Refactor: move Constraint .blend I/O to blenkernel

Ref T76372.

4 files changed, 195 insertions, 179 deletions

diff --git a/source/blender/blenkernel/BKE_constraint.h b/source/blender/blenkernel/BKE_constraint.h
index 5ff0e7597e9..e5c4535560d 100644
--- a/source/blender/blenkernel/BKE_constraint.h
+++ b/source/blender/blenkernel/BKE_constraint.h
@@ -31,6 +31,10 @@ struct Scene;
 struct bConstraint;
 struct bConstraintTarget;
 struct bPoseChannel;
+struct BlendWriter;
+struct BlendDataReader;
+struct BlendLibReader;
+struct BlendExpander;
 
 /* ---------------------------------------------------------------------------- */
 #ifdef __cplusplus
@@ -222,6 +226,13 @@ void BKE_constraints_solve(struct Depsgraph *depsgraph,
                            struct bConstraintOb *cob,
                            float ctime);
 
+void BKE_constraint_blend_write(struct BlendWriter *writer, struct ListBase *conlist);
+void BKE_constraint_blend_read_data(struct BlendDataReader *reader, struct ListBase *lb);
+void BKE_constraint_blend_read_lib(struct BlendLibReader *reader,
+                                   struct ID *id,
+                                   struct ListBase *conlist);
+void BKE_constraint_blend_read_expand(struct BlendExpander *expander, struct ListBase *lb);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index d21529467a1..a1b53b721d3 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -21,6 +21,9 @@
  * \ingroup bke
  */
 
+/* Allow using deprecated functionality for .blend file I/O. */
+#define DNA_DEPRECATED_ALLOW
+
 #include <float.h>
 #include <math.h>
 #include <stddef.h>
@@ -80,6 +83,8 @@
 #include "DEG_depsgraph.h"
 #include "DEG_depsgraph_query.h"
 
+#include "BLO_read_write.h"
+
 #include "CLG_log.h"
 
