Fix viewer not updating: direct GLB output + allowed_paths

- Moved gen_btn.click() wiring to after gr.Model3D viewer is defined
so outputs=[gen_status, viewer] is valid (viewer was not in scope
when the click was wired inside Tab 1)
- generate_hunyuan() now yields (status_str, glb_path|None) tuples;
the final yield carries str(raw_gen_path) so Gradio receives the GLB
path as a direct function output and serves it automatically — no
separate state lookup needed
- Added allowed_paths=[workspace.WORKSPACE] to launch() so Gradio 5
can serve files from the workspace directory (without this, local
paths returned to gr.Model3D are silently rejected)
- _gen_event.then() now only refreshes [summary, status_bar] since the
viewer is already updated by the direct output above
- pp/rig/ex still use _global_refresh for all three (viewer, summary,
status_bar) via .then()

app.py

@@ -82,10 +82,17 @@ def _stub(stage: str) -> str:
 
 
 def handle_generate(images, model, quality, seed, _steps, _octree, tex_size, _symmetry, do_rembg):
-    """Dispatch to the correct generation backend. Yields status strings for streaming."""
+    """Dispatch to the correct generation backend.
+
+    Yields (status_markdown, viewer_path_or_None) tuples for streaming.
+    The viewer path is yielded only in the final tuple so Gradio can serve
+    the GLB directly without a separate state lookup.
+    """
     if "TRELLIS" in model:
-        yield f"⚙️ **TRELLIS.2** · {quality}\n\nContacting remote Space..."
-        yield generate_trellis(images, quality, int(seed), int(tex_size))
+        yield f"⚙️ **TRELLIS.2** · {quality}\n\nContacting remote Space...", None
+        result = generate_trellis(images, quality, int(seed), int(tex_size))
+        viewer_path = ui_helpers.get_viewer_model_path()
+        yield result, viewer_path
         return
     yield from generate_hunyuan(images, quality, int(seed), int(tex_size), do_rembg=bool(do_rembg))
 
@@ -466,13 +473,7 @@ def build_ui() -> gr.Blocks:
                         gen_btn = gr.Button("Generate", variant="primary")
                     with gr.Column(scale=1):
                         gen_status = gr.Markdown("*Awaiting input.*")
-                _gen_event = gen_btn.click(
-                    fn=handle_generate,
-                    inputs=[gen_images, gen_model, gen_quality, gen_seed,
-                            gen_steps, gen_octree, gen_tex_size, gen_symmetry,
-                            gen_rembg],
-                    outputs=gen_status,
-                )
+                # Click wired below, after viewer component is defined.
 
             # ============ Tab 2: Post-Process =============================
             with gr.Tab("2. Post-Process", id=2):
@@ -713,10 +714,22 @@ def build_ui() -> gr.Blocks:
             elem_classes=["status-bar"],
         )
 
-        # --- Global refresh: every pipeline action updates the viewer, summary,
-        # and status bar. We chain .then() onto each button so the refresh runs
-        # only after the action completes (and even if it fails — Gradio still
-        # fires .then() after exceptions inside the main handler).
+        # --- Wire generate button now that viewer is in scope ---------------
+        # handle_generate yields (status_str, glb_path_or_None) tuples so that
+        # the viewer updates the instant the final mesh is ready — no separate
+        # state lookup needed.
+        _gen_event = gen_btn.click(
+            fn=handle_generate,
+            inputs=[gen_images, gen_model, gen_quality, gen_seed,
+                    gen_steps, gen_octree, gen_tex_size, gen_symmetry,
+                    gen_rembg],
+            outputs=[gen_status, viewer],
+        )
+
+        # --- Global refresh: every pipeline action updates summary + status bar.
+        # For gen_btn the viewer is already updated directly above; for the rest
+        # we include the viewer in _global_refresh so post-process / rig / export
+        # results also appear.
         def _global_refresh():
             return (
                 ui_helpers.get_viewer_model_path(),
@@ -724,9 +737,14 @@ def build_ui() -> gr.Blocks:
                 ui_helpers.get_status_bar(),
             )
 
-        # Processing buttons: refresh AFTER the operation completes (.then),
-        # not simultaneously with it (.click).
-        for _ev in (_gen_event, _pp_event, _rig_event, _ex_event):
+        def _summary_refresh():
+            return ui_helpers.get_asset_summary(), ui_helpers.get_status_bar()
+
+        # gen_btn: viewer already updated by direct output; only refresh metadata.
+        _gen_event.then(fn=_summary_refresh, outputs=[summary, status_bar])
+
+        # Other processing buttons: refresh viewer + metadata after completion.
+        for _ev in (_pp_event, _rig_event, _ex_event):
             _ev.then(fn=_global_refresh, outputs=[viewer, summary, status_bar])
 
