lightningpixel · lightningpixel · Apr 9, 2026 · Apr 9, 2026
diff --git a/api/runner.py b/api/runner.py
@@ -109,8 +109,16 @@ def main() -> None:
     send({"type": "ready", "params_schema": schema})
 
     # Support both flat manifest (legacy) and nodes[] format.
-    # Node-level fields take precedence; fall back to top-level for compatibility.
-    node = (manifest.get("nodes") or [{}])[0]
+    # Use MODEL_DIR to find the correct node for multi-node extensions:
+    # MODEL_DIR is set by ExtensionProcess to MODELS_DIR/ext_id/node_id,
+    # so its last component matches the node id.
+    nodes = manifest.get("nodes") or []
+    node = {}
+    if nodes and _MODEL_DIR_OVERRIDE:
+        node_id = Path(_MODEL_DIR_OVERRIDE).name
+        node = next((n for n in nodes if n.get("id") == node_id), nodes[0])
+    elif nodes:
+        node = nodes[0]
 
     # Use MODEL_DIR env var (set by ExtensionProcess) when available so the
     # generator uses the exact same path that is_downloaded() checks against.

diff --git a/api/services/generator_registry.py b/api/services/generator_registry.py
@@ -227,11 +227,12 @@ def get_active(self) -> BaseGenerator:
         if not gen.is_loaded():
             if not gen.is_downloaded():
                 if isinstance(gen, ExtensionProcess):
-                    raise RuntimeError(
-                        f"Model '{self._active_id}' is not downloaded. "
-                        "Please install it from the Models page first."
-                    )
-                gen._auto_download()
+                    # Let the subprocess handle its own download logic during
+                    # load() — some extensions (e.g. mv-adapter) need custom
+                    # multi-repo downloads that the standard HF endpoint can't do.
+                    pass
+                else:
+                    gen._auto_download()
             gen.load()
         return gen
 

diff --git a/electron/main/ipc-handlers.ts b/electron/main/ipc-handlers.ts
@@ -510,6 +510,7 @@ export function setupIpcHandlers(pythonBridge: PythonBridge, getWindow: WindowGe
       id:                string
       name?:             string
       input?:            'mesh' | 'image' | 'text'
+      inputs?:           ('mesh' | 'image' | 'text')[]
       output?:           'mesh' | 'image' | 'text'
       params_schema?:    unknown[]
       hf_repo?:          string
@@ -534,6 +535,7 @@ export function setupIpcHandlers(pythonBridge: PythonBridge, getWindow: WindowGe
       id:             n.id,
       name:           n.name ?? n.id,
       input:          n.input  ?? 'image' as const,
+      inputs:         n.inputs,
       output:         n.output ?? 'mesh'  as const,
       paramsSchema:   n.params_schema ?? [],
       hfRepo:         n.hf_repo,

diff --git a/src/areas/generate/components/WorkflowPanel.tsx b/src/areas/generate/components/WorkflowPanel.tsx
@@ -420,20 +420,30 @@ function EmbeddedCanvas({ workflow, allExtensions }: {
     if (out) updateNodeData(out.id, { params: { outputUrl: runState.outputUrl } })
   }, [runState.status, runState.outputUrl])
 
