import comfy import comfy.model_detection import comfy.model_management import comfy.model_patcher import comfy.utils import folder_paths import torch try: from q8_kernels.functional.ops import hadamard_transform from q8_kernels.integration.patch_transformer import ( patch_comfyui_native_transformer, patch_comfyui_transformer, ) Q8_AVAILABLE = True except ImportError: Q8_AVAILABLE = False from .nodes_registry import comfy_node def check_q8_available(): if not Q8_AVAILABLE: raise ImportError( "Q8 kernels are not available. To use this feature install the q8_kernels package from here:." "https://github.com/Lightricks/LTX-Video-Q8-Kernels" ) @comfy_node(name="LTXQ8Patch") class LTXVQ8Patch: @classmethod def INPUT_TYPES(s): return { "required": { "model": ("MODEL",), "use_fp8_attention": ( "BOOLEAN", {"default": False, "tooltip": "Use FP8 attention."}, ), } } RETURN_TYPES = ("MODEL",) FUNCTION = "patch" CATEGORY = "lightricks/LTXV" TITLE = "LTXV Q8 Patcher" def patch(self, model, use_fp8_attention): check_q8_available() m = model.clone() diffusion_key = "diffusion_model" diffusion_model = m.get_model_object(diffusion_key) if diffusion_model.__class__.__name__ == "LTXVTransformer3D": transformer_key = "diffusion_model.transformer" patcher = patch_comfyui_transformer else: transformer_key = "diffusion_model" patcher = patch_comfyui_native_transformer transformer = m.get_model_object(transformer_key) patcher(transformer, use_fp8_attention, True) m.add_object_patch(transformer_key, transformer) return (m,) def idendity_quant_fn(x, t): return x.to(dtype=t) @comfy_node(name="LTXVQ8LoraModelLoader") class LTXVQ8LoraModelLoader: def __init__(self): self.loaded_lora = None @classmethod def INPUT_TYPES(s): return { "required": { "model": ("MODEL",), "lora_name": (folder_paths.get_filename_list("loras"),), "strength_model": ( "FLOAT", {"default": 1.0, "min": -100.0, "max": 100.0, "step": 0.01}, ), } } RETURN_TYPES = ("MODEL",) CATEGORY = "lightricks/LTXV" FUNCTION = "load_lora_model_only" def load_lora(self, model, lora_name, strength_model): quant_fn = hadamard_transform is_patched_transformer = getattr( model.get_model_object("diffusion_model"), "is_patched", False ) if not is_patched_transformer or not Q8_AVAILABLE: raise ValueError( "LTXV Q8 Patcher is not applied to the model. Please use LTXQ8Patch node before loading lora or install q8_kernels." ) if strength_model == 0: return model lora_path = folder_paths.get_full_path_or_raise("loras", lora_name) lora = None if self.loaded_lora is not None: if self.loaded_lora[0] == lora_path: lora = self.loaded_lora[1] else: self.loaded_lora = None if lora is None: lora = comfy.utils.load_torch_file(lora_path, safe_load=True) new_lora = {} for k in lora: device = lora[k].device if lora[k].ndim == 2: if "lora_A" in k: new_lora[k] = quant_fn( lora[k].to(device="cuda", dtype=torch.bfloat16), out_type=torch.bfloat16, ).to(device) else: new_lora[k] = lora[k] self.loaded_lora = (lora_path, new_lora) model_lora, _ = comfy.sd.load_lora_for_models( model, None, new_lora, strength_model, 0 ) return model_lora def load_lora_model_only(self, model, lora_name, strength_model): return (self.load_lora(model, lora_name, strength_model),)