Add operator for removing unused material slots

Reviewers: campbellbarton, brecht

Reviewed By: brecht

Subscribers: brecht

Differential Revision: https://developer.blender.org/D4991

8 files changed, 87 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_curve.h b/source/blender/blenkernel/BKE_curve.h
index df1e7a7baea..51ff4673aba 100644
--- a/source/blender/blenkernel/BKE_curve.h
+++ b/source/blender/blenkernel/BKE_curve.h
@@ -109,6 +109,7 @@ void BKE_curve_transform(struct Curve *cu,
                          const bool do_props);
 void BKE_curve_translate(struct Curve *cu, float offset[3], const bool do_keys);
 void BKE_curve_material_index_remove(struct Curve *cu, int index);
+bool BKE_curve_material_index_used(struct Curve *cu, int index);
 void BKE_curve_material_index_clear(struct Curve *cu);
 bool BKE_curve_material_index_validate(struct Curve *cu);
 void BKE_curve_material_remap(struct Curve *cu, const unsigned int *remap, unsigned int remap_len);
diff --git a/source/blender/blenkernel/BKE_gpencil.h b/source/blender/blenkernel/BKE_gpencil.h
index ae1000d1b99..60e9e6b91d3 100644
--- a/source/blender/blenkernel/BKE_gpencil.h
+++ b/source/blender/blenkernel/BKE_gpencil.h
@@ -87,6 +87,7 @@ void BKE_gpencil_frame_delete_laststroke(struct bGPDlayer *gpl, struct bGPDframe
 
 /* materials */
 void BKE_gpencil_material_index_reassign(struct bGPdata *gpd, int totcol, int index);
+bool BKE_gpencil_material_index_used(struct bGPdata *gpd, int index);
 void BKE_gpencil_material_remap(struct bGPdata *gpd,
                                 const unsigned int *remap,
                                 unsigned int remap_len);
diff --git a/source/blender/blenkernel/BKE_material.h b/source/blender/blenkernel/BKE_material.h
index 268cf831456..b1200c7e608 100644
--- a/source/blender/blenkernel/BKE_material.h
+++ b/source/blender/blenkernel/BKE_material.h
@@ -90,6 +90,7 @@ void assign_matarar(struct Main *bmain, struct Object *ob, struct Material ***ma
 short BKE_object_material_slot_find_index(struct Object *ob, struct Material *ma);
 bool BKE_object_material_slot_add(struct Main *bmain, struct Object *ob);
 bool BKE_object_material_slot_remove(struct Main *bmain, struct Object *ob);
+bool BKE_object_material_slot_used(struct ID *id, short actcol);
 
 struct MaterialGPencilStyle *BKE_material_gpencil_settings_get(struct Object *ob, short act);
 
diff --git a/source/blender/blenkernel/BKE_mesh.h b/source/blender/blenkernel/BKE_mesh.h
index 3b7fe208bb6..59812df246f 100644
--- a/source/blender/blenkernel/BKE_mesh.h
+++ b/source/blender/blenkernel/BKE_mesh.h
@@ -182,6 +182,7 @@ void BKE_mesh_to_curve(struct Main *bmain,
                        struct Scene *scene,
                        struct Object *ob);
 void BKE_mesh_material_index_remove(struct Mesh *me, short index);
+bool BKE_mesh_material_index_used(struct Mesh *me, short index);
 void BKE_mesh_material_index_clear(struct Mesh *me);
 void BKE_mesh_material_remap(struct Mesh *me, const unsigned int *remap, unsigned int remap_len);
 void BKE_mesh_smooth_flag_set(struct Object *meshOb, int enableSmooth);
diff --git a/source/blender/blenkernel/intern/curve.c b/source/blender/blenkernel/intern/curve.c
index 931c0ed73d3..efdfa2c19bb 100644
--- a/source/blender/blenkernel/intern/curve.c
+++ b/source/blender/blenkernel/intern/curve.c
@@ -5313,6 +5313,32 @@ void BKE_curve_material_index_remove(Curve *cu, int index)
   }
 }
 
