自测：这是什么等距变换？

GeoGebra 命令及参数

1. Polygon(B, C, A) → t1, a, b, c
2. Vector(E, D) → u
3. Angle(D, E, F) → α
4. Translate(B, u) → B'
5. Translate(C, u) → C'
6. Translate(A, u) → A'
7. Polygon(B', C', A') → t1', a', b', c'
8. Rotate(B, α, E) → B'_1
9. Rotate(C, α, E) → C'_1
10. Rotate(A, α, E) → A'_1
11. Polygon(B'_1, C'_1, A'_1) → t1'_1, a'_1, b'_1, c'_1
12. Line(E, D) → f
13. Mirror(B, f) → B'_2
14. Mirror(C, f) → C'_2
15. Mirror(A, f) → A'_2
16. Polygon(B'_2, C'_2, A'_2) → t1'_2, a'_2, b'_2, c'_2
17. Mirror(B', f) → B''
18. Mirror(C', f) → C''
19. Mirror(A', f) → A''
20. Polygon(B'', C'', A'') → t1'', a'', b'', c''
21. Corner(1) → BL
22. Corner(2) → BR
23. Corner(3) → TR
24. Corner(4) → TL
25. Polygon(BL, BR, TR, TL) → q1, bl, br, tr, tl
26. Dilate(BL, e, CTR) → BL'
27. Dilate(BR, e, CTR) → BR'
28. Dilate(TR, e, CTR) → TR'
29. Dilate(TL, e, CTR) → TL'
30. Polygon(BL', BR', TR', TL') → q1', bl', br', tr', tl'
31. Vector((30 * CTR) - (10 * (A + B + C))) → v
32. Segment(BL, TR) → i
33. Circle(E, i) → p
34. Angle(A, E, A'_1) → β
35. Ray(E, A) → j
36. Ray(E, A'_1) → k
37. Vector(A, A') → w
38. Segment(A', A'') → l
39. Vector(B, B') → m
40. Vector(C, C') → n
41. Segment(B', B'') → q
42. Segment(C', C'') → s
43. Segment(A, A'_2) → r
44. Segment(B, B'_2) → t
45. Segment(C, C'_2) → f_1
46. CircleArc(E, A, A'_1) → c_1
47. CircleArc(E, A'_1, A) → d_1
48. CircleArc(E, B, B'_1) → e_1
49. CircleArc(E, B'_1, B) → g_1
50. CircleArc(E, C, C'_1) → h_1
51. CircleArc(E, C'_1, C) → k_1
52. Join({If[a_t, {1}, {}], If[a_{rho}, {2}, {}], If[a_{ref}, {3}, {}], If[a_{gr}, {4}, {}]}) → choices