| 65 | |
| 66 | @staticmethod |
| 67 | def _generate_vertices(center, radius, height, width): |
| 68 | half_height = height / 2. |
| 69 | half_width = width / 2. |
| 70 | hw = min(half_height, half_width) |
| 71 | |
| 72 | if isinstance(radius, (list, tuple)): |
| 73 | if len(radius) != 4: |
| 74 | raise ValueError("radius must be float or 4 value tuple/list" |
| 75 | " (got %s of length %d)" % (type(radius), |
| 76 | len(radius))) |
| 77 | |
| 78 | if (radius > np.ones(4) * hw).all(): |
| 79 | raise ValueError('Radius of curvature cannot be greater than\ |
| 80 | half of min(width, height)') |
| 81 | radius = np.array(radius, dtype=np.float32) |
| 82 | |
| 83 | else: |
| 84 | if radius > hw: |
| 85 | raise ValueError('Radius of curvature cannot be greater than\ |
| 86 | half of min(width, height)') |
| 87 | radius = np.ones(4) * radius |
| 88 | |
| 89 | num_segments = (radius / hw * 500.).astype(int) |
| 90 | |
| 91 | bias1 = np.ones(4) * half_width - radius |
| 92 | bias2 = np.ones(4) * half_height - radius |
| 93 | |
| 94 | corner1 = np.empty([num_segments[0]+1, 3], dtype=np.float32) |
| 95 | corner2 = np.empty([num_segments[1]+1, 3], dtype=np.float32) |
| 96 | corner3 = np.empty([num_segments[2]+1, 3], dtype=np.float32) |
| 97 | corner4 = np.empty([num_segments[3]+1, 3], dtype=np.float32) |
| 98 | |
| 99 | start_angle = 0. |
| 100 | end_angle = np.pi / 2. |
| 101 | |
| 102 | theta = np.linspace(end_angle, start_angle, num_segments[0]+1) |
| 103 | |
| 104 | corner1[:, 0] = center[0] - bias1[0] - radius[0] * np.sin(theta) |
| 105 | corner1[:, 1] = center[1] - bias2[0] - radius[0] * np.cos(theta) |
| 106 | corner1[:, 2] = 0 |
| 107 | |
| 108 | theta = np.linspace(start_angle, end_angle, num_segments[1]+1) |
| 109 | |
| 110 | corner2[:, 0] = center[0] + bias1[1] + radius[1] * np.sin(theta) |
| 111 | corner2[:, 1] = center[1] - bias2[1] - radius[1] * np.cos(theta) |
| 112 | corner2[:, 2] = 0 |
| 113 | |
| 114 | theta = np.linspace(end_angle, start_angle, num_segments[2]+1) |
| 115 | |
| 116 | corner3[:, 0] = center[0] + bias1[2] + radius[2] * np.sin(theta) |
| 117 | corner3[:, 1] = center[1] + bias2[2] + radius[2] * np.cos(theta) |
| 118 | corner3[:, 2] = 0 |
| 119 | |
| 120 | theta = np.linspace(start_angle, end_angle, num_segments[3]+1) |
| 121 | |
| 122 | corner4[:, 0] = center[0] - bias1[3] - radius[3] * np.sin(theta) |
| 123 | corner4[:, 1] = center[1] + bias2[3] + radius[3] * np.cos(theta) |
| 124 | corner4[:, 2] = 0 |