1 files changed, 57 insertions, 1 deletions

diff --git a/source/blender/blenkernel/intern/cryptomatte.cc b/source/blender/blenkernel/intern/cryptomatte.cc
index 55426f738ff..74576b8bbbb 100644
--- a/source/blender/blenkernel/intern/cryptomatte.cc
+++ b/source/blender/blenkernel/intern/cryptomatte.cc
@@ -30,6 +30,7 @@
 #include "DNA_material_types.h"
 #include "DNA_node_types.h"
 #include "DNA_object_types.h"
+#include "DNA_scene_types.h"
 
 #include "BLI_compiler_attrs.h"
 #include "BLI_dynstr.h"
@@ -50,10 +51,13 @@
 
 struct CryptomatteSession {
   blender::Map<std::string, blender::bke::cryptomatte::CryptomatteLayer> layers;
+  /* Layer names in order of creation. */
+  blender::Vector<std::string> layer_names;
 
   CryptomatteSession();
   CryptomatteSession(const Main *bmain);
   CryptomatteSession(StampData *stamp_data);
+  CryptomatteSession(const Scene *scene);
 
   blender::bke::cryptomatte::CryptomatteLayer &add_layer(std::string layer_name);
   std::optional<std::string> operator[](float encoded_hash) const;
@@ -99,8 +103,32 @@ CryptomatteSession::CryptomatteSession(StampData *stamp_data)
       false);
 }
 
+CryptomatteSession::CryptomatteSession(const Scene *scene)
+{
+  LISTBASE_FOREACH (ViewLayer *, view_layer, &scene->view_layers) {
+    eViewLayerCryptomatteFlags cryptoflags = static_cast<eViewLayerCryptomatteFlags>(
+        view_layer->cryptomatte_flag & VIEW_LAYER_CRYPTOMATTE_ALL);
+    if (cryptoflags == 0) {
+      cryptoflags = static_cast<eViewLayerCryptomatteFlags>(VIEW_LAYER_CRYPTOMATTE_ALL);
+    }
+
+    if (cryptoflags & VIEW_LAYER_CRYPTOMATTE_OBJECT) {
+      add_layer(blender::StringRefNull(view_layer->name) + ".CryptoObject");
+    }
+    if (cryptoflags & VIEW_LAYER_CRYPTOMATTE_ASSET) {
+      add_layer(blender::StringRefNull(view_layer->name) + ".CryptoAsset");
+    }
+    if (cryptoflags & VIEW_LAYER_CRYPTOMATTE_MATERIAL) {
+      add_layer(blender::StringRefNull(view_layer->name) + ".CryptoMaterial");
+    }
+  }
+}
+
 blender::bke::cryptomatte::CryptomatteLayer &CryptomatteSession::add_layer(std::string layer_name)
 {
+  if (!layer_names.contains(layer_name)) {
+    layer_names.append(layer_name);
+  }
   return layers.lookup_or_add_default(layer_name);
 }
 
@@ -128,6 +156,12 @@ struct CryptomatteSession *BKE_cryptomatte_init_from_render_result(
   return session;
 }
 
+struct CryptomatteSession *BKE_cryptomatte_init_from_scene(const struct Scene *scene)
+{
+  CryptomatteSession *session = new CryptomatteSession(scene);
+  return session;
+}
+
 void BKE_cryptomatte_add_layer(struct CryptomatteSession *session, const char *layer_name)
 {
   session->add_layer(layer_name);
@@ -182,6 +216,21 @@ float BKE_cryptomatte_hash_to_float(uint32_t cryptomatte_hash)
   return blender::bke::cryptomatte::CryptomatteHash(cryptomatte_hash).float_encoded();
 }
 
+/* Find an ID in the given main that matches the given encoded float. */
+bool BKE_cryptomatte_find_name(const CryptomatteSession *session,
+                               const float encoded_hash,
+                               char *r_name,
+                               int name_len)
+{
+  std::optional<std::string> name = (*session)[encoded_hash];
+  if (!name) {
+    return false;
+  }
+
+  BLI_strncpy(r_name, name->c_str(), name_len);
+  return true;
+}
+
 char *BKE_cryptomatte_entries_to_matte_id(NodeCryptomatte *node_storage)
 {
   DynStr *matte_id = BLI_dynstr_new();
@@ -213,7 +262,8 @@ void BKE_cryptomatte_matte_id_to_entries(NodeCryptomatte *node_storage, const ch
   }
   /* Update the matte_id so the files can be opened in versions that don't
    * use `CryptomatteEntry`. */
-  if (matte_id != node_storage->matte_id && STREQ(node_storage->matte_id, matte_id)) {
+  if (matte_id != node_storage->matte_id && node_storage->matte_id &&
+      STREQ(node_storage->matte_id, matte_id)) {
     MEM_SAFE_FREE(node_storage->matte_id);
     node_storage->matte_id = static_cast<char *>(MEM_dupallocN(matte_id));
   }
@@ -599,4 +649,10 @@ void CryptomatteStampDataCallbackData::extract_layer_manifest(void *_data,
   blender::bke::cryptomatte::manifest::from_manifest(layer, propvalue);
 }
 
+const blender::Vector<std::string> &BKE_cryptomatte_layer_names_get(
+    const CryptomatteSession &session)
+{
+  return session.layer_names;
+}
+
 }  // namespace blender::bke::cryptomatte