v1.4: LoRA Stack node (dropdown+strength UI, chainable), shipped wired into the loader

INSTRUCTIONS.md

@@ -128,17 +128,19 @@ is simpler.
 
 ## 7. LoRAs
 
-As of v1.4 the loader takes **multiple LoRAs**. Two ways, and they stack:
-
-- Pick one in the `lora_file` dropdown (loads at `lora_strength`), and/or
-- List any number in `lora_path`, separated by commas or newlines, each with
-  an optional per-LoRA strength:
-
-      my_style.safetensors@0.7, my_character.safetensors@0.9
-      F:/somewhere/else/extra.safetensors
-
-  Entries without a strength use the `lora_strength` widget. `@` and `:` both
-  work as the strength separator (Windows drive letters are handled).
+As of v1.4 the loader takes **multiple LoRAs**, and the workflow ships with
+the node for it: the **LoRA Stack** node, already wired into the Model Loader.
+
+- Pick up to three LoRAs in its dropdowns, each with its own strength slider.
+  Slots left on `(none)` do nothing.
+- Need more than three? Add another LoRA Stack node (Add Node > JoyAI-Echo >
+  JoyEcho LoRA Stack) and chain it: first node's `lora_stack` output into the
+  second node's `lora_stack` input, second node into the Model Loader.
+- Everything stacks with the Model Loader's own `lora_file` pick.
+
+Power users / automation: `lora_path` also accepts a text list — one entry per
+line or comma-separated, each with an optional strength suffix
+(`my_style.safetensors@0.7`). Same result, no extra nodes.
 
 All LoRAs are fused into the model at load, so there is no per-step cost.
 Note: LoRAs apply on the **safetensors DiT path** only — they are ignored when

__init__.py

@@ -25,6 +25,7 @@ NODE_DISPLAY_NAME_MAPPINGS = {}
 # ---------------------------------------------------------------- upstream JoyEcho nodes
 from .nodes import (
     JoyEcho_ModelLoader,
+    JoyEcho_LoraStacker,
     JoyEcho_TextEncode,
     JoyEcho_Generate,
     JoyEcho_SingleShotGenerate,
@@ -35,6 +36,7 @@ from .nodes import (
 
 NODE_CLASS_MAPPINGS.update({
     "JoyEcho_ModelLoader": JoyEcho_ModelLoader,
+    "JoyEcho_LoraStacker": JoyEcho_LoraStacker,
     "JoyEcho_TextEncode": JoyEcho_TextEncode,
     "JoyEcho_Generate": JoyEcho_Generate,
     "JoyEcho_SingleShotGenerate": JoyEcho_SingleShotGenerate,
@@ -44,6 +46,7 @@ NODE_CLASS_MAPPINGS.update({
 })
 NODE_DISPLAY_NAME_MAPPINGS.update({
     "JoyEcho_ModelLoader": "JoyEcho Model Loader",
+    "JoyEcho_LoraStacker": "JoyEcho LoRA Stack",
     "JoyEcho_TextEncode": "JoyEcho Text Encode",
     "JoyEcho_Generate": "JoyEcho Generate (Multi-Shot)",
     "JoyEcho_SingleShotGenerate": "JoyEcho Single Shot Generate",

nodes.py

@@ -253,6 +253,41 @@ def _resolve_gemma_file(choice: str) -> str:
     return _resolve_cat_file(choice, _GEMMA_FILE_CATS, "gemma_file", _GEMMA_FILE_MANUAL)
 
 
+class JoyEcho_LoraStacker:
+    """Chainable LoRA stack - the familiar dropdown+strength UI. Each node adds
+    up to three LoRAs; wire lora_stack to another stacker to chain more, and
+    the final one into the Model Loader's lora_stack input. Every entry is
+    fused into the DiT at load (safetensors DiT path only)."""
+
+    @classmethod
+    def INPUT_TYPES(cls):
+        lora_list = ["(none)"] + [x for x in _list_lora_files()
+                                  if x != _LORA_FILE_MANUAL]
+        opt = {"lora_stack": ("JOYECHO_LORA_STACK", {
+            "tooltip": "Chain from another LoRA Stack node to add more slots."})}
+        for i in (1, 2, 3):
+            opt[f"lora_{i}"] = (lora_list, {
+                "default": "(none)",
+                "tooltip": "LoRA from models/loras. (none) = slot unused."})
+            opt[f"strength_{i}"] = ("FLOAT", {
+                "default": 1.0, "min": 0.0, "max": 2.0, "step": 0.05})
+        return {"required": {}, "optional": opt}
+
+    RETURN_TYPES = ("JOYECHO_LORA_STACK",)
+    RETURN_NAMES = ("lora_stack",)
+    FUNCTION = "stack"
+    CATEGORY = "JoyAI-Echo"
+
+    def stack(self, lora_stack=None, **kw):
+        out = list(lora_stack) if lora_stack else []
+        for i in (1, 2, 3):
+            choice = kw.get(f"lora_{i}") or "(none)"
+            if choice != "(none)" and ": " in str(choice):
+                out.append((_resolve_lora_file(choice),
+                            float(kw.get(f"strength_{i}", 1.0))))
+        return (out,)
+
+
 class JoyEcho_ModelLoader:
     """Load JoyAI-Echo model components: text encoder, DiT generator, and VAEs."""
 
