measure_template.py

skills/artwork-template-rebuilder/scripts/measure_template.py

1. #!/usr/bin/env python3
2. """
3. measure_template.py - Measure a vendor template's real geometry so the rebuild
4. reproduces the SAME safe-line inset the vendor drew, template by template.
6. This is the source of truth for dimensions. It does NOT read stated text labels
7. ("Visual Area: X") and it does NOT guess a default. It finds the dashed safe-line
8. rectangle the vendor actually drew and reports the bleed size + visual size in
9. inches, plus the exact flags to hand to build_template.py.
11. Usage:
12. python measure_template.py /path/to/vendor.pdf
14. Strategy:
15. - Page MediaBox (in inches) = the bleed / outer boundary.
16. - Collect every DASHED rectangle on the page (the safe line is always dashed).
17. When colors are recoverable, a green or red dashed rect is the safe line; the
18. innermost dashed rect wins when there are several (e.g. a red cut + green safe).
19. - visual_w/visual_h = that rect's width/height in inches.
20. - Insets are reported per side. If left!=right or top!=bottom beyond tolerance,
21. it warns: build_template.py centers the visual area, so a non-centered safe line
22. can't be reproduced exactly without the per-side path.
24. If NO dashed rect is found, it says so plainly and emits no dimensions - the agent
25. must then fall back (stated text, or a documented default) and TELL the user it did.
26. """
27. import sys
28. import pdfplumber
30. TOL_IN = 0.05 # inches; inset asymmetry below this is treated as centered/rounding
33. def _in(pts):
34. return pts / 72.0
37. def measure(path):
38. pdf = pdfplumber.open(path)
39. page = pdf.pages[0]
40. page_w_in, page_h_in = _in(float(page.width)), _in(float(page.height))
42. # gather dashed rectangles (pdfplumber stores dash as ([pattern], phase) or None)
43. dashed = []
44. for r in page.rects:
45. dash = r.get("dash")
46. is_dashed = bool(dash and dash[0])
47. if not is_dashed:
48. continue
49. x0, x1 = float(r["x0"]), float(r["x1"])
50. top, bottom = float(r["top"]), float(r["bottom"])
51. w_in = _in(abs(x1 - x0))
52. h_in = _in(abs(bottom - top))
53. # insets from page edge, in inches (top/bottom from pdfplumber are top-origin)
54. ins_left = _in(x0)
55. ins_right = page_w_in - _in(x1)
56. ins_top = _in(top)
57. ins_bottom = page_h_in - _in(bottom)
58. dashed.append({
59. "w_in": w_in, "h_in": h_in,
60. "left": ins_left, "right": ins_right,
61. "top": ins_top, "bottom": ins_bottom,
62. "color": r.get("stroke_color"),
63. "area": w_in * h_in,
64. })
66. print(f"FILE: {path}")
67. print(f"BLEED (page MediaBox): {page_w_in:.2f} W x {page_h_in:.2f} H in")
68. print(f"dashed rects found: {len(dashed)}")
70. if not dashed:
71. print("\nNO DASHED SAFE LINE FOUND.")
72. print("=> Do NOT guess silently. Fall back to a stated visual size if the file")
73. print(" gives one, else a documented default, and TELL THE USER what you used.")
74. return
76. # innermost dashed rect = safe line (smallest area). Color, when present, is a tiebreak.
77. dashed.sort(key=lambda d: d["area"])
78. safe = dashed[0]
80. asym_x = abs(safe["left"] - safe["right"]) > TOL_IN
81. asym_y = abs(safe["top"] - safe["bottom"]) > TOL_IN
83. print("\nSAFE LINE (innermost dashed rect):")
84. print(f" visual size : {safe['w_in']:.2f} W x {safe['h_in']:.2f} H in")
85. print(f" insets (in) : left {safe['left']:.2f} right {safe['right']:.2f} "
86. f"top {safe['top']:.2f} bottom {safe['bottom']:.2f}")
87. if safe["color"] is not None:
88. print(f" stroke color: {safe['color']}")
89. if asym_x or asym_y:
90. print(" WARNING: safe line is not centered on the page "
91. f"({'L!=R ' if asym_x else ''}{'T!=B' if asym_y else ''}). "
92. "build_template.py centers the visual area, so this won't reproduce exactly. "
93. "Flag it to the user.")
95. print("\nPASS TO build_template.py:")
96. print(f" --bleed-w {page_w_in:.2f} --bleed-h {page_h_in:.2f} "
97. f"--visual-w {safe['w_in']:.2f} --visual-h {safe['h_in']:.2f}")
100. if __name__ == "__main__":
101. if len(sys.argv) != 2:
102. print("usage: python measure_template.py /path/to/vendor.pdf")
103. sys.exit(1)
104. measure(sys.argv[1])