G

Source code in core/nodeclass.py

class G:

    def __init__(self, prefix: str = ""):
        """ Group functional call

        This class is provided to expose ***Group*** nodes as functions with keyword arguments.
        When a Group named "Do Something" is created, it can be called with two syntaxes:
        - Using `Group` node: `node = Group("Do Something", ...)`
        - Using `G` function with the snake case name : `node = G().do_someting(...)`

        This facility can be particularilty usedful for projects with a lot of groups. The groups
        can be grouped by prefixes. The prefixes are hidden in the code.


        ``` python

        from geonodes import GeoNodes, Geometry, Float, Mesh, G

        with GeoNodes("Do Something", is_group=True, prefix="Utils"):

            g = Geometry()
            a = Float(3.14, "Pi")
            b = Float(6.28, "Tau")
            g += Mesh.Cube()

            g = Mesh(g)
            g.points.Pi = a + b

            g.out()

            a.out("Pi")

        with GeoNodes("Do Something Else", is_group=True, prefix="Utils"):

            g = Geometry()
            a = Float(3.14, "Pi")
            b = Float(6.28, "Tau")
            g += Mesh.Cube()

            g = Mesh(g)
            g.points.Pi = a + b

            g.out()

        with GeoNodes("Calling Groups"):

            utils = G("Utils")

            g = utils.do_something(Geometry(), pi=6.28)
            g = utils.do_something_else(g, g.pi, tau=7)
            g.out()   
        ```

        Parameters
        ----------
        prefix
            prefix to use when searching a tree

        """
        if prefix is None:
            self.prefix = ""
        else:
            self.prefix = str(prefix)
            if len(self.prefix):
                self.prefix += " "
        self.functions = {}

    # ====================================================================================================
    # Str returns a string to be compatible with prefix argument in Tree initialization

    def __str__(self):
        if self.prefix == "":
            return ""
        else:
            return self.prefix[:-1]

    # ====================================================================================================
    # Build a function from a node
    # ====================================================================================================

    @staticmethod
    def _call_group(group_name, *args, **kwargs):
        """Shared group invocation for G and decorated Python builders."""
        node = Group(group_name)
        return node.method_call(*args, **kwargs)

    def build_function(self, btree):
        """ Dynamically create a function to call the tree as Group

        The name of the function is the snake case version of the tree name.

        Parameters
        ----------
        btree : Blender GeometryNodeTree | ShaderNodeTree
            the tree

        Returns
        -------
        None
        """

        func_name = utils.snake_case(btree.name)
        if func_name in self.functions:
            return self.functions[func_name]['f']

        # ---------------------------------------------------------------------------
        # Calling the node
        # ---------------------------------------------------------------------------

        def f(*args, **kwargs):
            return self._call_group(btree.name, *args, **kwargs)

        # ---------------------------------------------------------------------------
        # Adding the function
        # ---------------------------------------------------------------------------

        self.functions[func_name] = {'f': f, 'source': ""}

        return f

    # ====================================================================================================
    # Source code
    # ====================================================================================================

    def error(self, f, exception=None):
        """ Raise an error when function call fails.

        Raises
        ------
        - NodeError

        Parameters
        ----------
        f : function
            the function in error

        exception : Exception
            the exception that was raised

        """

        spec = self.functions.get(f.__name__)
        if spec is None:
            source = f"No source code found for function: {f.__name__}. Existing functions are {list(self.functions.keys())}."
        else:
            source = spec['source']

        se = "No exception " if exception is None else str(exception)

        raise NodeError(f"Error when calling function '{f.__name__}' of group {self}.\n\n"
                        f"Signature is:\n\n{source}\n",
                        error_message = se)

    # ====================================================================================================
    # Get a tree by its name
    # ====================================================================================================

    @classmethod
    def get_tree(cls, name, tree_type = 'GeometryNodeTree'):

        for ng in bpy.data.node_groups:
            if ng.bl_idname != tree_type:
                continue
            if ng.name == name:
                return ng

        return None

    # ====================================================================================================
    # Get a tree by its snake case name
    # ====================================================================================================

    def __getattr__(self, name):

        if name in {"__dict__", "__weakref__"}:
            raise AttributeError(name)

        tree_type = Tree.current_tree()._btree.bl_idname
        groups = utils.get_available_groups(tree_type)

        target = utils.snake_case(self.prefix + name)
        group_name = utils.find_snake_case_name(target, list(groups.keys()))
        if group_name is None:
            raise AttributeError(f"Group '{self.prefix + name}' not found")

        group = blender.load_node_group(groups[group_name])

        return self.build_function(group)


    @staticmethod
    def _class_test():

        from geonodes import GeoNodes, Geometry, Float, Mesh, G

        with GeoNodes("Do Something", is_group=True, prefix="Utils"):

            g = Geometry()
            a = Float(3.14, "Pi")
            b = Float(6.28, "Tau")
            g += Mesh.Cube()

            g = Mesh(g)
            g.points.Pi = a + b

            g.out()

            a.out("Pi")

        with GeoNodes("Do Something Else", is_group=True, prefix="Utils"):

            g = Geometry()
            a = Float(3.14, "Pi")
            b = Float(6.28, "Tau")
            g += Mesh.Cube()

            g = Mesh(g)
            g.points.Pi = a + b

            g.out()

        with GeoNodes("Calling Groups"):

            utils = G("Utils")

            g = utils.do_something(Geometry(), pi=6.28)
            g = utils.do_something_else(g, g.pi, tau=7)
            g.out()  

__init__(prefix='')

Group functional call

This class is provided to expose Group nodes as functions with keyword arguments. When a Group named "Do Something" is created, it can be called with two syntaxes: - Using Group node: node = Group("Do Something", ...) - Using G function with the snake case name : node = G().do_someting(...)