-  // Type mismatch detection
+  // Type mismatch detection — edge-based to support multi-input nodes
   const typeMismatch = useMemo(() => {
-    const sorted   = topoSortNodes(workflow.nodes, workflow.edges)
-    const extNodes = sorted.filter((n) => n.type === 'extensionNode')
-    // Determine initial type from the actual source node in the graph
-    const firstSource = sorted.find((n) => n.type === 'imageNode' || n.type === 'meshNode' || n.type === 'textNode')
-    let prev: string = firstSource?.type === 'meshNode' ? 'mesh'
-                     : firstSource?.type === 'textNode' ? 'text'
-                     : 'image'
+    // Build a map of what type each node produces
+    const nodeOutput = new Map<string, string>()
+    for (const node of workflow.nodes) {
+      if (node.type === 'imageNode')  { nodeOutput.set(node.id, 'image'); continue }
+      if (node.type === 'meshNode')   { nodeOutput.set(node.id, 'mesh');  continue }
+      if (node.type === 'textNode')   { nodeOutput.set(node.id, 'text');  continue }
+      if (node.type === 'extensionNode') {
+        const ext = getWorkflowExtension(node.data.extensionId ?? '', allExtensions)
+        if (ext) nodeOutput.set(node.id, ext.output)
+      }
+    }
+    // For each extension node, check that every incoming edge carries an accepted type
+    const extNodes = workflow.nodes.filter((n) => n.type === 'extensionNode')
     for (const node of extNodes) {
       const ext = getWorkflowExtension(node.data.extensionId ?? '', allExtensions)
       if (!ext) continue
-      if (prev !== ext.input) return true
-      prev = ext.output
+      const accepted = ext.inputs ?? [ext.input]
+      for (const edge of workflow.edges) {
+        if (edge.target !== node.id) continue
+        const srcType = nodeOutput.get(edge.source)
+        if (srcType && !accepted.includes(srcType as any)) return true
+      }
     }
     return false
   }, [workflow, allExtensions])

diff --git a/src/areas/workflows/WorkflowsPage.tsx b/src/areas/workflows/WorkflowsPage.tsx
@@ -21,18 +21,19 @@ import type { Workflow, WFNode, WFEdge, WFNodeData } from '@shared/types/electro
 import { buildAllWorkflowExtensions, getWorkflowExtension } from './mockExtensions'
 import type { WorkflowExtension } from './mockExtensions'
 import { useWorkflowRunStore } from './workflowRunStore'
-import ExtensionNode   from './nodes/ExtensionNode'
-import ImageNode       from './nodes/ImageNode'
-import TextNode        from './nodes/TextNode'
-import AddToSceneNode  from './nodes/AddToSceneNode'
-import Load3DMeshNode  from './nodes/Load3DMeshNode'
-import WorkflowEdge    from './nodes/WorkflowEdge'
+import ExtensionNode    from './nodes/ExtensionNode'
+import ImageNode        from './nodes/ImageNode'
+import TextNode         from './nodes/TextNode'
+import AddToSceneNode   from './nodes/AddToSceneNode'
+import Load3DMeshNode   from './nodes/Load3DMeshNode'
+import PreviewImageNode from './nodes/PreviewImageNode'
+import WorkflowEdge     from './nodes/WorkflowEdge'
 
 // ─── Constants ────────────────────────────────────────────────────────────────
 
 const DRAG_KEY      = 'modly/extension-id'
 const DRAG_NODE_KEY = 'modly/node-type'
-const NODE_TYPES = { extensionNode: ExtensionNode, imageNode: ImageNode, textNode: TextNode, outputNode: AddToSceneNode, meshNode: Load3DMeshNode }
+const NODE_TYPES = { extensionNode: ExtensionNode, imageNode: ImageNode, textNode: TextNode, outputNode: AddToSceneNode, meshNode: Load3DMeshNode, previewNode: PreviewImageNode }
 const EDGE_TYPES = { workflowEdge: WorkflowEdge }
 
 const DEFAULT_EDGE_OPTS = { type: 'workflowEdge' }
@@ -149,10 +150,11 @@ const PANEL_MIN = 240
 const PANEL_MAX = 860
 
