diff options
Diffstat (limited to 'gerbonara/gerber/graphic_primitives.py')
| -rw-r--r-- | gerbonara/gerber/graphic_primitives.py | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/gerbonara/gerber/graphic_primitives.py b/gerbonara/gerber/graphic_primitives.py index 4e176b2..1b9f09b 100644 --- a/gerbonara/gerber/graphic_primitives.py +++ b/gerbonara/gerber/graphic_primitives.py @@ -177,14 +177,22 @@ def point_line_distance(l1, l2, p): return abs((x2-x1)*(y1-y0) - (x1-x0)*(y2-y1)) / length def svg_arc(old, new, center, clockwise): - print(f'{old=} {new=} {center=}') - r = point_distance(old, new) + r = point_distance(old, center) d = point_line_distance(old, new, center) # invert sweep flag since the svg y axis is mirrored sweep_flag = int(not clockwise) - large_arc = int((d > 0) == clockwise) # FIXME check signs - print(f'{r=:.3} {d=:.3} {sweep_flag=} {large_arc=} {clockwise=}') - return f'A {r:.6} {r:.6} 0 {large_arc} {sweep_flag} {new[0]:.6} {new[1]:.6}' + # In the degenerate case where old == new, we always take the long way around. To represent this "full-circle arc" + # in SVG, we have to split it into two. + if math.isclose(point_distance(old, new), 0): + intermediate = center[0] + (center[0] - old[0]), center[1] + (center[1] - old[1]) + # Note that we have to preserve the sweep flag to avoid causing self-intersections by flipping the direction of + # a circular cutin + return f'A {r:.6} {r:.6} 0 1 {sweep_flag} {intermediate[0]:.6} {intermediate[1]:.6} ' +\ + f'A {r:.6} {r:.6} 0 1 {sweep_flag} {new[0]:.6} {new[1]:.6}' + + else: # normal case + large_arc = int((d > 0) == clockwise) + return f'A {r:.6} {r:.6} 0 {large_arc} {sweep_flag} {new[0]:.6} {new[1]:.6}' @dataclass class ArcPoly(GraphicPrimitive): |