source $drc_test_source
target $drc_test_target

if $drc_test_deep
  deep
end

gate    = input(1, 0)
contact = input(2, 0)
metal1  = input(3, 0)
via1    = input(4, 0)
metal2  = input(5, 0)
via2    = input(6, 0)
metal3  = input(7, 0)
via3    = input(8, 0)
metal4  = input(9, 0)

source.layers.each do |lp|
  input(lp).output(lp)
end

# Incrementally connect the metal stack, starting
# from gate, up to metal4.
# On each level, compute the antenna ratio of last
# metal area vs. gate area. Record the ratio in different
# layers.
# Then combine the layers and compute the cumulative 
# ratio. Select gate shapes according to that ratio.

connect(gate, contact)
connect(contact, metal1)

# place metal1/gate area ratio in property #1
ar_m1 = evaluate_nets(gate, { "m" => metal1 }, "put(1, area(m)/area)")

# Note: incremental connect
connect(metal1, via1)
connect(via1, metal2)

# place metal2/gate area ratio in property #2
ar_m2 = evaluate_nets(gate, { "m" => metal2 }, "put(2, area(m)/area)")

# Note: incremental connect
connect(metal2, via2)
connect(via2, metal3)

# place metal3/gate area ratio in property #3
ar_m3 = evaluate_nets(gate, { "m" => metal3 }, "put(3, area(m)/area)")

# Note: incremental connect
connect(metal3, via3)
connect(via3, metal4)

# place metal4/gate area ratio in property #4
ar_m4 = evaluate_nets(gate, { "m" => metal4 }, "put(4, area(m)/area)")

# merge properties #1 to #4: produces a set of properties on each shape
# Note: "merged_props" will merge the shapes and while doing so, combine
# the properties. As the propery names are all different, we get a list
# of area ratios on each shape.
ar_all = (ar_m1 + ar_m2 + ar_m3 + ar_m4).merged_props

# we do not need these layers anymore
ar_m1.forget
ar_m2.forget
ar_m3.forget
ar_m4.forget

# compute the sum of the area ratios in property #10
ar_all.evaluate("put(10, value(1)+value(2)+value(3)+value(4))", {}, true)

# output for debugging 
ar_all.output(1000, 0)

# select based on the cumulative area ratio
errors = ar_all.selected_if("value(10)>=ar_max", { "ar_max" => 3.0 })

# output errors
errors.output(1001, 0)