旋转多边形动画

GeoGebra 命令及参数

1. Segment(A, B) → a
2. OrthogonalLine(B, a) → b
3. Point(b) → E
4. Ray(B, E) → c
5. Angle(A, B, E) → α
6. Point(c) → C
7. Segment(C, A) → d
8. Angle(B, C, A) → β
9. Segment(B, C) → e
10. Rotate(B, If[0 < f ≤ 1, (f * β), β], C) → B'
11. Rotate(C, If[0 < f ≤ 1, (f * β), 0], C) → C'
12. Segment(B', C') → e'
13. Angle(C, A, B) → γ
14. Rotate(A, If[0 < g ≤ 1, ((-g) * γ), 0], A) → A'
15. Rotate(B, If[0 < g ≤ 1, ((-g) * γ), 0], A) → B'_1
16. Segment(A', B'_1) → a'
17. Rotate(B, If[0 < h ≤ 1, ((-h) * α), 0], B) → B'_2
18. Rotate(C, If[0 < h ≤ 1, ((-h) * α), 0], B) → C'_1
19. Segment(B'_2, C'_1) → e'_1
20. Polygon(B, A, C) → poly1, c_1, b_1, a_1
21. Midpoint(e') → D
22. Vector(F, D) → u
23. Midpoint(a') → G
24. Vector(H, G) → v
25. Midpoint(e'_1) → I
26. Vector(J, I) → w
27. Ray(B, A) → j