Mesh Solidify

One of the more quietly load-bearing nodes in this whole pack. It wraps Blender's real bpy.ops.mesh.solidify operator, part of Avatar Graph, the pack that runs actual Blender inside ComfyUI's process (via the bpy Python package) to build interactive 2D-to-3D avatars, auto-generating a node for every mesh operator Blender has. Unlike the Solidify modifier (the non-destructive version most Blender users know), this is the direct mesh-editing operator - it bakes the thickness in immediately rather than adding a stack entry you can tweak later.

How it works

It takes flat or open geometry and gives it real depth: extrude a second, offset copy of the surface and stitch the edges between the two together, turning a paper-thin plane into something with actual thickness front and back. That matters here specifically because Avatar Graph's core pipeline - README-documented as Create Mesh Layer - builds meshes directly from flat, segmented image layers. Those start out genuinely flat. A perfectly flat plane can look visibly wrong under certain lighting or depth-of-field in the avatar viewer; giving a piece even a small real thickness is a cheap way to make it read as an actual object instead of a cardboard cutout.

Inputs and output

• BPY_OBJ - the mesh coming in.
• thickness (default 0.009999999776482582 - effectively 0.01, min -10000, max 10000) - how much depth to add. Negative values flip which side the offset extrudes toward.

Output is a single BPY_OBJ, now with real thickness.

Installing it

ComfyUI Manager: search "avatar-graph-comfyui", install, restart. Manually: cd ComfyUI/custom_nodes && git clone https://github.com/avatechai/avatar-graph-comfyui, then cd avatar-graph-comfyui && python -m pip install -r requirements.txt, then restart.

Python 3.10.x is the requirement to nail down first - the bpy package this pack is built on needs that exact minor version, and the README recommends a dedicated conda environment on macOS/Linux (conda create --name comfyui python=3.10) rather than trusting an existing Python install. Windows users get a prebuilt ComfyUI + Python 3.10 zip linked in the README to unzip over their install before adding the pack via Manager. Restart with --enable-cors-header (macOS also wants --force-fp16) for the live 3D preview - without it, the graph still runs fine, you just save the model manually from the pack's Avatar Main Output node instead.

Common issues

Rule out the Python version first if this pack's nodes aren't loading. On this node specifically: the default thickness (0.01) is a small Blender unit, and if your avatar mesh is scaled significantly up or down from Blender's default unit scale - which happens easily with programmatically generated geometry - that default can be effectively invisible. If nothing looks different after running this node, check scale before assuming it failed. Go too far the other direction and a thickness too large relative to the mesh's actual size can make the offset copy self-intersect, producing visibly broken or inverted-looking geometry rather than a clean solid - nudge the value up gradually on a new mesh rather than guessing a large number outright.