From a94b3044b0e1606873b335db2b4c75b52f59d830 Mon Sep 17 00:00:00 2001
From: Zack Buhman <zack@buhman.org>
Date: Thu, 8 Jan 2026 19:18:50 -0600
Subject: [PATCH] restore support for non-animated meshes

---
 render_cpp.py | 11 ++++++++++-
 tree.py       |  7 ++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/render_cpp.py b/render_cpp.py
index 35c35cf..81e4326 100644
--- a/render_cpp.py
+++ b/render_cpp.py
@@ -119,7 +119,7 @@ def render_nodes(gltf):
             print(f"mesh node {node_ix}", file=sys.stderr)
 
         skin = f"&skin_{node['skin']}" if "skin" in node else "NULL"
-        mesh = f"&mesh_{node['skin']}" if "mesh" in node else "NULL"
+        mesh = f"&mesh_{node['mesh']}" if "mesh" in node else "NULL"
 
         scale = (1, 1, 1)
         translation = (0, 0, 0)
@@ -154,6 +154,9 @@ def render_nodes_extern(gltf):
     yield f'const int nodes__length = {len(gltf.json["nodes"])};'
 
 def render_skins(gltf):
+    if "skins" not in gltf.json:
+        return
+
     for skin_ix, skin in enumerate(gltf.json["skins"]):
         yield f"const int skin_{skin_ix}__joints[] = {{"
         for joint in skin["joints"]:
@@ -169,6 +172,8 @@ def render_skins(gltf):
         yield "};"
 
 def render_skins_extern(gltf):
+    if "skins" not in gltf.json:
+        return
     for skin_ix, skin in enumerate(gltf.json["skins"]):
         yield f"const int skin_{skin_ix}__joints__length = {len(skin['joints'])};"
 
@@ -194,12 +199,16 @@ def render_animation_channels(animation_ix, channels):
     yield "};"
 
 def render_animations_extern(animation_ix):
+    if "animations" not in gltf.json:
+        return
     for animation_ix, animation in enumerate(gltf.json["animations"]):
         yield f"extern const AnimationChannel animation_{animation_ix}__channels[];"
         length = len(animation["channels"])
         yield f"const int animation_{animation_ix}__channels__length = {length};"
 
 def render_animations(gltf):
+    if "animations" not in gltf.json:
+        return
     for animation_ix, animation in enumerate(gltf.json["animations"]):
         yield from render_animation_samplers(animation_ix, animation["samplers"])
         yield from render_animation_channels(animation_ix, animation["channels"])
diff --git a/tree.py b/tree.py
index 0d8bee3..3076ea7 100644
--- a/tree.py
+++ b/tree.py
@@ -11,6 +11,10 @@ def linearize_tree(node_ix, nodes):
 def build_tree(gltf):
     parents = {} # from child to parent
 
+    # fixme: hack
+    if len(gltf.json["nodes"]) == 1:
+        return {}, [0]
+
     for node_ix, node in enumerate(gltf.json["nodes"]):
         if "children" not in node:
             continue
@@ -18,7 +22,8 @@ def build_tree(gltf):
             assert child_ix not in parents
             parents[child_ix] = node_ix
 
-    root_node_ix, = [i for i in parents.values() if i not in parents]
+    root_node_ix, = set(i for i in parents.values() if i not in parents)
+    print(root_node_ix)
     traversal_order = list(linearize_tree(root_node_ix, gltf.json["nodes"]))
 
     return parents, traversal_order