def add_material()

in image_generation/utils.py [0:0]

• 22 lines of code
• 4 McCabe index (conditional complexity)

def add_material(name, **properties):
  """
  Create a new material and assign it to the active object. "name" should be the
  name of a material that has been previously loaded using load_materials.
  """
  # Figure out how many materials are already in the scene
  mat_count = len(bpy.data.materials)

  # Create a new material; it is not attached to anything and
  # it will be called "Material"
  bpy.ops.material.new()

  # Get a reference to the material we just created and rename it;
  # then the next time we make a new material it will still be called
  # "Material" and we will still be able to look it up by name
  mat = bpy.data.materials['Material']
  mat.name = 'Material_%d' % mat_count

  # Attach the new material to the active object
  # Make sure it doesn't already have materials
  obj = bpy.context.active_object
  assert len(obj.data.materials) == 0
  obj.data.materials.append(mat)

  # Find the output node of the new material
  output_node = None
  for n in mat.node_tree.nodes:
    if n.name == 'Material Output':
      output_node = n
      break

  # Add a new GroupNode to the node tree of the active material,
  # and copy the node tree from the preloaded node group to the
  # new group node. This copying seems to happen by-value, so
  # we can create multiple materials of the same type without them
  # clobbering each other
  group_node = mat.node_tree.nodes.new('ShaderNodeGroup')
  group_node.node_tree = bpy.data.node_groups[name]

  # Find and set the "Color" input of the new group node
  for inp in group_node.inputs:
    if inp.name in properties:
      inp.default_value = properties[inp.name]

  # Wire the output of the new group node to the input of
  # the MaterialOutput node
  mat.node_tree.links.new(
      group_node.outputs['Shader'],
      output_node.inputs['Surface'],
  )