 #ifdef WITH_PYTHON
@@ -6086,3 +6091,174 @@ void BKE_constraints_solve(struct Depsgraph *depsgraph,
     }
   }
 }
+
+void BKE_constraint_blend_write(BlendWriter *writer, ListBase *conlist)
+{
+  LISTBASE_FOREACH (bConstraint *, con, conlist) {
+    const bConstraintTypeInfo *cti = BKE_constraint_typeinfo_get(con);
+
+    /* Write the specific data */
+    if (cti && con->data) {
+      /* firstly, just write the plain con->data struct */
+      BLO_write_struct_by_name(writer, cti->structName, con->data);
+
+      /* do any constraint specific stuff */
+      switch (con->type) {
+        case CONSTRAINT_TYPE_PYTHON: {
+          bPythonConstraint *data = con->data;
+
+          /* write targets */
+          LISTBASE_FOREACH (bConstraintTarget *, ct, &data->targets) {
+            BLO_write_struct(writer, bConstraintTarget, ct);
+          }
+
+          /* Write ID Properties -- and copy this comment EXACTLY for easy finding
+           * of library blocks that implement this.*/
+          IDP_BlendWrite(writer, data->prop);
+
+          break;
+        }
+        case CONSTRAINT_TYPE_ARMATURE: {
+          bArmatureConstraint *data = con->data;
+
+          /* write targets */
+          LISTBASE_FOREACH (bConstraintTarget *, ct, &data->targets) {
+            BLO_write_struct(writer, bConstraintTarget, ct);
+          }
+
+          break;
+        }
+        case CONSTRAINT_TYPE_SPLINEIK: {
+          bSplineIKConstraint *data = con->data;
+
+          /* write points array */
+          BLO_write_float_array(writer, data->numpoints, data->points);
+
+          break;
+        }
+      }
+    }
+
+    /* Write the constraint */
+    BLO_write_struct(writer, bConstraint, con);
+  }
+}
+
+void BKE_constraint_blend_read_data(BlendDataReader *reader, ListBase *lb)
+{
+  BLO_read_list(reader, lb);
+  LISTBASE_FOREACH (bConstraint *, con, lb) {
+    BLO_read_data_address(reader, &con->data);
+
+    switch (con->type) {
+      case CONSTRAINT_TYPE_PYTHON: {
+        bPythonConstraint *data = con->data;
+
+        BLO_read_list(reader, &data->targets);
+
+        BLO_read_data_address(reader, &data->prop);
+        IDP_BlendDataRead(reader, &data->prop);
+        break;
+      }
+      case CONSTRAINT_TYPE_ARMATURE: {
+        bArmatureConstraint *data = con->data;
+
+        BLO_read_list(reader, &data->targets);
+
+        break;
+      }
+      case CONSTRAINT_TYPE_SPLINEIK: {
+        bSplineIKConstraint *data = con->data;
+
+        BLO_read_data_address(reader, &data->points);
+        break;
+      }
+      case CONSTRAINT_TYPE_KINEMATIC: {
+        bKinematicConstraint *data = con->data;
+
+        con->lin_error = 0.0f;
+        con->rot_error = 0.0f;
+
+        /* version patch for runtime flag, was not cleared in some case */
+        data->flag &= ~CONSTRAINT_IK_AUTO;
+        break;
+      }
+      case CONSTRAINT_TYPE_CHILDOF: {
+        /* XXX version patch, in older code this flag wasn't always set, and is inherent to type */
+        if (con->ownspace == CONSTRAINT_SPACE_POSE) {
+          con->flag |= CONSTRAINT_SPACEONCE;
+        }
+        break;
+      }
+      case CONSTRAINT_TYPE_TRANSFORM_CACHE: {
+        bTransformCacheConstraint *data = con->data;
+        data->reader = NULL;
+        data->reader_object_path[0] = '\0';
+      }
+    }
+  }
+}
+
+/* temp struct used to transport needed info to lib_link_constraint_cb() */
+typedef struct tConstraintLinkData {
+  BlendLibReader *reader;
+  ID *id;
+} tConstraintLinkData;
+/* callback function used to relink constraint ID-links */
+static void lib_link_constraint_cb(bConstraint *UNUSED(con),
+                                   ID **idpoin,
+                                   bool UNUSED(is_reference),
+                                   void *userdata)
+{
+  tConstraintLinkData *cld = (tConstraintLinkData *)userdata;
+  BLO_read_id_address(cld->reader, cld->id->lib, idpoin);
+}
+
+void BKE_constraint_blend_read_lib(BlendLibReader *reader, ID *id, ListBase *conlist)
+{
+  tConstraintLinkData cld;
+
+  /* legacy fixes */
+  LISTBASE_FOREACH (bConstraint *, con, conlist) {
+    /* patch for error introduced by changing constraints (dunno how) */
+    /* if con->data type changes, dna cannot resolve the pointer! (ton) */
+    if (con->data == NULL) {
+      con->type = CONSTRAINT_TYPE_NULL;
+    }
+    /* own ipo, all constraints have it */
+    BLO_read_id_address(reader, id->lib, &con->ipo); /* XXX deprecated - old animation system */
+
+    /* If linking from a library, clear 'local' library override flag. */
+    if (id->lib != NULL) {
+      con->flag &= ~CONSTRAINT_OVERRIDE_LIBRARY_LOCAL;
+    }
+  }
+
+  /* relink all ID-blocks used by the constraints */
+  cld.reader = reader;
+  cld.id = id;
+
+  BKE_constraints_id_loop(conlist, lib_link_constraint_cb, &cld);
+}
+
+/* callback function used to expand constraint ID-links */
+static void expand_constraint_cb(bConstraint *UNUSED(con),
+                                 ID **idpoin,
+                                 bool UNUSED(is_reference),
+                                 void *userdata)
+{
+  BlendExpander *expander = userdata;
+  BLO_expand(expander, *idpoin);
+}
+
+void BKE_constraint_blend_read_expand(BlendExpander *expander, ListBase *lb)
+{
+  BKE_constraints_id_loop(lb, expand_constraint_cb, expander);
+
+  /* deprecated manual expansion stuff */
+  LISTBASE_FOREACH (bConstraint *, curcon, lb) {
+    if (curcon->ipo) {
+      BLO_expand(expander, curcon->ipo); /* XXX deprecated - old animation system */
+    }
+  }
+}
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 77a1925d444..ba290989674 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -2572,103 +2572,6 @@ static void lib_link_constraint_channels(BlendLibReader *reader, ID *id, ListBas
 /** \name Read ID: Armature
  * \{ */
 
