library.arch

# A ~50 x 32 m public library around a circular reading room — the SHEET-AND-TABLES example.
#
# 1. CURVED GEOMETRY. The reading room is a drum: a `room circle` for the floor and a
#    `wall` of `arc` edges for the enclosure, the pair `examples/aquarium.arch` introduces.
#    The drum is INSCRIBED in the 16 x 16 m central bay, so it is tangent to all four bay
#    walls and every tangent point is a threshold; the four corner spandrels it leaves
#    (~14 m2 each) belong to no room and carry no schedule row. The circle is written as
#    EIGHT arcs rather than the two semicircles the shape needs, deliberately: the analysis
#    grid behind `describe --json`'s `circulation` rasterises a wall between its VERTICES,
#    so two semicircles lay a phantom chord straight across the room and report the walk to
#    it at 5x its true length. Eight keeps every chord inside the face it stands for, and
#    the DRAWING is identical either way — every face is a true arc, at any zoom.
#
# 2. THE SHEET. `paper A2 landscape` + `scale 1:200` fixes every annotation at a size ON
#    THE SHEET instead of a fraction of a 50 m building, and `schedule rooms` + `legend`
#    fill the margin. Both tables are fully derived, nothing to configure: the legend lists
#    one row per wall hatch MATERIAL used (`concrete` for the shell, the default poche for
#    the partitions) and one per placed fixture CATEGORY that has a plan symbol — wc, basin,
#    kitchen_sink, counter, fridge, stove. Use neither and the table comes out empty.
#
# 3. THE EXPLICIT CURVE CALL-OUTS at the foot of the file. `dim radius <wallId> segment <n>`
#    and `dim diameter <roomId>` take BOTH geometry and text from the element they name, so
#    R8000 and the centre are never retyped. `dims auto` already synthesizes one R per
#    DISTINCT arc (deduplicated by centre+radius, so this eight-arc circle still gets one)
#    and one phi per circular room, in every mode but `walls` — so these two statements are
#    what the sheet would still carry with `dims auto` switched off, and they cost nothing
#    while it is on. Both are zero-offset by contract, which is exactly why neither can trip
#    `W_DIM_INSIDE` or `W_DIM_OVERLAP`: a zero-offset dim sits ON what it measures.
#
# Departments are `zone`s — declared, never inferred from position, and carrying zero
# geometric semantics: the SVG is byte-identical without them. All they add is `zones[]` on
# `describe --json` and the subtotal grouping in the room schedule.
plan "Reading Room Library" {
  units mm
  # `grid 50`, not 100: the partitions are 200 thick and the shell 300, so a fixture
  # placed `flush` against the shell lands on a ...50 coordinate (32000 - 150). A grid of
  # 100 could not express that face and would snap the fixture back into the wall.
  grid 50
  paper A2 landscape
  scale 1:200
  north up
  dims auto all
  schedule rooms
  legend

  # ---- structure: shell in `material concrete`, partitions in the default poche ------
  wall id=shell exterior thickness 300 material concrete { (0,0) (50000,0) (50000,32000) (0,32000) close }

  # The two spine walls: west wing | central bay | east wing.
  wall id=w_west partition thickness 200 { (17000,0) (17000,32000) }
  wall id=w_east partition thickness 200 { (33000,0) (33000,32000) }

  # The bay's cross walls, and the drum inscribed between all four.
  wall id=w_ref_s  partition thickness 200 { (17000,8000) (33000,8000) }
  wall id=w_hall_n partition thickness 200 { (17000,24000) (33000,24000) }

  # Every vertex below is an exact grid-50 point at R8000 from (25000,16000) — 4800/6400 is
  # a 3-4-5 triple scaled — so the eight arcs close a true circle. Walked from the EAST
  # point the default `ccw` runs east -> north -> west -> south, which puts the thresholds
  # at 25% (north), 50% (west) and 75% (south) of the wall's RUN; an arc contributes its
  # arc length R*theta to that run, never its chord.
  wall id=w_drum partition thickness 200 {
    (33000,16000)
    arc (29800,9600)  radius 8000
    arc (25000,8000)  radius 8000
    arc (20200,9600)  radius 8000
    arc (17000,16000) radius 8000
    arc (20200,22400) radius 8000
    arc (25000,24000) radius 8000
    arc (29800,22400) radius 8000
    arc (33000,16000) radius 8000
  }

