ModelTranslator: add QR bridge pure logic

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Tools/ModelTranslator/qr_bridge.py

@@ -0,0 +1,63 @@
+"""QR 桥纯逻辑：引擎发现、面数换算、settings 生成、progress 解析。不 import bpy。
+减面可选后端 Quad Remesher 用——headless 直接调 Engine/xremesh.exe，绕开 modal 操作符。"""
+import glob
+import os
+
+QR_TIMEOUT = 120.0   # 引擎轮询超时（秒）
+
+
+def find_qr_engine():
+    """定位 QuadRemesher 的 xremesh.exe；找不到返回 None。
+    顺序：QR_ENGINE 环境变量 -> 标准 addon 路径（取最高 Blender 版本目录）。"""
+    env = os.environ.get("QR_ENGINE")
+    if env and os.path.isfile(env):
+        return env
+    appdata = os.environ.get("APPDATA")
+    if not appdata:
+        return None
+    pattern = os.path.join(
+        appdata, "Blender Foundation", "Blender", "*",
+        "scripts", "addons", "QuadRemesher", "Engine", "xremesh.exe")
+    hits = sorted(glob.glob(pattern))
+    return hits[-1] if hits else None
+
+
+def tris_to_target_quads(tris):
+    """三角面数换算 QR 目标四边形数：1 quad ≈ 2 tris，至少 1。"""
+    return max(1, int(tris) // 2)
+
+
+def build_settings(in_fbx, out_fbx, prog, target_quads,
+                   adaptive=50, exact=False, hard_edges=True):
+    """生成 RetopoSettings.txt 文本（xremesh.exe -s 读取）。"""
+    lines = [
+        "HostApp=Blender",
+        'FileIn="%s"' % in_fbx,
+        'FileOut="%s"' % out_fbx,
+        'ProgressFile="%s"' % prog,
+        "TargetQuadCount=%d" % target_quads,
+        "CurvatureAdaptivness=%d" % adaptive,
+        "ExactQuadCount=%d" % (1 if exact else 0),
+        "UseVertexColorMap=False",
+        "UseMaterialIds=0",
+        "UseIndexedNormals=0",
+        "AutoDetectHardEdges=%d" % (1 if hard_edges else 0),
+    ]
+    return "\n".join(lines) + "\n"
+
+
+def parse_progress(text):
+    """解析 progress.txt -> (state, msg)。
+    首行 '2'=success；<0=error（次行为文本）；空/分数/非法=running。"""
+    lines = text.splitlines()
+    if not lines:
+        return ("running", "")
+    try:
+        v = float(lines[0])
+    except ValueError:
+        return ("running", "")
+    if v == 2:
+        return ("success", "")
+    if v < 0:
+        return ("error", lines[1] if len(lines) > 1 else "")
+    return ("running", "")

Tools/ModelTranslator/tests/test_qr_bridge.py

@@ -0,0 +1,88 @@
+import os
+import sys
+import tempfile
+import unittest
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+import qr_bridge as qb
+
+
+class TestTrisToTargetQuads(unittest.TestCase):
+    def test_half(self):
+        self.assertEqual(qb.tris_to_target_quads(10000), 5000)
+
+    def test_odd_floors(self):
+        self.assertEqual(qb.tris_to_target_quads(3), 1)
+
+    def test_at_least_one(self):
+        self.assertEqual(qb.tris_to_target_quads(1), 1)
+        self.assertEqual(qb.tris_to_target_quads(0), 1)
+
+
+class TestBuildSettings(unittest.TestCase):
+    def _s(self, **kw):
+        return qb.build_settings("/i.fbx", "/o.fbx", "/p.txt", 500, **kw)
+
+    def test_core_lines_present(self):
+        s = self._s()
+        self.assertIn('FileIn="/i.fbx"', s)
+        self.assertIn('FileOut="/o.fbx"', s)
+        self.assertIn('ProgressFile="/p.txt"', s)
+        self.assertIn("TargetQuadCount=500", s)
+        self.assertIn("HostApp=Blender", s)
+        self.assertTrue(s.endswith("\n"))
+
+    def test_hard_edges_toggle(self):
+        self.assertIn("AutoDetectHardEdges=1", self._s(hard_edges=True))
+        self.assertIn("AutoDetectHardEdges=0", self._s(hard_edges=False))
+
+    def test_exact_toggle(self):
+        self.assertIn("ExactQuadCount=0", self._s(exact=False))
+        self.assertIn("ExactQuadCount=1", self._s(exact=True))
+
+
+class TestParseProgress(unittest.TestCase):
+    def test_success(self):
+        self.assertEqual(qb.parse_progress("2\n"), ("success", ""))
+
+    def test_error_with_text(self):
+        self.assertEqual(qb.parse_progress("-3\n重拓扑失败"), ("error", "重拓扑失败"))
+
+    def test_error_no_text(self):
+        self.assertEqual(qb.parse_progress("-3"), ("error", ""))
+
+    def test_running_fraction(self):
+        self.assertEqual(qb.parse_progress("0.5"), ("running", ""))
+
+    def test_running_empty(self):
+        self.assertEqual(qb.parse_progress(""), ("running", ""))
+
+    def test_running_garbage(self):
+        self.assertEqual(qb.parse_progress("abc"), ("running", ""))
+
+
+class TestFindQrEngine(unittest.TestCase):
+    def setUp(self):
+        self._env = dict(os.environ)
+
+    def tearDown(self):
+        os.environ.clear()
+        os.environ.update(self._env)
+
+    def test_env_var_priority(self):
+        with tempfile.NamedTemporaryFile(suffix=".exe", delete=False) as f:
+            path = f.name
+        try:
+            os.environ["QR_ENGINE"] = path
+            self.assertEqual(qb.find_qr_engine(), path)
+        finally:
+            os.remove(path)
+
+    def test_missing_returns_none(self):
+        os.environ["QR_ENGINE"] = os.path.join(tempfile.gettempdir(), "nope_xremesh.exe")
+        os.environ["APPDATA"] = tempfile.mkdtemp()
+        self.assertIsNone(qb.find_qr_engine())
+
+
+if __name__ == "__main__":
+    unittest.main()