Nodes: fix writing socket default values to file

Previously, `writedata` was used to store `bNodeSocket->default_value`.
There are a couple of issues with that:
* Breaks if someone tries to load the file on a big endian system (afaik).
* There is a `/* do not use for structs */` comment on `writedata`.
* Depends on `MEM_allocN_len` which should be avoided in my opinion.
* Now it is more apparent, that this should be handled by callbacks as well.

The part in `readfile.c` should work just fine still. I could also do a case
distinction there, but the code would be the same for every case for now.
Just `sock->default_value = newdataadr(fd, sock->default_value);`.

This might change, if we want to store more complex socket type specific data
that does not fit into a single struct.

Differential Revision: https://developer.blender.org/D7039

Reviewers: brecht

1 files changed, 35 insertions, 6 deletions

diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index e1cbdc89022..dece8740789 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -963,6 +963,39 @@ static void write_CurveProfile(WriteData *wd, CurveProfile *profile)
   writestruct(wd, DATA, CurveProfilePoint, profile->path_len, profile->path);
 }
 
+static void write_node_socket_default_value(WriteData *wd, bNodeSocket *sock)
+{
+  if (sock->default_value == NULL) {
+    return;
+  }
+
+  switch ((eNodeSocketDatatype)sock->type) {
+    case SOCK_FLOAT:
+      writestruct(wd, DATA, bNodeSocketValueFloat, 1, sock->default_value);
+      break;
+    case SOCK_VECTOR:
+      writestruct(wd, DATA, bNodeSocketValueVector, 1, sock->default_value);
+      break;
+    case SOCK_RGBA:
+      writestruct(wd, DATA, bNodeSocketValueRGBA, 1, sock->default_value);
+      break;
+    case SOCK_BOOLEAN:
+      writestruct(wd, DATA, bNodeSocketValueBoolean, 1, sock->default_value);
+      break;
+    case SOCK_INT:
+      writestruct(wd, DATA, bNodeSocketValueInt, 1, sock->default_value);
+      break;
+    case SOCK_STRING:
+      writestruct(wd, DATA, bNodeSocketValueString, 1, sock->default_value);
+      break;
+    case __SOCK_MESH:
+    case SOCK_CUSTOM:
+    case SOCK_SHADER:
+      BLI_assert(false);
+      break;
+  }
+}
+
 static void write_node_socket(WriteData *wd, bNodeSocket *sock)
 {
   /* actual socket writing */
@@ -972,9 +1005,7 @@ static void write_node_socket(WriteData *wd, bNodeSocket *sock)
     IDP_WriteProperty(sock->prop, wd);
   }
 
-  if (sock->default_value) {
-    writedata(wd, DATA, MEM_allocN_len(sock->default_value), sock->default_value);
-  }
+  write_node_socket_default_value(wd, sock);
 }
 static void write_node_socket_interface(WriteData *wd, bNodeSocket *sock)
 {
@@ -985,9 +1016,7 @@ static void write_node_socket_interface(WriteData *wd, bNodeSocket *sock)
     IDP_WriteProperty(sock->prop, wd);
   }
 
-  if (sock->default_value) {
-    writedata(wd, DATA, MEM_allocN_len(sock->default_value), sock->default_value);
-  }
+  write_node_socket_default_value(wd, sock);
 }
 /* this is only direct data, tree itself should have been written */
 static void write_nodetree_nolib(WriteData *wd, bNodeTree *ntree)