Laying bridges, a town wall and a gatehouse from the kit

The building recipe can now lay six things that aren’t houses: an arch bridge, a beam bridge, a town wall with a gatehouse three storeys tall, a watchtower, a substation and a sewer outfall. A dead bridge now takes squares out of the walk, which no other building does. The judge also found the dead beam bridge’s rails floating in the game, and fixing that changed all 18 pieces.

How do the new pieces fit together?

The art kit got 18 new steampunk pieces: a beam deck span, a pier, an abutment with its ramp, a rail, stone arch spans of 3 and 6 m, a battlement, a wall-walk, a gatehouse arch span with its portcullis, slit-window walls, a transformer box, a substation fence, an outfall portal, a manhole and a second crossarm for the power pole. Two more are dead versions, a broken beam deck and a fallen 6 m arch.

Each bridge piece has its origin on the ground at its middle. The deck’s walking face is 3.0 m up and the bridge is 3.6 m across, with 3.0 m clear between the parapets. The x axis runs along the bridge, so a span’s ends are flush with the next piece’s.

In the game a new class, BuildingCrossings, lays the kinds from its own table, crossing_kinds.json, so the main kinds table and the wall recipe are untouched. A row with crossing is a walled kind. The recipe makes its walls like any other house, and then the class lays the row’s works over them: slits turns every window wall into an arrow-slit wall, battlements swaps each flat roof’s parapet for a battlement, and gates turns the two ground bays of the front and the back into one gatehouse arch span each, so the way runs straight through. curtain adds wall-walk squares of town wall either side, 6 m up and 3 m thick, with a battlement on the outer edge. A row with yard (the bridges, the substation, the outfall, the manhole) is made whole by BuildingCrossings.plan(). The substation is a fence ring three squares on each side with two transformers and a pole.

What does a dead bridge take from the walk?

Every other building only changes how it looks as it wears. A bridge changes where you can walk. Only a deck span and a pier carry a walk_lost entry in their manifests, which lists the squares they take from the walk as they stand and the squares they would take if broken. The recipe lays those into the plan for each state:

if form == "beam":
    return {"peak": [], "declining": [], "decayed": [[-SQ - 1.5, 0.0]],
            "dead": [[-SQ - 1.5, 0.0], [SQ - 1.5, 0.0]]}
return {"peak": [], "declining": [], "decayed": [], "dead": [[-1.5, 0.0], [1.5, 0.0]]}

SQ is 3.0. A beam bridge loses one square when its first span breaks and two when both do. The arch bridge loses nothing until it’s dead, when the fallen 6 m span takes its two squares. Declining only changes the look. The plan and the pieces agree about which squares those are.

Every guard is higher than the jump. The parapets are 1.10 m and the rail is 1.15 m, against a party jump of 0.893 m.

Why were the rails floating?

The judge passed the kinds in the first round, and the dead arch looked fallen, not unfinished. But in the game the dead beam bridge had rails floating over the deck: two bars with no posts. Every contact sheet had shown the rail whole, so none of them caught it.

The cause was wear. A dead bridge’s wear removed the rail’s posts and left the bars. I fixed it for all 18 pieces. Every part another part rests on is now unbreakable: rail posts, pier caps, merlons, portcullis bars, the transformer’s lid, fence pales and the crossarm’s pins. The far stand-ins, the simple shapes drawn at a distance, keep the posts too. The film now includes a level walk along the arch bridge, because I’d rather check a level switch in a film than trust the sheets.

Why was the gate passage a bright orange room?

You see the passage through its big opening, and its inside faces were lit like any wall. The shader has a new inside_dark option. When it’s on, an inside face (roles 1 to 7, not glass) takes its palette row’s darkest light texel. BuildingLook.material_dark_inside() makes a copy of the look’s material with the option set and caches it, so the time of day and the fog still reach it. Only the gatehouse’s ground storey uses it. It darkens just the faces its rule names, so the floor under the gate’s roof is still bright, and I’ve filed that. The judge agreed on the second round.

Installing the works pieces

The 19 steampunk pieces for the works kind went through the pipeline’s gate and the gate refused none: barn and loading doors, a louvre, a hoist, a dock canopy, a truss, a saw-tooth roof, lattice legs, a sheave, an elevator leg, drum tops, a kiln cap and tall stacks. The gate did catch one real problem. The loading door’s two open leaves stood 1.76 m apart, which left a pocket a body could wedge into under the guard. I fixed it in the kit with one collision box from leaf to leaf over the bay. The mesh didn’t change.

Installing the crossing pieces

The 18 crossing pieces are now installed in the game too. Each went through all 18 steps of the model pipeline and the install gate, and the gate refused none. I built them in a root of their own with all 255 kit pieces, 0 failed, because the lessons check needs the houses, roofs and assemblies as well. They were built twice and came out as the same bytes, and I re-rendered the sheets and read them. No kit change was needed.

The 18 come to 768 KB in all. The largest is the gate arch at 81 KB, with 678 triangles near, 330 at the middle level and 40 far. The smallest is the wall-walk at 16 KB, with 88, 48 and 24. The crossings test went from 127 passed and 39 failed, because its pieces weren’t installed, to 212 passed and 0 failed. 253 steampunk pieces are now installed in all.

What is left

Bridges stand on flat dry ground for now. The recipe will report the gap a bridge spans, so a level can lay one over a cut or water. The wall-walk’s ends are open 6 m drops with no way up. Numbers: 18 pieces, 6 new kinds, a 55 second film. A beam bridge loses 0, 1 or 2 squares across its states and the arch bridge loses 2, only when dead.