MPFB (MakeHuman Plugin For Blender)

NodeService is a collection of static methods used to manage and manipulate Blender shader node trees and nodes within MPFB. It serves as the primary interface for all shader-related operations, including node creation, destruction, querying, and link management.

Key Capabilities:

• Node Tree Lifecycle: Creating, destroying, and clearing node trees.
• Node Creation: Generic and type-specific methods for adding nodes.
• Node Queries: Finding nodes by name, type, or class.
• Socket Operations: Finding sockets and getting/setting default values.
• Link Management: Creating and removing connections between nodes.
• Bulk Operations: Applying entire node tree configurations from dictionary definitions.
• Custom Node Groups: Managing MPFB's composite shader node groups.

Serialization Formats:

• v1 (Legacy): Older serialization format.
• v2 (Current): Robust format providing complete node information, including socket identifiers and attribute metadata, ensuring compatibility across Blender versions.

Note: All methods in NodeService are static; do not attempt to instantiate the class.

The MaterialService is a static service responsible for the lifecycle and management of materials assigned to Blender objects within MPFB. It handles creation, identification, modification, and management of various material types.

Supported Material Types:

• MakeSkin: The standard MakeHuman material format.
• enhanced skin: Procedural skin featuring pore detail.
• layered skin: Procedural skin with color control groups.
• procedural eyes: Specialized procedural eye materials.
• game engine: Simple materials using a Principled BSDF node.

Key Capabilities:

• Lifecycle Management: Creating empty or skin-specific materials, assigning them to objects, and managing per-body-part material slots.
• Ink Layer Management: Managing stacked texture overlays (ink layers) for makeup, tattoos, and decorations on MakeSkin and layered skin materials.
• I/O: Loading and saving materials from .blend files.
• Color Management: Providing static viewport diffuse colors and a color adjustment system for applying tints.

Note: All methods in MaterialService are static; do not attempt to instantiate the class.

MakeSkinMaterial is a specialized class that extends MhMaterial to bridge the MHMAT file format with Blender's node-based material system. It is designed specifically for the MakeSkin workflow.

Workflow Directions

1. Import (MHMAT → Blender)

Use apply_node_tree to load a makeskin.json node-tree template. The method automatically substitutes $variable placeholders (like texture paths and color values) from the MHMAT settings into the template and applies it to a Blender material via NodeService.

2. Export (Blender → MHMAT)

Use populate_from_object to scan an existing Blender object's node tree (including texture nodes and Principled BSDF values) to populate the material's settings. Once populated, use export_to_disk to serialize the data into an .mhmat file. You can optionally normalize textures by copying and renaming them to match the MHMAT base name.

import bpy
from mpfb.entities.material.makeskinmaterial import MakeSkinMaterial

# Import Example
mat = MakeSkinMaterial()
mat.populate_from_mhmat("/path/to/skin.mhmat")

blender_material = bpy.data.materials.new(name="SkinMaterial")
blender_material.use_nodes = True
mat.apply_node_tree(blender_material)

# Export Example
obj = bpy.context.active_object
mat = MakeSkinMaterial()
mat.populate_from_object(obj)

error = mat.check_that_all_textures_are_saved(
    obj,
    mhmat_dir="/path/to/output",
    mhmat_bn="myshirt"
)
if error:
    print("Problem:", error)
else:
    mat.export_to_disk("/path/to/output/myshirt.mhmat")

MPFB2 is licensed under the GNU General Public License version 3 (GPLv3). This is a strong copyleft license that ensures the software remains free for all users.

Key implications for developers:

• Freedom to Run and Modify: You have unlimited permission to run and modify the unmodified program.
• Copyleft Requirement: If you convey a modified version of the program, you must license the entire work as a whole under the GPLv3.
• Source Code Availability: If you distribute the software in object code form (e.g., a compiled binary), you must also provide the Corresponding Source (the preferred form for making modifications, including scripts to control installation and execution).
• No Additional Restrictions: You may not impose further restrictions on the exercise of the rights granted by the license (e.g., you cannot charge license fees or royalties for the right to use the software).
• Patent Grant: Contributors grant you a non-exclusive, worldwide, royalty-free patent license for their essential patent claims required to run/modify their contribution.