  # Both wings carry a 3 m aisle on the drum's centre line, so each meets it at a tangent.
  wall id=w_waisle_n partition thickness 200 { (0,14500) (17000,14500) }
  wall id=w_waisle_s partition thickness 200 { (0,17500) (17000,17500) }

  wall id=w_cafe_e   partition thickness 200 { (44000,0) (44000,14500) }
  wall id=w_eaisle_n partition thickness 200 { (33000,14500) (50000,14500) }
  wall id=w_eaisle_s partition thickness 200 { (33000,17500) (50000,17500) }
  wall id=w_staff_s  partition thickness 200 { (33000,24000) (50000,24000) }
  wall id=w_lobby_s  partition thickness 200 { (33000,27000) (50000,27000) }
  wall id=w_wcw_e    partition thickness 200 { (39000,27000) (39000,32000) }
  wall id=w_wcm_e    partition thickness 200 { (45000,27000) (45000,32000) }

  # ---- axes: the STRAIGHT structural grid only; a curve's radius is its dimension ----
  axes {
    x at 0, 17000, 33000, 44000, 50000
    y at 0, 14500, 17500, 24000, 27000, 32000
  }

  # ---- rooms, grouped by department -----------------------------------------
  zone public "Public" {
    room id=r_hall     at (17000,24000) size 16000x8000  label "Entrance Hall"      uses entry hall
    room id=r_reading  circle at (25000,16000) radius 8000 label "Reading Room" at (25000,17200) uses hall
    room id=r_children at (0,17500)     size 17000x14500 label "Children's Library" uses living
    room id=r_waisle   at (0,14500)     size 17000x3000  label "West Aisle"         uses circulation
    room id=r_cafe     at (33000,0)     size 11000x14500 label "Cafe"               uses dining
    room id=r_eaisle   at (33000,14500) size 17000x3000  label "East Aisle"         uses circulation
    room id=r_lobby    at (33000,24000) size 17000x3000  label "WC Lobby"           uses circulation
    room id=r_wc_w     at (33000,27000) size 6000x5000   label "WC Women"           uses wc
    room id=r_wc_m     at (39000,27000) size 6000x5000   label "WC Men"             uses wc
  }

  zone stacks "Stacks" {
    room id=r_stacks at (0,0)     size 17000x14500 label "Open Stacks" at (8500,12400) uses storage
    room id=r_ref    at (17000,0) size 16000x8000  label "Reference Stacks" uses storage
  }

  zone staff "Staff" {
    room id=r_staff   at (33000,17500) size 17000x6500  label "Staff Workroom" uses office
    room id=r_kitchen at (44000,0)     size 6000x14500  label "Cafe Kitchen"   uses kitchen
    room id=r_plant   at (45000,27000) size 5000x5000   label "Plant Room"     uses utility
  }

  # ---- thresholds -----------------------------------------------------------
  # The drum is tangent to each bay wall at one point, so a threshold there has to be cut
  # through BOTH faces — the arc and the straight wall it touches — or the poche of the
  # second one still stands in the doorway. Each pair below is one physical opening.
  opening id=o_drum_s  on w_drum   at 75%   width 3000
  opening id=o_hall_n  on w_hall_n at 50%   width 3000
  opening id=o_drum_n  on w_drum   at 25%   width 3000
  opening id=o_ref_s   on w_ref_s  at 50%   width 3000
  opening id=o_drum_w  on w_drum   at 50%   width 2400
  opening id=o_west_16 on w_west   at 16000 width 2400

