Files
ComfyUI/comfy_extras/nodes_apg.py
2025-08-21 22:05:36 -04:00

107 lines
3.5 KiB
Python

import torch
from typing_extensions import override
from comfy_api.latest import ComfyExtension, io
def project(v0, v1):
v1 = torch.nn.functional.normalize(v1, dim=[-1, -2, -3])
v0_parallel = (v0 * v1).sum(dim=[-1, -2, -3], keepdim=True) * v1
v0_orthogonal = v0 - v0_parallel
return v0_parallel, v0_orthogonal
class APG(io.ComfyNode):
@classmethod
def define_schema(cls) -> io.Schema:
return io.Schema(
node_id="APG",
display_name="Adaptive Projected Guidance",
category="sampling/custom_sampling",
inputs=[
io.Model.Input("model"),
io.Float.Input(
"eta",
default=1.0,
min=-10.0,
max=10.0,
step=0.01,
tooltip="Controls the scale of the parallel guidance vector. Default CFG behavior at a setting of 1.",
),
io.Float.Input(
"norm_threshold",
default=5.0,
min=0.0,
max=50.0,
step=0.1,
tooltip="Normalize guidance vector to this value, normalization disable at a setting of 0.",
),
io.Float.Input(
"momentum",
default=0.0,
min=-5.0,
max=1.0,
step=0.01,
tooltip="Controls a running average of guidance during diffusion, disabled at a setting of 0.",
),
],
outputs=[io.Model.Output()],
)
@classmethod
def execute(cls, model, eta, norm_threshold, momentum) -> io.NodeOutput:
running_avg = 0
prev_sigma = None
def pre_cfg_function(args):
nonlocal running_avg, prev_sigma
if len(args["conds_out"]) == 1: return args["conds_out"]
cond = args["conds_out"][0]
uncond = args["conds_out"][1]
sigma = args["sigma"][0]
cond_scale = args["cond_scale"]
if prev_sigma is not None and sigma > prev_sigma:
running_avg = 0
prev_sigma = sigma
guidance = cond - uncond
if momentum != 0:
if not torch.is_tensor(running_avg):
running_avg = guidance
else:
running_avg = momentum * running_avg + guidance
guidance = running_avg
if norm_threshold > 0:
guidance_norm = guidance.norm(p=2, dim=[-1, -2, -3], keepdim=True)
scale = torch.minimum(
torch.ones_like(guidance_norm),
norm_threshold / guidance_norm
)
guidance = guidance * scale
guidance_parallel, guidance_orthogonal = project(guidance, cond)
modified_guidance = guidance_orthogonal + eta * guidance_parallel
modified_cond = (uncond + modified_guidance) + (cond - uncond) / cond_scale
return [modified_cond, uncond] + args["conds_out"][2:]
m = model.clone()
m.set_model_sampler_pre_cfg_function(pre_cfg_function)
return io.NodeOutput(m)
class ApgExtension(ComfyExtension):
@override
async def get_node_list(self) -> list[type[io.ComfyNode]]:
return [
APG,
]
async def comfy_entrypoint() -> ApgExtension:
return ApgExtension()