小优化，产品愿景，视觉规范，交互和导航大版本

art-agent/backend/app/services/view_transform.py

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+"""视角变换服务 — 调用 Zero123++ 等模型，将单张图片转为多视角图片。"""
+
+import base64
+import logging
+import mimetypes
+import os
+import uuid
+from pathlib import Path
+from typing import Any
+
+import httpx
+from PIL import Image
+
+from app.config import get_view_transform_model_config
+from app.services.image_gen import _make_replicate_client, GENERATED_DIR, to_data_uri
+
+logger = logging.getLogger(__name__)
+
+_replicate_client = _make_replicate_client()
+
+
+def _split_grid_image(
+    image_path: Path,
+    cols: int,
+    rows: int,
+    view_labels: list[dict[str, int]],
+) -> list[dict[str, Any]]:
+    """将 Zero123++ 输出的 grid 拼接图切分为独立的视角图片。
+
+    返回格式：[{"url": "/generated/xxx.png", "azimuth": 30, "elevation": 30}, ...]
+    Grid 布局从左到右、从上到下依次对应 view_labels 中的视角。
+    """
+    img = Image.open(image_path)
+    w, h = img.size
+    cell_w = w // cols
+    cell_h = h // rows
+
+    results: list[dict[str, Any]] = []
+    for idx, view in enumerate(view_labels):
+        row_idx = idx // cols
+        col_idx = idx % cols
+        left = col_idx * cell_w
+        upper = row_idx * cell_h
+        right = left + cell_w
+        lower = upper + cell_h
+
+        cropped = img.crop((left, upper, right, lower))
+        filename = f"view_{uuid.uuid4().hex[:8]}_az{view['azimuth']}_el{view['elevation']}.png"
+        filepath = GENERATED_DIR / filename
+        cropped.save(filepath, "PNG")
+
+        results.append({
+            "url": f"/generated/{filename}",
+            "azimuth": view["azimuth"],
+            "elevation": view["elevation"],
+        })
+
+    return results
+
+
+async def _download_to_local(url: str) -> Path:
+    """下载远程图片到本地 generated/ 目录，返回本地路径。"""
+    filename = f"grid_{uuid.uuid4().hex}.png"
+    filepath = GENERATED_DIR / filename
+    proxy = os.environ.get("HTTPS_PROXY") or os.environ.get("HTTP_PROXY")
+    async with httpx.AsyncClient(proxy=proxy, timeout=httpx.Timeout(120.0)) as client:
+        resp = await client.get(url, follow_redirects=True)
+        resp.raise_for_status()
+        filepath.write_bytes(resp.content)
+    return filepath
+
+
+async def transform_view(
+    image_path: str,
+    model_id: str | None = None,
+) -> dict[str, Any]:
+    """调用视角变换模型，返回多视角图片列表。
+
+    Args:
+        image_path: 输入图片路径（本地路径、data URI 或 URL）
+        model_id: 视角变换模型 ID，默认 zero123plus
+
+    Returns:
+        {
+            "success": bool,
+            "images": [{"url": str, "azimuth": int, "elevation": int}, ...],
+            "grid_image": str,  # 原始拼接图的本地 URL
+            "model_name": str,
+            "error": str | None,
+        }
+    """
+    config = get_view_transform_model_config(model_id)
+    model_name = config["name"]
+    replicate_model_id = config["model_id"]
+    grid_layout = config["grid_layout"]
+    output_views = config["output_views"]
+
+    GENERATED_DIR.mkdir(parents=True, exist_ok=True)
+
+    try:
+        image_uri = to_data_uri(image_path)
+        input_params = {"image": image_uri}
+
+        logger.info("调用 %s 进行视角变换...", model_name)
+        output = await _replicate_client.async_run(
+            replicate_model_id, input=input_params, wait=False
+        )
+
+        # Zero123++ 返回单张 grid 拼接图
+        items = output if isinstance(output, list) else [output]
+        if not items:
+            return {
+                "success": False,
+                "images": [],
+                "grid_image": None,
+                "model_name": model_name,
+                "error": "模型未返回任何输出",
+            }
+
+        grid_url = str(items[0])
+        if not (grid_url.startswith("http://") or grid_url.startswith("https://")):
+            return {
+                "success": False,
+                "images": [],
+                "grid_image": None,
+                "model_name": model_name,
+                "error": f"模型返回非图片内容: {grid_url[:200]}",
+            }
+
+        grid_local_path = await _download_to_local(grid_url)
+        grid_local_url = f"/generated/{grid_local_path.name}"
+
+        view_images = _split_grid_image(
+            grid_local_path,
+            cols=grid_layout["cols"],
+            rows=grid_layout["rows"],
+            view_labels=output_views,
+        )
+
+        return {
+            "success": True,
+            "images": view_images,
+            "grid_image": grid_local_url,
+            "model_name": model_name,
+            "error": None,
+        }
+
+    except Exception as e:
+        detail = str(e) or f"{type(e).__name__}: {repr(e)}"
+        logger.error("视角变换失败: %s", detail, exc_info=True)
+        return {
+            "success": False,
+            "images": [],
+            "grid_image": None,
+            "model_name": model_name,
+            "error": detail,
+        }