-/* temp struct used to transport needed info to lib_link_constraint_cb() */
-typedef struct tConstraintLinkData {
-  BlendLibReader *reader;
-  ID *id;
-} tConstraintLinkData;
-/* callback function used to relink constraint ID-links */
-static void lib_link_constraint_cb(bConstraint *UNUSED(con),
-                                   ID **idpoin,
-                                   bool UNUSED(is_reference),
-                                   void *userdata)
-{
-  tConstraintLinkData *cld = (tConstraintLinkData *)userdata;
-  BLO_read_id_address(cld->reader, cld->id->lib, idpoin);
-}
-
-static void lib_link_constraints(BlendLibReader *reader, ID *id, ListBase *conlist)
-{
-  tConstraintLinkData cld;
-
-  /* legacy fixes */
-  LISTBASE_FOREACH (bConstraint *, con, conlist) {
-    /* patch for error introduced by changing constraints (dunno how) */
-    /* if con->data type changes, dna cannot resolve the pointer! (ton) */
-    if (con->data == NULL) {
-      con->type = CONSTRAINT_TYPE_NULL;
-    }
-    /* own ipo, all constraints have it */
-    BLO_read_id_address(reader, id->lib, &con->ipo); /* XXX deprecated - old animation system */
-
-    /* If linking from a library, clear 'local' library override flag. */
-    if (id->lib != NULL) {
-      con->flag &= ~CONSTRAINT_OVERRIDE_LIBRARY_LOCAL;
-    }
-  }
-
-  /* relink all ID-blocks used by the constraints */
-  cld.reader = reader;
-  cld.id = id;
-
-  BKE_constraints_id_loop(conlist, lib_link_constraint_cb, &cld);
-}
-
-static void direct_link_constraints(BlendDataReader *reader, ListBase *lb)
-{
-  BLO_read_list(reader, lb);
-  LISTBASE_FOREACH (bConstraint *, con, lb) {
-    BLO_read_data_address(reader, &con->data);
-
-    switch (con->type) {
-      case CONSTRAINT_TYPE_PYTHON: {
-        bPythonConstraint *data = con->data;
-
-        BLO_read_list(reader, &data->targets);
-
-        BLO_read_data_address(reader, &data->prop);
-        IDP_BlendDataRead(reader, &data->prop);
-        break;
-      }
-      case CONSTRAINT_TYPE_ARMATURE: {
-        bArmatureConstraint *data = con->data;
-
-        BLO_read_list(reader, &data->targets);
-
-        break;
-      }
-      case CONSTRAINT_TYPE_SPLINEIK: {
-        bSplineIKConstraint *data = con->data;
-
-        BLO_read_data_address(reader, &data->points);
-        break;
-      }
-      case CONSTRAINT_TYPE_KINEMATIC: {
-        bKinematicConstraint *data = con->data;
-
-        con->lin_error = 0.0f;
-        con->rot_error = 0.0f;
-
-        /* version patch for runtime flag, was not cleared in some case */
-        data->flag &= ~CONSTRAINT_IK_AUTO;
-        break;
-      }
-      case CONSTRAINT_TYPE_CHILDOF: {
-        /* XXX version patch, in older code this flag wasn't always set, and is inherent to type */
-        if (con->ownspace == CONSTRAINT_SPACE_POSE) {
-          con->flag |= CONSTRAINT_SPACEONCE;
-        }
-        break;
-      }
-      case CONSTRAINT_TYPE_TRANSFORM_CACHE: {
-        bTransformCacheConstraint *data = con->data;
-        data->reader = NULL;
-        data->reader_object_path[0] = '\0';
-      }
-    }
-  }
-}
-
 static void lib_link_pose(BlendLibReader *reader, Object *ob, bPose *pose)
 {
   bArmature *arm = ob->data;
@@ -2702,7 +2605,7 @@ static void lib_link_pose(BlendLibReader *reader, Object *ob, bPose *pose)
   }
 
   LISTBASE_FOREACH (bPoseChannel *, pchan, &pose->chanbase) {
-    lib_link_constraints(reader, (ID *)ob, &pchan->constraints);
+    BKE_constraint_blend_read_lib(reader, (ID *)ob, &pchan->constraints);
 
     pchan->bone = BKE_armature_find_bone_name(arm, pchan->name);
 
@@ -2848,7 +2751,7 @@ static void lib_link_object(BlendLibReader *reader, Object *ob)
 
   /* WARNING! Also check expand_object(), should reflect the stuff below. */
   lib_link_pose(reader, ob, ob->pose);
-  lib_link_constraints(reader, &ob->id, &ob->constraints);
+  BKE_constraint_blend_read_lib(reader, &ob->id, &ob->constraints);
 
   /* XXX deprecated - old animation system <<< */
   lib_link_constraint_channels(reader, &ob->id, &ob->constraintChannels);
@@ -2937,7 +2840,7 @@ static void direct_link_pose(BlendDataReader *reader, bPose *pose)
     BLO_read_data_address(reader, &pchan->bbone_prev);
     BLO_read_data_address(reader, &pchan->bbone_next);
 
-    direct_link_constraints(reader, &pchan->constraints);
+    BKE_constraint_blend_read_data(reader, &pchan->constraints);
 
     BLO_read_data_address(reader, &pchan->prop);
     IDP_BlendDataRead(reader, &pchan->prop);
@@ -3111,7 +3014,7 @@ static void direct_link_object(BlendDataReader *reader, Object *ob)
   BLO_read_list(reader, &ob->particlesystem);
   BKE_particle_system_blend_read_data(reader, &ob->particlesystem);
 
-  direct_link_constraints(reader, &ob->constraints);
+  BKE_constraint_blend_read_data(reader, &ob->constraints);
 