 const PANEL_BUILTIN_NODES = [
-  { type: 'imageNode',  label: 'Image',        color: '#38bdf8', icon: <><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="8.5" cy="8.5" r="1.5"/><polyline points="21 15 16 10 5 21"/></> },
-  { type: 'textNode',   label: 'Text',          color: '#fbbf24', icon: <><path d="M17 6.1H3M21 12.1H3M15.1 18H3"/></> },
-  { type: 'meshNode',   label: 'Load 3D Mesh',  color: '#a78bfa', icon: <><path d="M12 2L2 7l10 5 10-5-10-5zM2 17l10 5 10-5M2 12l10 5 10-5"/></> },
-  { type: 'outputNode', label: 'Add to Scene',  color: '#a78bfa', icon: <><path d="M21 16V8a2 2 0 0 0-1-1.73l-7-4a2 2 0 0 0-2 0l-7 4A2 2 0 0 0 3 8v8a2 2 0 0 0 1 1.73l7 4a2 2 0 0 0 2 0l7-4A2 2 0 0 0 21 16z"/></> },
+  { type: 'imageNode',   label: 'Image',         color: '#38bdf8', icon: <><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="8.5" cy="8.5" r="1.5"/><polyline points="21 15 16 10 5 21"/></> },
+  { type: 'textNode',    label: 'Text',           color: '#fbbf24', icon: <><path d="M17 6.1H3M21 12.1H3M15.1 18H3"/></> },
+  { type: 'meshNode',    label: 'Load 3D Mesh',   color: '#a78bfa', icon: <><path d="M12 2L2 7l10 5 10-5-10-5zM2 17l10 5 10-5M2 12l10 5 10-5"/></> },
+  { type: 'outputNode',  label: 'Add to Scene',   color: '#a78bfa', icon: <><path d="M21 16V8a2 2 0 0 0-1-1.73l-7-4a2 2 0 0 0-2 0l-7 4A2 2 0 0 0 3 8v8a2 2 0 0 0 1 1.73l7 4a2 2 0 0 0 2 0l7-4A2 2 0 0 0 21 16z"/></> },
+  { type: 'previewNode', label: 'Preview Views',  color: '#38bdf8', icon: <><rect x="3" y="3" width="8" height="8" rx="1"/><rect x="13" y="3" width="8" height="8" rx="1"/><rect x="3" y="13" width="8" height="8" rx="1"/><rect x="13" y="13" width="8" height="8" rx="1"/></> },
 ]
 
 function ExtGroupHeader({ title, author, expanded, onToggle, count }: { title: string; author?: string; expanded: boolean; onToggle: () => void; count: number }) {
@@ -391,10 +393,11 @@ function PanelToggleIcon({ open }: { open: boolean }) {
 // ─── Node palette (Space to open) ────────────────────────────────────────────
 
 const BUILTIN_NODES = [
-  { type: 'imageNode',  label: 'Image',        color: '#38bdf8', description: 'Image input' },
-  { type: 'textNode',   label: 'Text',          color: '#fbbf24', description: 'Text input' },
-  { type: 'meshNode',   label: 'Load 3D Mesh',  color: '#a78bfa', description: 'Load a 3D mesh file or use current model' },
-  { type: 'outputNode', label: 'Add to Scene',  color: '#a78bfa', description: 'Output node' },
+  { type: 'imageNode',   label: 'Image',         color: '#38bdf8', description: 'Image input' },
+  { type: 'textNode',    label: 'Text',           color: '#fbbf24', description: 'Text input' },
+  { type: 'meshNode',    label: 'Load 3D Mesh',   color: '#a78bfa', description: 'Load a 3D mesh file or use current model' },
+  { type: 'outputNode',  label: 'Add to Scene',   color: '#a78bfa', description: 'Output node — adds the mesh to the 3D scene' },
+  { type: 'previewNode', label: 'Preview Views',  color: '#38bdf8', description: 'Displays multi-view image outputs in a 2×3 grid' },
 ]
 
 type PaletteItem =
@@ -732,6 +735,32 @@ function HelpModal({ onClose }: { onClose: () => void }) {
   )
 }
 
