Add a tool that measures emotes from a store's 3D preview

tools/capture drives a store page's skin viewer in headless Firefox, stepping its clock one tick at
a time and taking every tick from ten fixed cameras. It then fits our own rig to the frames by
rendering the model (a Python port of LimbBend and PoseApplier) and matching outlines and colours,
and writes the result as Emotecraft JSON. It measures pixels only and never reads the page's
animation data. The README covers the steps, the checks and the limits.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

tools/capture/sheet.py

@@ -0,0 +1,20 @@
+"""Tiles frames into a contact sheet: rows are views, columns are ticks, cropped to the player."""
+import sys
+from pathlib import Path
+
+import numpy as np
+from PIL import Image
+
+name, views, ticks = sys.argv[1], sys.argv[2].split(","), range(*map(int, sys.argv[3].split(":")))
+out = sys.argv[4] if len(sys.argv) > 4 else "sheet.png"
+frames = [[Image.open(Path("frames") / name / v / f"{t:04d}.png") for t in ticks] for v in views]
+alpha = np.maximum.reduce([np.asarray(f)[:, :, 3] for row in frames for f in row])
+ys, xs = np.nonzero(alpha)
+box = (xs.min() - 4, ys.min() - 4, xs.max() + 4, ys.max() + 4)
+w, h = box[2] - box[0], box[3] - box[1]
+sheet = Image.new("RGBA", (w * len(ticks), h * len(views)), (40, 40, 52, 255))
+for r, row in enumerate(frames):
+    for c, f in enumerate(row):
+        sheet.alpha_composite(f.crop(box), (c * w, r * h))
+sheet.save(out)
+print(sheet.size)