Govern task context and advance execution pointer

tools/web/check-light-desktop.py

@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+import hashlib
+import json
+import os
+import pathlib
+import sys
+import tempfile
+
+import bpy
+
+
+def rounded(value):
+    return round(float(value), 6)
+
+
+def light_report():
+    light = bpy.data.lights.get("WebGapLight")
+    if light is None:
+        raise RuntimeError("WebGapLight is missing")
+    return {
+        "id": "light:WebGapLight",
+        "name": light.name,
+        "lightType": {"POINT": 0, "SUN": 1, "SPOT": 2, "AREA": 4}[light.type],
+        "color": [rounded(value) for value in light.color],
+        "energy": rounded(light.energy),
+        "exposure": rounded(light.exposure),
+        "temperature": rounded(light.temperature),
+        "useTemperature": bool(light.use_temperature),
+        "castsShadow": bool(light.use_shadow),
+        "radius": rounded(light.shadow_soft_size),
+        "spotAngle": rounded(getattr(light, "spot_size", 0.785398)),
+        "spotBlend": rounded(getattr(light, "spot_blend", 0.15)),
+        "areaShape": {"POINT": 0, "DISK": 0, "RECTANGLE": 1, "ELLIPSE": 2}[light.shape] if light.type == "AREA" else 0,
+        "areaSize": rounded(light.size),
+        "areaSizeY": rounded(light.size_y),
+        "areaSpread": rounded(light.spread),
+        "sunAngle": rounded(getattr(light, "angle", 0.00918)),
+    }
+
+
+def main() -> None:
+    arguments = sys.argv[sys.argv.index("--") + 1 :]
+    if len(arguments) != 2:
+        raise SystemExit("usage: blender -b --python check-light-desktop.py -- FIXTURE REPORT")
+    fixture, output = (pathlib.Path(value).resolve() for value in arguments)
+    bpy.ops.wm.open_mainfile(filepath=str(fixture), load_ui=False)
+    before = light_report()
+    descriptor, temporary = tempfile.mkstemp(prefix="m16-light-reopen-", suffix=".blend", dir=fixture.parent)
+    os.close(descriptor)
+    try:
+        bpy.ops.wm.save_as_mainfile(filepath=temporary, check_existing=False, compress=True)
+        bpy.ops.wm.open_mainfile(filepath=temporary, load_ui=False)
+        after = light_report()
+    finally:
+        pathlib.Path(temporary).unlink(missing_ok=True)
+    if before != after:
+        raise RuntimeError(f"light save/reopen drift: {before} != {after}")
+    report = {
+        "schemaVersion": 1,
+        "task": "M16-GAP-00012",
+        "operation": "LIGHT_DATABLOCK_DESKTOP",
+        "fixture": str(fixture),
+        "fixtureSha256": hashlib.sha256(fixture.read_bytes()).hexdigest(),
+        "light": after,
+        "saveReopen": "EXACT",
+        "blenderVersion": bpy.app.version_string,
+    }
+    output.parent.mkdir(parents=True, exist_ok=True)
+    output.write_text(json.dumps(report, indent=2, sort_keys=True) + "\n", encoding="utf-8")
+    print(f"light-desktop-ok id={after['id']} type={after['lightType']} energy={after['energy']} saveReopen=exact")
+
+
+if __name__ == "__main__":
+    main()