| """ | |
| # Copyright 2020 Adobe | |
| # All Rights Reserved. | |
| # NOTICE: Adobe permits you to use, modify, and distribute this file in | |
| # accordance with the terms of the Adobe license agreement accompanying | |
| # it. | |
| """ | |
| import numpy as np | |
| def area_of_triangle(pts): | |
| AB = pts[1, :] - pts[0, :] | |
| AC = pts[2, :] - pts[0, :] | |
| return 0.5 * np.linalg.norm(np.cross(AB, AC)) | |
| def area_of_polygon(pts): | |
| l = pts.shape[0] | |
| s = 0 | |
| for i in range(1, l-1): | |
| s += area_of_triangle(pts[(0, i, i+1), :]) | |
| return s | |
| def area_of_signed_triangle(pts): | |
| AB = pts[1, :] - pts[0, :] | |
| AC = pts[2, :] - pts[0, :] | |
| return 0.5 * np.cross(AB, AC) | |
| def area_of_signed_polygon(pts): | |
| l = pts.shape[0] | |
| s = 0 | |
| for i in range(1, l-1): | |
| s += area_of_signed_triangle(pts[(0, i, i+1), :]) | |
| return s |