align cutoff line rendering across previews

head_extension_app.py

@@ -604,8 +604,8 @@ class HeadExtensionApp:
                 self.status.set("正在读取 DICOM 生成预览...")
                 self.cached_volume = load_dicom_volume(self.input_dir.get())
             before = crop_head_neck(sagittal_mip(self.cached_volume))
-            before = draw_cutoff_line(before, self.cached_volume.shape[0])
             after = preview_deform_2d(before, float(self.angle.get()))
+            after = draw_cutoff_line(after, self.cached_volume.shape[0])
 
             canvas = Image.new("RGB", (1120, 610), (0, 0, 0))
             draw = ImageDraw.Draw(canvas)

web_backend.py

@@ -550,8 +550,8 @@ def start_job(kind, worker, owner=None, params=None, remember_user_task=True):
 def make_preview(input_dir, angle_degrees):
     volume = load_dicom_volume(input_dir)
     before = crop_head_neck(sagittal_mip(volume))
-    before = draw_cutoff_line(before, volume.shape[0])
     after = preview_deform_2d(before, float(angle_degrees))
+    after = draw_cutoff_line(after, volume.shape[0])
 
     canvas = BytesIO()
     preview = fit_image(after, 720, 520)