Cleanup: Remove scene frame macros (`CFRA` et al.)

Removes the following macros for scene/render frame values:
- `CFRA`
- `SUBFRA`
- `SFRA`
- `EFRA`

These macros don't add much, other than saving a few characters when typing.
It's not immediately clear what they refer to, they just hide what they
actually access. Just be explicit and clear about that.
Plus these macros gave read and write access to the variables, so eyesores like
this would be done (eyesore because it looks like assigning to a constant):
```
CFRA = some_frame_nbr;
```

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D15311

1 files changed, 3 insertions, 3 deletions

diff --git a/source/blender/io/wavefront_obj/exporter/obj_exporter.cc b/source/blender/io/wavefront_obj/exporter/obj_exporter.cc
index b0938084efb..77d4f6268bc 100644
--- a/source/blender/io/wavefront_obj/exporter/obj_exporter.cc
+++ b/source/blender/io/wavefront_obj/exporter/obj_exporter.cc
@@ -323,7 +323,7 @@ void exporter_main(bContext *C, const OBJExportParams &export_params)
 
   char filepath_with_frames[FILE_MAX];
   /* Used to reset the Scene to its original state. */
-  const int original_frame = CFRA;
+  const int original_frame = scene->r.cfra;
 
   for (int frame = export_params.start_frame; frame <= export_params.end_frame; frame++) {
     const bool filepath_ok = append_frame_to_filename(filepath, frame, filepath_with_frames);
@@ -332,11 +332,11 @@ void exporter_main(bContext *C, const OBJExportParams &export_params)
       return;
     }
 
-    CFRA = frame;
+    scene->r.cfra = frame;
     obj_depsgraph.update_for_newframe();
     fprintf(stderr, "Writing to %s\n", filepath_with_frames);
     export_frame(obj_depsgraph.get(), export_params, filepath_with_frames);
   }
-  CFRA = original_frame;
+  scene->r.cfra = original_frame;
 }
 }  // namespace blender::io::obj