shader-node-group

Shader Node Group

A runnable example that declares a reusable TintedGloss shader group through tree.interface.new_socket — the 4.x/5.x API that replaced tree.inputs/tree.outputs — and instances it in two materials with different parameters, following procedural-materials-and-shaders and the shader-node-group snippet.

What it witnesses: the grouping contract. Sockets declared on the interface appear on every group-node instance; both materials share ONE group datablock (users == 2); and the per-material Tint lives on the group node, not inside the group — set it inside the tree and every material changes at once. The render is the proof: two spheres, one group, two colors.

Run

# Cheap correctness check (no render) — the CI check:
blender --background --python shader_node_group.py --

# Also render a still (EEVEE on a GPU host; use --engine cycles on GPU-less hosts):
blender --background --python shader_node_group.py -- --output spheres.png
blender --background --python shader_node_group.py -- --output spheres.png --engine cycles

It exits non-zero on failure (missing interface sockets, unshared group, or identical instance parameters). The blender-smoke workflow runs the check on Blender 4.5 LTS and 5.1.