.gitignore

@@ -10,4 +10,4 @@ __pycache__
 /dist/
 /build/
 
-/docs/_build
+/docs/_build

blender_asset_tracer/blendfile/iterators.py

@@ -20,6 +20,7 @@
 # (c) 2014, Blender Foundation - Campbell Barton
 # (c) 2018, Blender Foundation - Sybren A. Stüvel
 import typing
+import copy
 
 from blender_asset_tracer import cdefs
 from . import BlendFileBlock
@@ -70,3 +71,24 @@ def modifiers(object_block: BlendFileBlock) -> typing.Iterator[BlendFileBlock]:
     # 'ob->modifiers[...]'
     mods = object_block.get_pointer((b"modifiers", b"first"))
     yield from listbase(mods, next_path=(b"modifier", b"next"))
+
+
+def dynamic_array(block: BlendFileBlock) -> typing.Iterator[BlendFileBlock]:
+    """
+    Generator that yields each element of a dynamic array as a separate block.
+    
+    Dynamic arrays are multiple contiguous elements accessed via a single pointer.
+    BAT interprets these as a single data block, making it hard to access individual elements.
+    This function divides the array into individual blocks by creating modified copies of the original block.
+    """
+
+    offset = block.file_offset
+    element_size = block.dna_type.size
+
+    for i in range(block.count):
+        new_block = copy.copy(block)
+        new_block.file_offset = offset
+        new_block.size = element_size
+
+        yield new_block
+        offset += element_size

blender_asset_tracer/cdefs.py

@@ -52,6 +52,9 @@ eModifierType_MeshSequenceCache = 52
 eModifierType_Fluid = 56
 eModifierType_Nodes = 57
 
+# NodesModifierBakeFlag
+NODES_MODIFIER_BAKE_CUSTOM_PATH = 1 << 1
+
 # DNA_particle_types.h
 PART_DRAW_OB = 7
 PART_DRAW_GR = 8
@@ -101,4 +104,4 @@ PTCACHE_PATH = b"blendcache_"
 
 # BKE_node.h
 SH_NODE_TEX_IMAGE = 143
-CMP_NODE_R_LAYERS = 221
+CMP_NODE_R_LAYERS = 221

blender_asset_tracer/trace/modifier_walkers.py

@@ -351,3 +351,48 @@ def modifier_dynamic_paint(
         yield from _walk_point_cache(
             ctx, surface_block_name, modifier.bfile, point_cache, cdefs.PTCACHE_EXT
         )
+
+
+@mod_handler(cdefs.eModifierType_Nodes)
+def modifier_nodes(
+    ctx: ModifierContext, modifier: blendfile.BlendFileBlock, block_name: bytes
+) -> typing.Iterator[result.BlockUsage]:
+    mod_directory_ptr, mod_directory_field = modifier.get(
+        b"simulation_bake_directory", return_field=True
+    )
+
+    bakes = modifier.get_pointer(b"bakes")
+
+    for bake_idx, bake in enumerate(blendfile.iterators.dynamic_array(bakes)):
+        bake_directory_ptr, bake_directory_field = bake.get(
+            b"directory", return_field=True
+        )
+
+        flag = bake.get(b"flag")
+        use_custom_directory = bool(flag & cdefs.NODES_MODIFIER_BAKE_CUSTOM_PATH)
+
+        if use_custom_directory:
+            directory_ptr = bake_directory_ptr
+            field = bake_directory_field
+            block = bake
+        else:
+            directory_ptr = mod_directory_ptr
+            field = mod_directory_field
+            block = modifier
+
+        if not directory_ptr:
+            continue
+        directory = bake.bfile.dereference_pointer(directory_ptr)
+        if not directory:
+            continue
+
+        bpath = bytes(directory.as_string(), "utf-8")
+        bake_block_name = block_name + b".bakes[%d]" % bake_idx
+
+        yield result.BlockUsage(
+            block,
+            bpath,
+            block_name=bake_block_name,
+            path_full_field=field,
+            is_sequence=True,
+        )

tests/test_blendfile_loading.py

@@ -279,6 +279,29 @@ class ArrayTest(AbstractBlendFileTest):
             self.assertEqual(name, tex.id_name)
 
 
+class DynamicArrayTest(AbstractBlendFileTest):
+    def test_dynamic_array_of_bakes(self):
+        self.bf = blendfile.BlendFile(self.blendfiles / "multiple_geometry_nodes_bakes.blend")
+        obj = self.bf.code_index[b"OB"][0]
+        assert isinstance(obj, blendfile.BlendFileBlock)
+        modifier = obj.get_pointer((b"modifiers", b"first"))
+        assert isinstance(modifier, blendfile.BlendFileBlock)
+        bakes = modifier.get_pointer(b"bakes")
+
+        bake_count = bakes.count
+        self.assertEqual(3, bake_count)
+
+        for i, bake in enumerate(blendfile.iterators.dynamic_array(bakes)):
+            if i == 0:
+                frame_start = 37
+            if i == 1:
+                frame_start = 5
+            if i == 2:
+                frame_start = 12
+
+            self.assertEqual(frame_start, bake.get(b"frame_start"))
+
+
 class CompressionRecognitionTest(AbstractBlendFileTest):
     def _find_compression_type(self, filename: str) -> magic_compression.Compression:
         path = self.blendfiles / filename