes #189

pdfstitcher/ui/main_frame.py

@@ -422,9 +422,16 @@ def load_file(self, pathname, password=""):
             # only enable tiling if there are more than one page
             if len(self.in_doc.pages) > 1:
                 self.tiler = PageTiler()
-                self.io.do_tile.SetValue(1)
                 self.io.do_tile.Enable()
                 self.tt.Enable()
+
+                # check how big the pages are, and default to no tiling if they're over A3
+                first_page = self.in_doc.pages[0]
+                w, h = utils.get_page_dims(first_page, target_user_unit=1)
+                if w > 11.7 * 72 or h > 16.5 * 72:
+                    self.io.do_tile.SetValue(0)
+                else:
+                    self.io.do_tile.SetValue(1)
             else:
                 self.io.do_tile.SetValue(0)
                 self.io.do_tile.Disable()

pdfstitcher/utils.py

@@ -308,7 +308,7 @@ def get_page_dims(
 ) -> tuple[float, float]:
     """
     Helper function to calculate the page dimensions
-    Returns width, height as observed by the user
+    Returns width, height in pixels as observed by the user
     (taking rotation and UserUnit into account)
     """
     # The mediabox is typically specified as