fix algining xynova texture to uv printing fixture.

tests/test_texture_views.py

@@ -430,6 +430,105 @@ def test_real_revisions_declare_the_seam_margin(real_revision: Path) -> None:
     assert gap["total_mm"] == pytest.approx(0.2)
 
 
+# ---------------------------------------------------------------- page sizing
+
+
+def test_page_defaults_to_auto_at_the_shipped_density(tmp_path: Path) -> None:
+    revision = _write_revision(tmp_path, TWO_PAIRS)
+    paths = RevisionPaths.from_revision_dir(revision)
+    page = texture_views.resolve_page_settings(texture_views.load_views_block(paths))
+    assert page == {"mode": "auto", "px_per_mm": 200.0}
+
+
+def test_page_density_reproduces_the_existing_rasters() -> None:
+    """200 px/mm is what both revisions already use exactly, so only the proportion changes."""
+    assert texture_views.PAGE_DEFAULT_PX_PER_MM == 200.0
+    for raster, page_mm in ((3280, 16.4), (3200, 16.0), (3700, 18.5)):
+        assert raster / page_mm == pytest.approx(200.0)
+
+
+def test_page_fixed_keeps_the_texture_patch_page(tmp_path: Path) -> None:
+    revision = _write_revision(tmp_path, TWO_PAIRS + "  page:\n    mode: fixed\n")
+    paths = RevisionPaths.from_revision_dir(revision)
+    settings = resolve_texture_settings(paths)
+    block = texture_views.load_views_block(paths)
+    pairs = texture_views.resolve_view_pairs(paths, settings, block)
+    job = texture_views.build_multiview_job(paths, settings, pairs, tmp_path / "o", block)
+    assert job["page"]["mode"] == "fixed"
+    assert all(pair["page"] == "fixed" for pair in job["pairs"])
+
+
+def test_per_pair_page_override_wins(tmp_path: Path) -> None:
+    revision = _write_revision(tmp_path, _block(
+        "    - id: uv_1\n      camera: cam_uv_1\n      uv_map: uv_1\n      page: fixed\n"
+        "    - id: uv_2\n      camera: cam_uv_2\n      uv_map: uv_2\n",
+    ) + "  page:\n    mode: auto\n")
+    paths = RevisionPaths.from_revision_dir(revision)
+    settings = resolve_texture_settings(paths)
+    block = texture_views.load_views_block(paths)
+    pairs = texture_views.resolve_view_pairs(paths, settings, block)
+    assert [pair.page_mode for pair in pairs] == ["fixed", "auto"]
+
+
+@pytest.mark.parametrize(
+    ("page_yaml", "expected"),
+    [
+        ("  page:\n    mode: guessed\n", "mode"),
+        ("  page:\n    px_per_mm: 0\n", "px_per_mm"),
+        ("  page:\n    px_per_mm: -5\n", "px_per_mm"),
+        ("  page:\n    px_per_mm: thick\n", "px_per_mm"),
+        ("  page:\n    nope: 1\n", "unknown key"),
+        ("  page: nope\n", "must be a mapping"),
+        (
+            "  pairs:\n    - {id: a, camera: c, uv_map: u, page: sideways}\n",
+            "page",
+        ),
+    ],
+)
+def test_page_block_rejects_bad_values(tmp_path: Path, page_yaml: str, expected: str) -> None:
+    if page_yaml.startswith("  pairs:"):
+        # This case replaces the pairs block rather than appending to it.
+        revision = _write_revision(
+            tmp_path,
+            "texture_patch_views:\n  enabled: true\n" + page_yaml,
+        )
+    else:
+        revision = _write_revision(tmp_path, TWO_PAIRS + page_yaml)
+    paths = RevisionPaths.from_revision_dir(revision)
+    with pytest.raises(TextureConfigError) as excinfo:
+        texture_views.resolve_view_pairs(paths, resolve_texture_settings(paths))
+    assert expected in str(excinfo.value)
+
+
+def test_real_revisions_size_the_page_per_view(real_revision: Path) -> None:
+    """Both shipped revisions derive the page, at the density that preserves their raster."""
+    paths = RevisionPaths.from_revision_dir(real_revision)
+    block = texture_views.load_views_block(paths)
+    page = texture_views.resolve_page_settings(block)
+    assert page["mode"] == "auto"
+    assert page["px_per_mm"] == 200.0
+    assert all(pair.page_mode == "auto" for pair in texture_views.resolve_view_pairs(
+        paths, resolve_texture_settings(paths), block
+    ))
+
+
+def test_page_derivation_is_not_attempted_host_side(real_revision: Path) -> None:
+    """The page needs the mesh and the camera, so the host carries the mode, not a number.
+
+    If the host ever starts printing a page it computed itself, this fails — which is the
+    point: the console must describe the page the run used, not one it guessed.
+    """
+    paths = RevisionPaths.from_revision_dir(real_revision)
+    block = texture_views.load_views_block(paths)
+    settings = resolve_texture_settings(paths)
+    pairs = texture_views.resolve_view_pairs(paths, settings, block)
+    job = texture_views.build_multiview_job(paths, settings, pairs, paths.root / "o", block)
+    assert "page_mm" not in job
+    assert isinstance(job["page"]["mode"], str)
+    for pair in job["pairs"]:
+        assert pair["page"] in texture_views.PAGE_MODES
+
+
 def test_authored_merge_block_resolves_into_the_job(tmp_path: Path) -> None:
     revision = _write_revision(tmp_path, TWO_PAIRS + AUTHORED_MERGE)
     paths = RevisionPaths.from_revision_dir(revision)