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

2 files changed, 7 insertions, 6 deletions

diff --git a/source/blender/draw/engines/eevee/eevee_engine.c b/source/blender/draw/engines/eevee/eevee_engine.c
index 0cdeeaf314f..ffe0863fb9f 100644
--- a/source/blender/draw/engines/eevee/eevee_engine.c
+++ b/source/blender/draw/engines/eevee/eevee_engine.c
@@ -451,8 +451,8 @@ static void eevee_render_to_image(void *vedata,
   }
   EEVEE_PrivateData *g_data = ved->stl->g_data;
 
-  int initial_frame = CFRA;
-  float initial_subframe = SUBFRA;
+  int initial_frame = scene->r.cfra;
+  float initial_subframe = scene->r.subframe;
   float shuttertime = (do_motion_blur) ? scene->eevee.motion_blur_shutter : 0.0f;
   int time_steps_tot = (do_motion_blur) ? max_ii(1, scene->eevee.motion_blur_steps) : 1;
   g_data->render_timesteps = time_steps_tot;
@@ -588,7 +588,7 @@ static void eevee_render_to_image(void *vedata,
   /* Restore original viewport size. */
   DRW_render_viewport_size_set((int[2]){g_data->size_orig[0], g_data->size_orig[1]});
 
-  if (CFRA != initial_frame || SUBFRA != initial_subframe) {
+  if (scene->r.cfra != initial_frame || scene->r.subframe != initial_subframe) {
     /* Restore original frame number. This is because the render pipeline expects it. */
     RE_engine_frame_set(engine, initial_frame, initial_subframe);
   }
diff --git a/source/blender/draw/engines/overlay/overlay_extra.c b/source/blender/draw/engines/overlay/overlay_extra.c
index f875254a685..9d478310104 100644
--- a/source/blender/draw/engines/overlay/overlay_extra.c
+++ b/source/blender/draw/engines/overlay/overlay_extra.c
@@ -1353,7 +1353,7 @@ static void OVERLAY_volume_extra(OVERLAY_ExtraCallBuffers *cb,
 
   /* Don't show smoke before simulation starts, this could be made an option in the future. */
   const bool draw_velocity = (fds->draw_velocity && fds->fluid &&
-                              CFRA >= fds->point_cache[0]->startframe);
+                              scene->r.cfra >= fds->point_cache[0]->startframe);
 
   /* Show gridlines only for slices with no interpolation. */
   const bool show_gridlines = (fds->show_gridlines && fds->fluid &&
@@ -1546,8 +1546,9 @@ void OVERLAY_extra_cache_populate(OVERLAY_Data *vedata, Object *ob)
                            (md = BKE_modifiers_findby_type(ob, eModifierType_Fluid)) &&
                            (BKE_modifier_is_enabled(scene, md, eModifierMode_Realtime)) &&
                            (((FluidModifierData *)md)->domain != NULL) &&
-                           (CFRA >= (((FluidModifierData *)md)->domain->cache_frame_start)) &&
-                           (CFRA <= (((FluidModifierData *)md)->domain->cache_frame_end));
+                           (scene->r.cfra >=
+                            (((FluidModifierData *)md)->domain->cache_frame_start)) &&
+                           (scene->r.cfra <= (((FluidModifierData *)md)->domain->cache_frame_end));
 
   float *color;
   int theme_id = DRW_object_wire_theme_get(ob, view_layer, &color);