   BLO_read_list(reader, &ob->hooks);
   while (ob->hooks.first) {
@@ -5274,28 +5177,6 @@ static void expand_id(BlendExpander *expander, ID *id)
   expand_id_embedded_id(expander, id);
 }
 
-/* callback function used to expand constraint ID-links */
-static void expand_constraint_cb(bConstraint *UNUSED(con),
-                                 ID **idpoin,
-                                 bool UNUSED(is_reference),
-                                 void *userdata)
-{
-  BlendExpander *expander = userdata;
-  BLO_expand(expander, *idpoin);
-}
-
-static void expand_constraints(BlendExpander *expander, ListBase *lb)
-{
-  BKE_constraints_id_loop(lb, expand_constraint_cb, expander);
-
-  /* deprecated manual expansion stuff */
-  LISTBASE_FOREACH (bConstraint *, curcon, lb) {
-    if (curcon->ipo) {
-      BLO_expand(expander, curcon->ipo); /* XXX deprecated - old animation system */
-    }
-  }
-}
-
 static void expand_pose(BlendExpander *expander, bPose *pose)
 {
   if (!pose) {
@@ -5303,7 +5184,7 @@ static void expand_pose(BlendExpander *expander, bPose *pose)
   }
 
   LISTBASE_FOREACH (bPoseChannel *, chan, &pose->chanbase) {
-    expand_constraints(expander, &chan->constraints);
+    BKE_constraint_blend_read_expand(expander, &chan->constraints);
     IDP_BlendReadExpand(expander, chan->prop);
     BLO_expand(expander, chan->custom);
   }
@@ -5339,7 +5220,7 @@ static void expand_object(BlendExpander *expander, Object *ob)
 
   expand_pose(expander, ob->pose);
   BLO_expand(expander, ob->poselib);
-  expand_constraints(expander, &ob->constraints);
+  BKE_constraint_blend_read_expand(expander, &ob->constraints);
 
   BLO_expand(expander, ob->gpd);
 
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index d9c629eaf4d..55527c5cbb9 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -811,58 +811,6 @@ static void write_userdef(BlendWriter *writer, const UserDef *userdef)
   }
 }
 
-static void write_constraints(BlendWriter *writer, ListBase *conlist)
-{
-  LISTBASE_FOREACH (bConstraint *, con, conlist) {
-    const bConstraintTypeInfo *cti = BKE_constraint_typeinfo_get(con);
-
-    /* Write the specific data */
-    if (cti && con->data) {
-      /* firstly, just write the plain con->data struct */
-      BLO_write_struct_by_name(writer, cti->structName, con->data);
-
-      /* do any constraint specific stuff */
-      switch (con->type) {
-        case CONSTRAINT_TYPE_PYTHON: {
-          bPythonConstraint *data = con->data;
-
-          /* write targets */
-          LISTBASE_FOREACH (bConstraintTarget *, ct, &data->targets) {
-            BLO_write_struct(writer, bConstraintTarget, ct);
-          }
-
-          /* Write ID Properties -- and copy this comment EXACTLY for easy finding
-           * of library blocks that implement this.*/
-          IDP_BlendWrite(writer, data->prop);
-
-          break;
-        }
-        case CONSTRAINT_TYPE_ARMATURE: {
-          bArmatureConstraint *data = con->data;
-
-          /* write targets */
-          LISTBASE_FOREACH (bConstraintTarget *, ct, &data->targets) {
-            BLO_write_struct(writer, bConstraintTarget, ct);
-          }
-
-          break;
-        }
-        case CONSTRAINT_TYPE_SPLINEIK: {
-          bSplineIKConstraint *data = con->data;
-
-          /* write points array */
-          BLO_write_float_array(writer, data->numpoints, data->points);
-
-          break;
-        }
-      }
-    }
-
-    /* Write the constraint */
-    BLO_write_struct(writer, bConstraint, con);
-  }
-}
-
 static void write_pose(BlendWriter *writer, bPose *pose, bArmature *arm)
 {
   /* Write each channel */
@@ -880,7 +828,7 @@ static void write_pose(BlendWriter *writer, bPose *pose, bArmature *arm)
       IDP_BlendWrite(writer, chan->prop);
     }
 
-    write_constraints(writer, &chan->constraints);
+    BKE_constraint_blend_write(writer, &chan->constraints);
 
     animviz_motionpath_blend_write(writer, chan->mpath);
 
@@ -966,7 +914,7 @@ static void write_object(BlendWriter *writer, Object *ob, const void *id_address
     write_pose(writer, ob->pose, arm);
     write_defgroups(writer, &ob->defbase);
     write_fmaps(writer, &ob->fmaps);
-    write_constraints(writer, &ob->constraints);
+    BKE_constraint_blend_write(writer, &ob->constraints);
     animviz_motionpath_blend_write(writer, ob->mpath);
 
     BLO_write_struct(writer, PartDeflect, ob->pd);