Refactor: Rename Object->obmat to Object->object_to_world

Motivation is to disambiguate on the naming level what the matrix
actually means. It is very easy to understand the meaning backwards,
especially since in Python the name goes the opposite way (it is
called `world_matrix` in the Python API).

It is important to disambiguate the naming without making developers
to look into the comment in the header file (which is also not super
clear either). Additionally, more clear naming facilitates the unit
verification (or, in this case, space validation) when reading an
expression.

This patch calls the matrix `object_to_world` which makes it clear
from the local code what is it exactly going on. This is only done
on DNA level, and a lot of local variables still follow the old
naming.

A DNA rename is setup in a way that there is no change on the file
level, so there should be no regressions at all.

The possibility is to add `_matrix` or `_mat` suffix to the name
to make it explicit that it is a matrix. Although, not sure if it
really helps the readability, or is it something redundant.

Differential Revision: https://developer.blender.org/D16328

1 files changed, 11 insertions, 11 deletions

diff --git a/source/blender/editors/object/object_relations.c b/source/blender/editors/object/object_relations.c
index 5da19d76259..10068def991 100644
--- a/source/blender/editors/object/object_relations.c
+++ b/source/blender/editors/object/object_relations.c
@@ -272,7 +272,7 @@ static int vertex_parent_set_exec(bContext *C, wmOperator *op)
 
           /* inverse parent matrix */
           BKE_object_workob_calc_parent(depsgraph, scene, ob, &workob);
-          invert_m4_m4(ob->parentinv, workob.obmat);
+          invert_m4_m4(ob->parentinv, workob.object_to_world);
         }
         else {
           ob->partype = PARVERT1;
@@ -280,7 +280,7 @@ static int vertex_parent_set_exec(bContext *C, wmOperator *op)
 
           /* inverse parent matrix */
           BKE_object_workob_calc_parent(depsgraph, scene, ob, &workob);
-          invert_m4_m4(ob->parentinv, workob.obmat);
+          invert_m4_m4(ob->parentinv, workob.object_to_world);
         }
       }
     }
@@ -401,7 +401,7 @@ void ED_object_parent_clear(Object *ob, const int type)
       /* remove parent, and apply the parented transform
        * result as object's local transforms */
       ob->parent = NULL;
-      BKE_object_apply_mat4(ob, ob->obmat, true, false);
+      BKE_object_apply_mat4(ob, ob->object_to_world, true, false);
       break;
     }
     case CLEAR_PARENT_INVERSE: {
@@ -584,7 +584,7 @@ bool ED_object_parent_set(ReportList *reports,
   if (keep_transform) {
     /* Was removed because of bug T23577,
      * but this can be handy in some cases too T32616, so make optional. */
-    BKE_object_apply_mat4(ob, ob->obmat, false, false);
+    BKE_object_apply_mat4(ob, ob->object_to_world, false, false);
   }
 
   /* Set the parent (except for follow-path constraint option). */
@@ -706,7 +706,7 @@ bool ED_object_parent_set(ReportList *reports,
 
     BKE_constraint_target_matrix_get(
         depsgraph, scene, con, 0, CONSTRAINT_OBTYPE_OBJECT, NULL, cmat, scene->r.cfra);
-    sub_v3_v3v3(vec, ob->obmat[3], cmat[3]);
+    sub_v3_v3v3(vec, ob->object_to_world[3], cmat[3]);
 
     copy_v3_v3(ob->loc, vec);
   }
@@ -729,7 +729,7 @@ bool ED_object_parent_set(ReportList *reports,
     ob->partype = PAROBJECT;
     BKE_object_workob_calc_parent(depsgraph, scene, ob, &workob);
 
-    invert_m4_m4(ob->parentinv, workob.obmat);
+    invert_m4_m4(ob->parentinv, workob.object_to_world);
   }
   else if (is_armature_parent && (ob->type == OB_GPENCIL) && (par->type == OB_ARMATURE)) {
     if (partype == PAR_ARMATURE) {
@@ -747,7 +747,7 @@ bool ED_object_parent_set(ReportList *reports,
     ob->partype = PAROBJECT;
     BKE_object_workob_calc_parent(depsgraph, scene, ob, &workob);
 
-    invert_m4_m4(ob->parentinv, workob.obmat);
+    invert_m4_m4(ob->parentinv, workob.object_to_world);
   }
   else if ((ob->type == OB_GPENCIL) && (par->type == OB_LATTICE)) {
     /* Add Lattice modifier */
@@ -758,12 +758,12 @@ bool ED_object_parent_set(ReportList *reports,
     ob->partype = PAROBJECT;
     BKE_object_workob_calc_parent(depsgraph, scene, ob, &workob);
 
-    invert_m4_m4(ob->parentinv, workob.obmat);
+    invert_m4_m4(ob->parentinv, workob.object_to_world);
   }
   else {
     /* calculate inverse parent matrix */
     BKE_object_workob_calc_parent(depsgraph, scene, ob, &workob);
-    invert_m4_m4(ob->parentinv, workob.obmat);
+    invert_m4_m4(ob->parentinv, workob.object_to_world);
   }
 
   DEG_id_tag_update(&ob->id, ID_RECALC_TRANSFORM | ID_RECALC_GEOMETRY);
@@ -772,7 +772,7 @@ bool ED_object_parent_set(ReportList *reports,
 
 static void parent_set_vert_find(KDTree_3d *tree, Object *child, int vert_par[3], bool is_tri)
 {
-  const float *co_find = child->obmat[3];
+  const float *co_find = child->object_to_world[3];
   if (is_tri) {
     KDTreeNearest_3d nearest[3];
     int tot;
@@ -1186,7 +1186,7 @@ static int object_track_clear_exec(bContext *C, wmOperator *op)
     }
 
     if (type == CLEAR_TRACK_KEEP_TRANSFORM) {
-      BKE_object_apply_mat4(ob, ob->obmat, true, true);
+      BKE_object_apply_mat4(ob, ob->object_to_world, true, true);
     }
   }
   CTX_DATA_END;