improve A* router

import gdsfactory as gf

c = gf.Component("get_route_astar")
w = gf.components.straight()
left = c << w
right = c << w
right.move((100, 80))

obstacle = gf.components.rectangle(size=(100, 10))
obstacle1 = c << obstacle
obstacle2 = c << obstacle
obstacle1.ymin = 40
obstacle2.xmin = 25

port1 = left.ports["o2"]
port2 = right.ports["o2"]

routes = gf.routing.get_route_astar(
    component=c,
    port1=port1,
    port2=port2,
)
c.add(routes.references)
c.show()

import gdsfactory as gf

cross_section = "metal1"

c = gf.Component("get_route_astar")
w = gf.components.straight(cross_section=cross_section)

left = c << w
right = c << w
right.move((100, 80))

obstacle = gf.components.rectangle(size=(100, 10), layer="M1")
obstacle1 = c << obstacle
obstacle2 = c << obstacle
obstacle1.ymin = 40
obstacle2.xmin = 25

port1 = left.ports["e2"]
port2 = right.ports["e2"]

routes = gf.routing.get_route_astar(
    component=c, port1=port1, port2=port2, cross_section="metal1", resolution=5
)
c.add(routes.references)
c.show()

"""FIXME.

We need to add an option to avoid specific layers
"""

if __name__ == "__main__":
    import gdsfactory as gf

    c = gf.Component()

    rect1 = c << gf.components.rectangle()
    rect2 = c << gf.components.rectangle()
    rect3 = c << gf.components.rectangle((2, 2), layer=(2, 0))
    rect2.move(destination=(8, 4))
    rect3.move(destination=(5.5, 1.5))

    port1 = gf.Port(
        "o1", 0, rect1.center + (0, 3), cross_section=gf.get_cross_section("strip")
    )
    port2 = port1.copy("o2")
    port2.orientation = 180
    port2.center = rect2.center + (0, -3)
    c.add_ports([port1, port2])
    route = gf.routing.get_route_astar(c, port1, port2, radius=0.5, width=0.5)
    c.add(route.references)

    c.show(show_ports=True)

@SkandanC

[joamatab]

nice 🎉

looks great Skandan

[joamatab]

nice, this looks much better, looking forward to your PR

it would be nice to add an optional avoid_layers: List[LayerSpec] of layers that it needs to avoid, for example,

metal1 only needs to avoid shapes in metal1 , and does not need to avoid waveguide layer

i would use c.get_polygons(layers) so we only compute the bbox for the important layers that we need to avoid

also you could also include an optional distance:float parameter that avoids being too close to obstacles in the picture above