利用者:Ideasman42/Blender UI Shenanigans

This page shows how to intercept every draw call in blenders python ui which can be used for some UI tricks.

First heres an example of how to do just that.

Tested to work with Blender 2.70

Intercept UI draw/poll

This is a simple example of how to intercept poll and draw functions, without making any behavioral changes.

classes = ["Panel", "Menu", "Header"]
 
 
def draw_override(func_orig, self_real, context):
    print("override draw:", self_real)
 
    ret = func_orig(self_real, context)
    return ret


def poll_override(func_orig, cls, context):
    print("override poll:", func_orig.__self__)
 
    ret = func_orig(context)
 
    return ret
 
import bpy


for cls_name in classes:
    cls = getattr(bpy.types, cls_name)
 
    for subcls in cls.__subclasses__():
        if "draw" in subcls.__dict__:  # dont want to get parents draw()
 
            def replace_draw():
                # function also serves to hold draw_orig in a local namespace
                draw_orig = subcls.draw
                def draw(self, context):
                    return draw_override(draw_orig, self, context)
                subcls.draw = draw
 
            replace_draw()
 
        if "poll" in subcls.__dict__:  # dont want to get parents poll()
            def replace_poll():
                # function also serves to hold poll_orig in a local namespace
                poll_orig = subcls.poll
                def poll(cls, context):
                    return poll_override(poll_orig, cls, context)
                subcls.poll = classmethod(poll)
 
            replace_poll()

Override layout & functions

This is the extended from the above code but extended to subclass the layout type used within draw().

In this example operators and properties are filtered out based on their names, but all sorts of things are possible with this - modifying args to functions, changing text etc.

classes = ["Panel", "Menu", "Header"]


import bpy

UILayout = bpy.types.UILayout

op_blacklist = [
    "render.render",
    "object.modifier_add",
    "object.forcefield_toggle",
    ]

prop_blacklist = [
    "Object.location",
    "Object.scale",
    "Object.rotation_euler",
    "RenderSettings.display_mode",
    ]


def filter_operator(op_id):
    if op_id in op_blacklist:
        return False
    return True


def filter_prop(data, prop):
    prop_id = "%s.%s" % (data.__class__.__name__, prop)
    if prop_id in prop_blacklist:
        return False
    return True


class OperatorProperties_FAKE:
    pass


class UILayout_FAKE(bpy.types.UILayout):
    __slots__ = ()

    def __getattribute__(self, attr):
        # ensure we always pass down UILayout_FAKE instances
        if attr in ("row", "split", "column", "box", "column_flow"):
            real_func = UILayout.__getattribute__(self, attr)

            def dummy_func(*args, **kw):
                print("    wrapped", attr)
                ret = real_func(*args, **kw)
                return UILayout_FAKE(ret)
            return dummy_func

        elif attr in ("operator", "operator_menu_enum", "operator_enum"):
            real_func = UILayout.__getattribute__(self, attr)

            def dummy_func(*args, **kw):
                print("    wrapped", attr)
                if filter_operator(args[0]):
                    ret = real_func(*args, **kw)
                else:
                    # UILayout.__getattribute__(self, "label")()
                    # may need to be set
                    ret = OperatorProperties_FAKE()
                return ret
            return dummy_func
        elif attr in ("prop", "prop_enum"):
            real_func = UILayout.__getattribute__(self, attr)

            def dummy_func(*args, **kw):
                print("    wrapped", attr)
                if filter_prop(args[0], args[1]):
                    ret = real_func(*args, **kw)
                else:
                    ret = None
                return ret
            return dummy_func
        else:
            return UILayout.__getattribute__(self, attr)

        print(self, attr)

    def operator(*args, **kw):
        print("OP")
        return super().operator(*args, **kw)


def draw_override(func_orig, self_real, context):
    if 1:
        class Wrapper(self_real.__class__):
            def __getattribute__(self, attr):
                if attr == "layout":
                    ret = self_real.layout
                    return UILayout_FAKE(ret)
                else:
                    return super().__getattr__(self, attr)

            @property
            def layout(self):
                ret = self_real.layout
                print("wrapped")
                return ret
        print(1)
        self_wrap = Wrapper(self_real)
        ret = func_orig(self_wrap, context)
    else:
        # simple, no wrapping
        ret = func_orig(self_wrap, context)

    return ret


def poll_override(func_orig, context):

    ret = func_orig(context)

    return ret


for cls_name in classes:
    cls = getattr(bpy.types, cls_name)

    for subcls in cls.__subclasses__():
        if "draw" in subcls.__dict__:  # dont want to get parents draw()

            def replace_draw():
                # function also serves to hold draw_old in a local namespace
                draw_orig = subcls.draw

                def draw(self, context):
                    return draw_override(draw_orig, self, context)
                subcls.draw = draw

            replace_draw()

        if "poll" in subcls.__dict__:  # dont want to get parents poll()
            def replace_poll():
                # function also serves to hold draw_old in a local namespace
                poll_orig = subcls.poll

                def poll(context):
                    return poll_override(poll_orig, context)
                subcls.poll = classmethod(poll)

            replace_poll()