+// ─── Connection type helpers ──────────────────────────────────────────────────
+
+function getNodeOutputType(node: Node | undefined, allExts: WorkflowExtension[]): string | undefined {
+  if (!node) return undefined
+  if (node.type === 'imageNode') return 'image'
+  if (node.type === 'meshNode')  return 'mesh'
+  if (node.type === 'textNode')  return 'text'
+  return allExts.find((e) => e.id === (node.data as WFNodeData)?.extensionId)?.output
+}
+
+function getNodeInputType(
+  node: Node | undefined,
+  targetHandle: string | null | undefined,
+  allExts: WorkflowExtension[],
+): string | undefined {
+  if (!node) return undefined
+  if (node.type === 'outputNode')  return 'mesh'
+  if (node.type === 'previewNode') return 'image'
+  const ext = allExts.find((e) => e.id === (node.data as WFNodeData)?.extensionId)
+  if (ext?.inputs && ext.inputs.length > 1 && targetHandle) {
+    const idx = parseInt(targetHandle.replace('input-', ''), 10)
+    return ext.inputs[isNaN(idx) ? 0 : idx] ?? ext.input
+  }
+  return ext?.input
+}
+
 // ─── Workflow canvas (inner, requires ReactFlowProvider) ──────────────────────
 
 function WorkflowCanvasInner({
@@ -747,7 +776,7 @@ function WorkflowCanvasInner({
   onNew:            () => void
   onImport:         () => void
 }) {
-  const { screenToFlowPosition, updateNodeData } = useReactFlow()
+  const { screenToFlowPosition, updateNodeData, getNode } = useReactFlow()
   const { runState, run: runWorkflow, cancel } = useWorkflowRunStore()
   const isRunning = runState.status === 'running'
 
@@ -838,6 +867,13 @@ function WorkflowCanvasInner({
   const canUndo = histIdx > 0
   const canRedo = histIdx < historyRef.current.length - 1
 
+  const isValidConnection = useCallback((connection: Connection) => {
+    const srcType = getNodeOutputType(getNode(connection.source) as Node, allExtensions)
+    const tgtType = getNodeInputType(getNode(connection.target) as Node, connection.targetHandle, allExtensions)
+    if (!srcType || !tgtType) return true  // unknown type — allow
+    return srcType === tgtType
+  }, [getNode, allExtensions])
+
   const onConnectStart = useCallback((_: React.MouseEvent | React.TouchEvent, params: OnConnectStartParams) => {
     pendingConnectionRef.current  = params
     connectionCompletedRef.current = false
@@ -1133,6 +1169,7 @@ function WorkflowCanvasInner({
           onEdgesChange={onEdgesChange}
           onConnectStart={onConnectStart}
           onConnect={onConnect}
+          isValidConnection={isValidConnection}
           onConnectEnd={onConnectEnd}
           onEdgeContextMenu={(e, edge) => { e.preventDefault(); setEdges((eds) => eds.filter((ed) => ed.id !== edge.id)) }}
           defaultEdgeOptions={DEFAULT_EDGE_OPTS}

diff --git a/src/areas/workflows/mockExtensions.ts b/src/areas/workflows/mockExtensions.ts
@@ -11,6 +11,7 @@ export interface WorkflowExtension {
   name:            string
   description:     string
   input:           'image' | 'text' | 'mesh'
+  inputs?:         ('image' | 'text' | 'mesh')[]   // multi-input; overrides input when set
   output:          'image' | 'text' | 'mesh'
   params:          ParamSchema[]
   builtin:         boolean
@@ -34,6 +35,7 @@ export function buildAllWorkflowExtensions(
         name:            node.name,
         description:     ext.description ?? '',
         input:           node.input,
+        inputs:          node.inputs,
         output:          node.output,
         params:          node.paramsSchema as ParamSchema[],
         builtin:         ext.builtin,
@@ -53,6 +55,7 @@ export function buildAllWorkflowExtensions(
         name:            node.name,
         description:     ext.description ?? '',
         input:           node.input,
+        inputs:          node.inputs,
         output:          node.output,
         params:          node.paramsSchema as ParamSchema[],
         builtin:         ext.builtin,