This facility can be particularilty usedful for projects with a lot of groups. The groups can be grouped by prefixes. The prefixes are hidden in the code.

from geonodes import GeoNodes, Geometry, Float, Mesh, G

with GeoNodes("Do Something", is_group=True, prefix="Utils"):

    g = Geometry()
    a = Float(3.14, "Pi")
    b = Float(6.28, "Tau")
    g += Mesh.Cube()

    g = Mesh(g)
    g.points.Pi = a + b

    g.out()

    a.out("Pi")

with GeoNodes("Do Something Else", is_group=True, prefix="Utils"):

    g = Geometry()
    a = Float(3.14, "Pi")
    b = Float(6.28, "Tau")
    g += Mesh.Cube()

    g = Mesh(g)
    g.points.Pi = a + b

    g.out()

with GeoNodes("Calling Groups"):

    utils = G("Utils")

    g = utils.do_something(Geometry(), pi=6.28)
    g = utils.do_something_else(g, g.pi, tau=7)
    g.out()   

Parameters:

Name	Type	Description	Default
prefix	str	prefix to use when searching a tree	''

Source code in core/nodeclass.py

def __init__(self, prefix: str = ""):
    """ Group functional call

    This class is provided to expose ***Group*** nodes as functions with keyword arguments.
    When a Group named "Do Something" is created, it can be called with two syntaxes:
    - Using `Group` node: `node = Group("Do Something", ...)`
    - Using `G` function with the snake case name : `node = G().do_someting(...)`

    This facility can be particularilty usedful for projects with a lot of groups. The groups
    can be grouped by prefixes. The prefixes are hidden in the code.


    ``` python

    from geonodes import GeoNodes, Geometry, Float, Mesh, G

    with GeoNodes("Do Something", is_group=True, prefix="Utils"):

        g = Geometry()
        a = Float(3.14, "Pi")
        b = Float(6.28, "Tau")
        g += Mesh.Cube()

        g = Mesh(g)
        g.points.Pi = a + b

        g.out()

        a.out("Pi")

    with GeoNodes("Do Something Else", is_group=True, prefix="Utils"):

        g = Geometry()
        a = Float(3.14, "Pi")
        b = Float(6.28, "Tau")
        g += Mesh.Cube()

        g = Mesh(g)
        g.points.Pi = a + b

        g.out()

    with GeoNodes("Calling Groups"):

        utils = G("Utils")

        g = utils.do_something(Geometry(), pi=6.28)
        g = utils.do_something_else(g, g.pi, tau=7)
        g.out()   
    ```

    Parameters
    ----------
    prefix
        prefix to use when searching a tree

    """
    if prefix is None:
        self.prefix = ""
    else:
        self.prefix = str(prefix)
        if len(self.prefix):
            self.prefix += " "
    self.functions = {}

_call_group(group_name, *args, **kwargs) staticmethod

Shared group invocation for G and decorated Python builders.

Source code in core/nodeclass.py

@staticmethod
def _call_group(group_name, *args, **kwargs):
    """Shared group invocation for G and decorated Python builders."""
    node = Group(group_name)
    return node.method_call(*args, **kwargs)

build_function(btree)

Dynamically create a function to call the tree as Group

The name of the function is the snake case version of the tree name.

Parameters:

Name	Type	Description	Default
btree	Blender GeometryNodeTree | ShaderNodeTree	the tree	required

Returns:

Type	Description
None

Source code in core/nodeclass.py

def build_function(self, btree):
    """ Dynamically create a function to call the tree as Group

    The name of the function is the snake case version of the tree name.

    Parameters
    ----------
    btree : Blender GeometryNodeTree | ShaderNodeTree
        the tree

    Returns
    -------
    None
    """

    func_name = utils.snake_case(btree.name)
    if func_name in self.functions:
        return self.functions[func_name]['f']

    # ---------------------------------------------------------------------------
    # Calling the node
    # ---------------------------------------------------------------------------

    def f(*args, **kwargs):
        return self._call_group(btree.name, *args, **kwargs)

    # ---------------------------------------------------------------------------
    # Adding the function
    # ---------------------------------------------------------------------------

    self.functions[func_name] = {'f': f, 'source': ""}

    return f

error(f, exception=None)

Raise an error when function call fails.

Raises:

Type	Description
-NodeError

Parameters:

Name	Type	Description	Default
f	function	the function in error	required
exception	Exception	the exception that was raised	None

Source code in core/nodeclass.py

def error(self, f, exception=None):
    """ Raise an error when function call fails.

    Raises
    ------
    - NodeError

    Parameters
    ----------
    f : function
        the function in error

    exception : Exception
        the exception that was raised

    """

    spec = self.functions.get(f.__name__)
    if spec is None:
        source = f"No source code found for function: {f.__name__}. Existing functions are {list(self.functions.keys())}."
    else:
        source = spec['source']

    se = "No exception " if exception is None else str(exception)

    raise NodeError(f"Error when calling function '{f.__name__}' of group {self}.\n\n"
                    f"Signature is:\n\n{source}\n",
                    error_message = se)