storing material as dicts

mat_dicts.py

# cool_mat must be present in current_blend
# this script is written to deal with only one specific material
# i'm looking at a way to write a generic cycles json exporter

import bpy

material_name = 'cool_mat'
materials = bpy.data.materials
nodes = materials[material_name].node_tree.nodes
links = materials[material_name].node_tree.links

print('-'*80)

print("""\
import bpy   
from mathutils import Vector\n
my_mat = bpy.data.materials.new('cool_mat')
my_mat.use_nodes = True""")

print('\nnodes = {')
for idx, node in enumerate(nodes):
    separator = ('\n}' if idx == len(nodes)-1 else ',')
    loc = tuple(round(k, 0) for k in node.location)
    print('    \'{0.name}\': [\'{0.type}\', {1}]{2}'.format(node, loc, separator))

print('')

# mix shader as two identical inputkeys.
# for node in nodes, make node, set node location
print("""\
for k, v in nodes.items():
    location = Vector(v[1])
    if not k in my_mat.node_tree.nodes:
        cur_node = my_mat.node_tree.nodes.new(v[0])
        cur_node.location = location
    else:
        my_mat.node_tree.nodes[k].location = location""")
    
print('')

for idx, link in enumerate(links):
    list_from = '[\'{0.from_node.name}\',\'{0.from_socket.name}\','
    list_to = '\'{0.to_node.name}\',\'{0.to_socket.name}\']'
    list_members = list_from + list_to
    link_name = 'link{:02d} = '.format(idx) 
    print(link_name + list_members.format(link))
print('')

print("""\
links = [link00, link01, link02, link03, link04]""")

# for link in links:
# from_node, from_socket, to_node, to_socket
print("""\
node_target = 1
for link in links:
    from_node = my_mat.node_tree.nodes[link[0]]
    output_socket = from_node.outputs[link[1]]
    to_node = my_mat.node_tree.nodes[link[2]]
    if link[0] in ['Emission', 'Diffuse BSDF']:
        input_socket = to_node.inputs[node_target]
        node_target += 1
    else:
        input_socket = to_node.inputs[link[3]]
    my_mat.node_tree.links.new(output_socket, input_socket)""")

print('')
print('nodes = my_mat.node_tree.nodes'.format(material_name))    
print('')
# Emission: col / strength
node = nodes['Emission']
emission_color = node.inputs['Color'].default_value[:]
emission_color = tuple(round(k, 0) for k in emission_color)
emission_strength = node.inputs['Strength'].default_value
print('node = nodes[\'Emission\']')
print('node.inputs[\'Color\'].default_value = {}'.format(emission_color))
print('node.inputs[\'Strength\'].default_value = {}'.format(emission_strength))
print('')

# Diffuse BSDF: col  roughness
node = nodes['Diffuse BSDF']
diffuse_color = node.inputs['Color'].default_value[:]
diffuse_color = tuple(round(k, 0) for k in diffuse_color)
diffuse_roughness = node.inputs['Roughness'].default_value
print('node = nodes[\'Diffuse BSDF\']')
print('node.inputs[\'Color\'].default_value = {}'.format(diffuse_color))
print('node.inputs[\'Roughness\'].default_value = {}'.format(diffuse_roughness))
print('')

# Noise Texture / Scale - Detail - Distortion
node = nodes['Noise Texture']
noise_scale = node.inputs['Scale'].default_value
noise_detail = node.inputs['Detail'].default_value
noise_distortion = node.inputs['Distortion'].default_value
print('node = nodes[\'Noise Texture\']')
print('node.inputs[\'Scale\'].default_value = {}'.format(noise_scale))
print('node.inputs[\'Detail\'].default_value = {}'.format(noise_detail))
print('node.inputs[\'Distortion\'].default_value = {}'.format(noise_distortion))

outputs this.py

import bpy   
from mathutils import Vector

my_mat = bpy.data.materials.new('cool_mat')
my_mat.use_nodes = True

nodes = {
    'Geometry': ['NEW_GEOMETRY', (-85.0, 598.0)],
    'Emission': ['EMISSION', (-111.0, 409.0)],
    'Diffuse BSDF': ['BSDF_DIFFUSE', (-116.0, 304.0)],
    'Mix Shader': ['MIX_SHADER', (193.0, 469.0)],
    'Material Output': ['OUTPUT_MATERIAL', (699.0, 435.0)],
    'Noise Texture': ['TEX_NOISE', (377.0, 299.0)]
}

for k, v in nodes.items():
    location = Vector(v[1])
    if not k in my_mat.node_tree.nodes:
        cur_node = my_mat.node_tree.nodes.new(v[0])
        cur_node.location = location
    else:
        my_mat.node_tree.nodes[k].location = location

# from_node, from_socket, to_node, to_socket
# unfortunately Mix Shader has two input nodes called 'Shader'
# this means you have to assign to input index instead.
link00 = ['Emission','Emission','Mix Shader','Shader']
link01 = ['Mix Shader','Shader','Material Output','Surface']
link02 = ['Diffuse BSDF','BSDF','Mix Shader','Shader']
link03 = ['Geometry','Normal','Mix Shader','Fac']
link04 = ['Noise Texture','Fac','Material Output','Displacement']

links = [link00, link01, link02, link03, link04]
node_target = 1
for link in links:
    from_node = my_mat.node_tree.nodes[link[0]]
    output_socket = from_node.outputs[link[1]]
    to_node = my_mat.node_tree.nodes[link[2]]
    if link[0] in ['Emission', 'Diffuse BSDF']:
        input_socket = to_node.inputs[node_target]
        node_target += 1
    else:
        input_socket = to_node.inputs[link[3]]
    my_mat.node_tree.links.new(output_socket, input_socket)

nodes = my_mat.node_tree.nodes

node = nodes['Emission']
node.inputs['Color'].default_value = (0.0, 1.0, 1.0, 1.0)
node.inputs['Strength'].default_value = 0.5

node = nodes['Diffuse BSDF']
node.inputs['Color'].default_value = (1.0, 0.0, 0.0, 1.0)
node.inputs['Roughness'].default_value = 0.0

node = nodes['Noise Texture']
node.inputs['Scale'].default_value = 5.0
node.inputs['Detail'].default_value = 2.0
node.inputs['Distortion'].default_value = 0.0