Cleanup: ED_view3d_win_to_delta & ED_view3d_calc_zfac usage

- Rename ED_view3d_win_to_delta `mval` argument to `xy_delta` as it
  as it was misleading since this is an screen-space offset not a region
  relative cursor position (typical use of the name `mval`).
  Also rename the variable passed to this function which also used the
  term `mval` in many places.
- Re-order the output argument of ED_view3d_win_to_delta last.
  use an r_ prefix for return arguments.
- Document how the `zfac` argument is intended to be used.
- Split ED_view3d_calc_zfac into two functions as the `r_flip` argument
  was only used in some special cases.

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/io/gpencil/intern/gpencil_io_base.cc b/source/blender/io/gpencil/intern/gpencil_io_base.cc
index 9d4311bd693..9379e72bdd9 100644
--- a/source/blender/io/gpencil/intern/gpencil_io_base.cc
+++ b/source/blender/io/gpencil/intern/gpencil_io_base.cc
@@ -158,7 +158,7 @@ void GpencilIO::create_object_list()
       float zdepth = 0;
       if (rv3d_) {
         if (rv3d_->is_persp) {
-          zdepth = ED_view3d_calc_zfac(rv3d_, object->obmat[3], nullptr);
+          zdepth = ED_view3d_calc_zfac(rv3d_, object->obmat[3]);
         }
         else {
           zdepth = -dot_v3v3(rv3d_->viewinv[2], object->obmat[3]);