vdm_brush_baker/bakematerial.py

   1 # SPDX-FileCopyrightText: 2023 Robin Hohnsbeen
   2 #
   3 # SPDX-License-Identifier: GPL-3.0-or-later
   4
   5 import bpy
   6
   7
   8 def get_vdm_bake_material():
   9     """Creates a material that is used to bake the displacement from a plane against its UVs.
  10
  11     Returns:
  12     material: Baking material
  13     """
  14     material_name = 'VDM_baking_material'
  15     if material_name in bpy.data.materials:
  16         # Recreate material every time to ensure it is unchanged by the user which could lead to issues.
  17         # I would like to keep it directly after bake though so people could look
  18         # at how it is made, if they are interested.
  19         bpy.data.materials.remove(bpy.data.materials[material_name])
  20
  21     new_material = bpy.data.materials.new(name=material_name)
  22
  23     new_material.use_nodes = True
  24     nodes = new_material.node_tree.nodes
  25     principled_node = next(n for n in new_material.node_tree.nodes if n.type == "BSDF_PRINCIPLED")
  26     nodes.remove(principled_node)
  27     material_output = next(n for n in new_material.node_tree.nodes if n.type == "OUTPUT_MATERIAL")
  28
  29     # Create relevant nodes
  30     combine_node = nodes.new('ShaderNodeCombineXYZ')
  31
  32     separate_node1 = nodes.new('ShaderNodeSeparateXYZ')
  33     separate_node2 = nodes.new('ShaderNodeSeparateXYZ')
  34
  35     vector_subtract_node = nodes.new('ShaderNodeVectorMath')
  36     vector_subtract_node.operation = 'SUBTRACT'
  37
  38     vector_multiply_node = nodes.new('ShaderNodeVectorMath')
  39     vector_multiply_node.operation = 'MULTIPLY'
  40     vector_multiply_node.inputs[1].default_value = [2.0, 2.0, 2.0]
  41
  42     vector_add_node = nodes.new('ShaderNodeVectorMath')
  43     vector_add_node.operation = 'ADD'
  44     vector_add_node.inputs[1].default_value = [-0.5, -0.5, -0.5]
  45
  46     tex_coord_node = nodes.new('ShaderNodeTexCoord')
  47
  48     image_node = nodes.new('ShaderNodeTexImage')
  49     image_node.name = "VDMTexture"
  50
  51     # Connect nodes
  52     tree = new_material.node_tree
  53     tree.links.new(combine_node.outputs[0], material_output.inputs[0])
  54
  55     tree.links.new(separate_node1.outputs[0], combine_node.inputs[0])
  56     tree.links.new(separate_node1.outputs[1], combine_node.inputs[1])
  57
  58     tree.links.new(
  59         vector_subtract_node.outputs[0], separate_node1.inputs[0])
  60
  61     tree.links.new(
  62         vector_multiply_node.outputs[0], vector_subtract_node.inputs[1])
  63
  64     tree.links.new(
  65         vector_add_node.outputs[0], vector_multiply_node.inputs[0])
  66
  67     tree.links.new(tex_coord_node.outputs[2], vector_add_node.inputs[0])
  68     tree.links.new(
  69         tex_coord_node.outputs[3], vector_subtract_node.inputs[0])
  70     tree.links.new(tex_coord_node.outputs[3], separate_node2.inputs[0])
  71     tree.links.new(separate_node2.outputs[2], combine_node.inputs[2])
  72
  73     return bpy.data.materials[material_name]