+bool BKE_curve_material_index_used(Curve *cu, int index)
+{
+  const int curvetype = BKE_curve_type_get(cu);
+
+  if (curvetype == OB_FONT) {
+    struct CharInfo *info = cu->strinfo;
+    int i;
+    for (i = cu->len_wchar - 1; i >= 0; i--, info++) {
+      if (info->mat_nr == index) {
+        return true;
+      }
+    }
+  }
+  else {
+    Nurb *nu;
+
+    for (nu = cu->nurb.first; nu; nu = nu->next) {
+      if (nu->mat_nr == index) {
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
 void BKE_curve_material_index_clear(Curve *cu)
 {
   const int curvetype = BKE_curve_type_get(cu);
diff --git a/source/blender/blenkernel/intern/gpencil.c b/source/blender/blenkernel/intern/gpencil.c
index 058c0d10b8e..7d732235f7e 100644
--- a/source/blender/blenkernel/intern/gpencil.c
+++ b/source/blender/blenkernel/intern/gpencil.c
@@ -1662,6 +1662,22 @@ void BKE_gpencil_material_index_reassign(bGPdata *gpd, int totcol, int index)
   }
 }
 
+/* remove strokes using a material */
+bool BKE_gpencil_material_index_used(bGPdata *gpd, int index)
+{
+  for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+    for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+      for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+        if (gps->mat_nr == index) {
+          return true;
+        }
+      }
+    }
+  }
+
+  return false;
+}
+
 void BKE_gpencil_material_remap(struct bGPdata *gpd,
                                 const unsigned int *remap,
                                 unsigned int remap_len)
diff --git a/source/blender/blenkernel/intern/material.c b/source/blender/blenkernel/intern/material.c
index 391af8b96ab..1382b863637 100644
--- a/source/blender/blenkernel/intern/material.c
+++ b/source/blender/blenkernel/intern/material.c
@@ -366,6 +366,26 @@ static void material_data_index_remove_id(ID *id, short index)
   }
 }
 
+bool BKE_object_material_slot_used(ID *id, short actcol)
+{
+  /* ensure we don't try get materials from non-obdata */
+  BLI_assert(OB_DATA_SUPPORT_ID(GS(id->name)));
+
+  switch (GS(id->name)) {
+    case ID_ME:
+      return BKE_mesh_material_index_used((Mesh *)id, actcol - 1);
+    case ID_CU:
+      return BKE_curve_material_index_used((Curve *)id, actcol - 1);
+    case ID_MB:
+      /* meta-elems don't have materials atm */
+      return false;
+    case ID_GD:
+      return BKE_gpencil_material_index_used((bGPdata *)id, actcol - 1);
+    default:
+      return false;
+  }
+}
+
 static void material_data_index_clear_id(ID *id)
 {
   /* ensure we don't try get materials from non-obdata */
diff --git a/source/blender/blenkernel/intern/mesh.c b/source/blender/blenkernel/intern/mesh.c
index f38161546e2..7e755e54eaa 100644
--- a/source/blender/blenkernel/intern/mesh.c
+++ b/source/blender/blenkernel/intern/mesh.c
@@ -1206,6 +1206,27 @@ void BKE_mesh_material_index_remove(Mesh *me, short index)
   }
 }
 
+bool BKE_mesh_material_index_used(Mesh *me, short index)
+{
+  MPoly *mp;
+  MFace *mf;
+  int i;
+
+  for (mp = me->mpoly, i = 0; i < me->totpoly; i++, mp++) {
+    if (mp->mat_nr == index) {
+      return true;
+    }
+  }
+
+  for (mf = me->mface, i = 0; i < me->totface; i++, mf++) {
+    if (mf->mat_nr == index) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
 void BKE_mesh_material_index_clear(Mesh *me)
 {
   MPoly *mp;