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/blenkernel/intern/particle.c b/source/blender/blenkernel/intern/particle.c
index d6dd3cf0dbb..f111e2dde17 100644
--- a/source/blender/blenkernel/intern/particle.c
+++ b/source/blender/blenkernel/intern/particle.c
@@ -2370,8 +2370,8 @@ void precalc_guides(ParticleSimulationData *sim, ListBase *effectors)
                              0,
                              0);
 
-    mul_m4_v3(sim->ob->obmat, state.co);
-    mul_mat3_m4_v3(sim->ob->obmat, state.vel);
+    mul_m4_v3(sim->ob->object_to_world, state.co);
+    mul_mat3_m4_v3(sim->ob->object_to_world, state.vel);
 
     pd_point_from_particle(sim, pa, &state, &point);
 
@@ -2454,8 +2454,8 @@ bool do_guides(Depsgraph *depsgraph,
         }
       }
 
-      mul_m4_v3(eff->ob->obmat, guidevec);
-      mul_mat3_m4_v3(eff->ob->obmat, guidedir);
+      mul_m4_v3(eff->ob->object_to_world, guidevec);
+      mul_mat3_m4_v3(eff->ob->object_to_world, guidedir);
 
       normalize_v3(guidedir);
 
@@ -2956,7 +2956,7 @@ static void psys_thread_create_path(ParticleTask *task,
     psys_particle_on_emitter(
         ctx->sim.psmd, cpa_from, cpa_num, DMCACHE_ISCHILD, cpa->fuv, foffset, co, 0, 0, 0, orco);
 
-    mul_m4_v3(ob->obmat, co);
+    mul_m4_v3(ob->object_to_world, co);
 
     for (w = 0; w < 4; w++) {
       sub_v3_v3v3(off1[w], co, key[w]->co);
@@ -3419,7 +3419,7 @@ void psys_cache_paths(ParticleSimulationData *sim, float cfra, const bool use_re
       /* dynamic hair is in object space */
       /* keyed and baked are already in global space */
       if (hair_mesh) {
-        mul_m4_v3(sim->ob->obmat, ca->co);
+        mul_m4_v3(sim->ob->object_to_world, ca->co);
       }
       else if (!keyed && !baked && !(psys->flag & PSYS_GLOBAL_HAIR)) {
         mul_m4_v3(hairmat, ca->co);
@@ -3929,7 +3929,7 @@ void psys_mat_hair_to_global(
 
   psys_mat_hair_to_object(ob, mesh, from, pa, facemat);
 
-  mul_m4_m4m4(hairmat, ob->obmat, facemat);
+  mul_m4_m4m4(hairmat, ob->object_to_world, facemat);
 }
 
 /************************************************/
@@ -4661,8 +4661,8 @@ void psys_get_particle_on_path(ParticleSimulationData *sim,
       do_particle_interpolation(psys, p, pa, t, &pind, state);
 
       if (pind.mesh) {
-        mul_m4_v3(sim->ob->obmat, state->co);
-        mul_mat3_m4_v3(sim->ob->obmat, state->vel);
+        mul_m4_v3(sim->ob->object_to_world, state->co);
+        mul_mat3_m4_v3(sim->ob->object_to_world, state->vel);
       }
       else if (!keyed && !cached && !(psys->flag & PSYS_GLOBAL_HAIR)) {
         if ((pa->flag & PARS_REKEY) == 0) {
@@ -4685,7 +4685,7 @@ void psys_get_particle_on_path(ParticleSimulationData *sim,
     }
   }
   else if (totchild) {
-    // invert_m4_m4(imat, ob->obmat);
+    // invert_m4_m4(imat, ob->object_to_world);
 
     /* interpolate childcache directly if it exists */
     if (psys->childcache) {
@@ -4733,7 +4733,7 @@ void psys_get_particle_on_path(ParticleSimulationData *sim,
          * positioning it accurately to the surface of the emitter. */
         // copy_v3_v3(cpa_1st, co);
 
-        // mul_m4_v3(ob->obmat, cpa_1st);
+        // mul_m4_v3(ob->object_to_world, cpa_1st);
 
         pa = psys->particles + cpa->parent;