         # Utility buttons: refresh immediately on click.
@@ -749,8 +767,10 @@ demo.queue(default_concurrency_limit=1).launch(
     server_name="0.0.0.0",
     server_port=7860,
     show_error=True,
+    # Allow Gradio to serve files from the workspace directory so that
+    # gr.Model3D can display generated GLBs without a 403 error.
+    allowed_paths=[str(workspace.WORKSPACE)],
     # Gradio 6: show_api removed. Use footer_links instead.
-    # Equivalent of old show_api=False:
     footer_links=["gradio", "settings"],
     theme=gr.themes.Soft(primary_hue="indigo", neutral_hue="slate"),
     css=CUSTOM_CSS,

src/stages/stage1_generate.py

@@ -247,13 +247,13 @@ def generate_hunyuan(
     hdr = f"⚙️ **Hunyuan3D-2.1** · {quality}\n\n"
 
     if not images:
-        yield "❌ Please upload at least one reference image."
+        yield "❌ Please upload at least one reference image.", None
         return
 
     # ------------------------------------------------------------------
     # Step 1 — Load images
     # ------------------------------------------------------------------
-    yield hdr + "**[1/5]** Loading images..."
+    yield hdr + "**[1/5]** Loading images...", None
 
     def _open(f) -> Image.Image:
         path = f.name if hasattr(f, "name") else str(f)
@@ -265,14 +265,14 @@ def generate_hunyuan(
     # Step 2 — Background removal
     # ------------------------------------------------------------------
     if do_rembg:
-        yield hdr + f"**[2/5]** Removing background ({len(pil_images)} image(s))..."
+        yield hdr + f"**[2/5]** Removing background ({len(pil_images)} image(s))...", None
         try:
             pil_images = [_remove_background(img) for img in pil_images]
         except Exception as e:
-            yield f"❌ Background removal failed:\n```\n{e}\n```"
+            yield f"❌ Background removal failed:\n```\n{e}\n```", None
             return
     else:
-        yield hdr + "**[2/5]** Background removal skipped."
+        yield hdr + "**[2/5]** Background removal skipped.", None
 
     preset = _HY_PRESETS.get(quality, _HY_PRESETS["Balanced (~60s)"])
 
@@ -285,12 +285,12 @@ def generate_hunyuan(
     # ------------------------------------------------------------------
     # Step 3 — Load pipeline
     # ------------------------------------------------------------------
-    yield hdr + "**[3/5]** Loading pipeline (first run downloads ~4 GB of weights)..."
+    yield hdr + "**[3/5]** Loading pipeline (first run downloads ~7 GB of weights)...", None
 
     try:
         pipeline = _get_hy_pipeline()
     except Exception as e:
-        yield f"❌ Pipeline load failed:\n```\n{type(e).__name__}: {e}\n```"
+        yield f"❌ Pipeline load failed:\n```\n{type(e).__name__}: {e}\n```", None
         return
 
     # ------------------------------------------------------------------
@@ -298,7 +298,7 @@ def generate_hunyuan(
     # ------------------------------------------------------------------
     steps = preset["steps"]
     octree = preset["octree_resolution"]
-    yield hdr + f"**[4/5]** Generating shape — {steps} diffusion steps, octree {octree}..."
+    yield hdr + f"**[4/5]** Generating shape — {steps} diffusion steps, octree {octree}...", None
 
     # Track step count via callback so we can update progress.
     _progress: list[int] = [0]
@@ -323,13 +323,13 @@ def generate_hunyuan(
         yield (
             f"❌ Hunyuan3D-2.1 generation failed:\n```\n{type(e).__name__}: {e}\n```\n\n"
             f"Tip: make sure the image has a clean subject on a white/transparent background."
-        )
+        ), None
         return
 
     # ------------------------------------------------------------------
     # Step 5 — Save & decimate
     # ------------------------------------------------------------------
-    yield hdr + "**[5/5]** Saving mesh and building working copy..."
+    yield hdr + "**[5/5]** Saving mesh and building working copy...", None
 
     workspace.reset_current()
     ws = workspace.reset_state()
@@ -378,6 +378,5 @@ def generate_hunyuan(
         f"✅ **Generated with Hunyuan3D-2.1** · {quality}\n\n"
         f"- Faces: {face_count:,} · Vertices: {vertex_count:,}\n"
         f"- Time: {elapsed:.1f}s\n\n"
-        f"Scroll down to see the result in the 3D viewer. "
         f"High-poly saved for Stage 2 baking."
-    )
+    ), str(raw_gen_path)