add initial bake operator

This lead to a use-after-free bug when baking happens on
another thread at the same time.

@@ -0,0 +22,4 @@
+ * Reference to a slice of memory typically stored on disk.
+ */
+struct BDataSlice {
+  std::string name;

@@ -0,0 +66,4 @@
+     */
+    int64_t sharing_info_version;
+    /**
+     * Identifier of the stored data.

@@ -0,0 +72,4 @@
+  };
+
+  /**
+   * Map that is used to detect when a some data has been written previously. For that it keeps a

@@ -0,0 +78,4 @@
+   */
+  Map<const ImplicitSharingInfo *, StoredByRuntimeValue> stored_by_runtime_;
+
+  mutable std::mutex mutex_;

@@ -0,0 +80,4 @@
+
+  mutable std::mutex mutex_;
+  /**
+   * Map that is used to detect when some data has been previously loaded. This keeps strong

@@ -0,0 +238,4 @@
+{
+  const CPPType &type = data.type();
+  BLI_assert(type.is_trivial());
+  if (type.size() == 1 || type.is<ColorGeometry4b>()) {

@@ -0,0 +259,4 @@
+  }
+  if (type.is_any<float2, int2>()) {
+    return read_bdata_raw_data_with_endian(
+        bdata_reader, io_data, sizeof(float), r_data.size() * 2, r_data.data());

@@ -0,0 +263,4 @@
+  }
+  if (type.is<float3>()) {
+    return read_bdata_raw_data_with_endian(
+        bdata_reader, io_data, sizeof(float), r_data.size() * 3, r_data.data());

@@ -0,0 +286,4 @@
+      sharing_info, [&]() { return write_bdata_simple_gspan(bdata_writer, data); });
+}
+
+[[nodiscard]] static bool read_bdata_shared_simple_gspan(

@@ -0,0 +428,4 @@
+    return nullptr;
+  }
+
+  Curves *curves_id = bke::curves_new_nomain(num_points, num_curves);

@@ -0,0 +536,4 @@
+  instances->resize(num_instances);
+
+  const auto cancel = [&]() {
+    delete instances;

@@ -0,0 +576,4 @@
+                                 const BDataSharing &bdata_sharing)
+{
+  GeometrySet geometry;
+  if (Mesh *mesh = try_load_mesh(io_geometry, bdata_reader, bdata_sharing)) {

@@ -0,0 +280,4 @@
+      objects.append(object);
+    }
+  }
+

@@ -0,0 +286,4 @@
+      if (md->type == eModifierType_Nodes) {
+        NodesModifierData *nmd = reinterpret_cast<NodesModifierData *>(md);
+        const std::string bake_directory = bke::sim::get_bake_directory(*bmain, *object, *md);
+        BLI_delete(bake_directory.c_str(), true, true);

@@ -1202,3 +1202,1 @@
-  if (DEG_is_active(ctx->depsgraph)) {
-    const Scene *scene = DEG_get_input_scene(ctx->depsgraph);
-    const int start_frame = scene->r.sfra;
+  const Main *bmain = DEG_get_bmain(ctx->depsgraph);

@@ -1219,0 +1232,4 @@
+        nmd_orig->simulation_cache->reset();
+      }
+    }
+    /* Decide of a new simulation state should be created in this evaluation. */

@@ -208,0 +225,4 @@
+                                 const bke::sim::SimulationZoneState &next_state,
+                                 const float mix_factor) const
+  {
+    this->output_cached_state(params, prev_state);

@@ -66,0 +92,4 @@
+   * Adding a weak owner prevents the #ImplicitSharingInfo from being freed but not the referenced
+   * data.
+   *
+   * \note Other than with std::shared_ptr a weak user cannot be turned into a strong user. This is

@@ -66,0 +109,4 @@
+  void tag_ensured_mutable() const
+  {
+    BLI_assert(this->is_mutable());
+    /* Does not need an atomic increment, because if the data is mutable, there is only a single

@@ -1162,1 +1163,4 @@
 
+static void prepare_simulation_states_for_evaluation(
+    NodesModifierData *nmd,
+    NodesModifierData *nmd_orig,