@@ -306,6 +341,11 @@ class JoyEcho_ModelLoader:
                                "path (ignored when a GGUF DiT is selected). Refresh the node "
                                "list (R) after adding files.",
                 }),
+                "lora_stack": ("JOYECHO_LORA_STACK", {
+                    "tooltip": "Wire a JoyEcho LoRA Stack node here for the "
+                               "dropdown+strength multi-LoRA UI. Stacks with "
+                               "lora_file and lora_path entries.",
+                }),
                 "lora_path": ("STRING", {
                     "default": "",
                     "multiline": True,
@@ -364,6 +404,7 @@ class JoyEcho_ModelLoader:
 
     def load_model(self, checkpoint_path: str = "", gemma_path: str = "",
                    lora_path: str = "", lora_strength: float = 1.0,
+                   lora_stack=None,
                    low_vram: bool = False, fp8_transformer: bool = False,
                    model_file: str = _MODEL_FILE_MANUAL,
                    lora_file: str = _LORA_FILE_MANUAL,
@@ -490,6 +531,8 @@ class JoyEcho_ModelLoader:
         if dropdown_lora:
             _lora_entries.append((dropdown_lora, float(lora_strength)))
         _lora_entries.extend(_parse_lora_entries(lora_path, lora_strength))
+        if lora_stack:
+            _lora_entries.extend((str(p), float(st)) for p, st in lora_stack)
         # dedupe identical paths (dropdown pick repeated in lora_path)
         _seen = set()
         _lora_entries = [e for e in _lora_entries

workflow/JoyEcho_Multishot_Workflow_PUBLIC.json

@@ -1,8 +1,8 @@
 {
   "id": "dabc6ca9-5fa6-414e-9cdd-33077930aa75",
   "revision": 0,
-  "last_node_id": 64,
-  "last_link_id": 118,
+  "last_node_id": 65,
+  "last_link_id": 119,
   "nodes": [
     {
       "id": 2,
@@ -1472,6 +1472,11 @@
             "name": "low_vram"
           },
           "link": null
+        },
+        {
+          "name": "lora_stack",
+          "type": "JOYECHO_LORA_STACK",
+          "link": 119
         }
       ],
       "outputs": [
@@ -1506,6 +1511,50 @@
         false,
         false
       ]
+    },
+    {
+      "id": 65,
+      "type": "JoyEcho_LoraStacker",
+      "pos": [
+        2470.3581267217646,
+        66.94214876033413
+      ],
+      "size": [
+        300,
+        250
+      ],
+      "flags": {},
+      "order": 0,
+      "mode": 0,
+      "inputs": [
+        {
+          "name": "lora_stack",
+          "type": "JOYECHO_LORA_STACK",
+          "link": null
+        }
+      ],
+      "outputs": [
+        {
+          "name": "lora_stack",
+          "type": "JOYECHO_LORA_STACK",
+          "links": [
+            119
+          ],
+          "slot_index": 0
+        }
+      ],
+      "title": "LoRA Stack (pick up to 3; chain for more)",
+      "properties": {
+        "Node name for S&R": "JoyEcho_LoraStacker"
+      },
+      "widgets_values": [
+        "(none)",
+        1.0,
+        "(none)",
+        1.0,
+        "(none)",
+        1.0
+      ]
     }
   ],
   "links": [
@@ -1628,6 +1677,14 @@
       2,
       0,
       "JOYECHO_MODEL"
+    ],
+    [
+      119,
+      65,
+      0,
+      64,
+      11,
+      "JOYECHO_LORA_STACK"
     ]
   ],
   "groups": [