  # The rest of the public route.
  door id=d_main at (25000,32000) width 2400 wall shell swing into r_hall
  opening id=o_hall_children on w_west at 28000 width 3000
  opening id=o_hall_lobby    on w_east at 25500 width 3000
  opening id=o_ref_stacks    on w_west at 4000  width 2400
  opening id=o_stacks_aisle  on w_waisle_n at 50% width 3000
  opening id=o_children_aisle on w_waisle_s at 50% width 3000
  opening id=o_cafe_aisle    on w_eaisle_n at 5500 width 3000
  opening id=o_staff_aisle   on w_eaisle_s at 8500 width 2400

  # Staff and service doors. The cafe kitchen keeps a pocket door off the aisle so no leaf
  # swings into a 3 m corridor, and its own service door onto the east yard.
  door id=d_kitchen pocket on w_eaisle_n at 14000 width 1000 slide right
  door id=d_cafe_kitchen on w_cafe_e at 50% width 1000 swing into r_kitchen
  door id=d_service at (50000,13000) width 1200 wall shell swing out
  door id=d_staff_lobby on w_staff_s at 2500 width 1000 swing into r_lobby
  door id=d_wc_w  on w_lobby_s at 1500  width 1000 swing into r_wc_w
  door id=d_wc_m  on w_lobby_s at 7500  width 1000 swing into r_wc_m
  door id=d_plant on w_lobby_s at 13000 width 900  swing into r_plant

  # ---- glazing --------------------------------------------------------------
  window at (6000,0)      width 4000 wall shell
  window at (12000,0)     width 4000 wall shell
  window at (21000,0)     width 3000 wall shell
  window at (29000,0)     width 3000 wall shell
  window at (38500,0)     width 4000 wall shell
  window at (0,6000)      width 3000 wall shell
  window at (0,16000)     width 2000 wall shell
  window at (0,24000)     width 4000 wall shell
  window at (50000,10500) width 1600 wall shell
  window at (50000,20500) width 3000 wall shell
  window at (6000,32000)  width 4000 wall shell
  window at (12000,32000) width 4000 wall shell
  window at (20000,32000) width 3000 wall shell
  window at (30000,32000) width 3000 wall shell
  window at (36000,32000) width 1200 wall shell
  window at (42000,32000) width 1200 wall shell

  # ---- vertical circulation, side by side in the hall -----------------------
  # A single-storey plan still draws both symbols; `W_STAIR_UNMATCHED` is a multi-storey
  # question and never fires here.
  stair id=st_main at (28500,26500) size 1400x4500 dir up
  elevator id=lift_main at (30500,28000) size 2200x2200

  # ---- fit-out --------------------------------------------------------------
  # Reading tables ride the drum's chord lines, leaving the centre band clear for the phi
  # call-out and the west threshold.
  furniture table at (21500,9800)  size 7000x1400 label "Reading table"
  furniture table at (20500,12200) size 9000x1400 label "Reading table"
  furniture table at (20500,18400) size 9000x1400 label "Reading table"
  furniture table at (21500,20800) size 7000x1400 label "Reading table"

  for i in 0..5 {
    furniture shelf at (2000, 1500 + i * 2200) size 13000x600 label "Stacks"
  }
  for i in 0..4 {
    furniture shelf at (18500 + i * 3200, 1200) size 600x5000 label "Reference"
  }
  for i in 0..3 {
    furniture table at (2500 + i * 4500, 19500) size 2000x2000 label "Table"
    furniture table at (2500 + i * 4500, 23500) size 2000x2000 label "Table"
    furniture shelf at (2000 + i * 4500, 28500) size 3000x500 label "Picture books"
  }
  for i in 0..5 {
    furniture desk at (34500 + i * 3000, 18500) size 1600x800 label "Desk"
    furniture desk at (34500 + i * 3000, 22000) size 1600x800 label "Desk"
  }
  for i in 0..3 {
    furniture table at (34500 + i * 3000, 2500) size 1600x1600 label "Table"
    furniture table at (34500 + i * 3000, 6500) size 1600x1600 label "Table"
  }

  furniture sofa    at (2000,27500)  size 2400x900 label "Story bench"
  furniture sofa    at (18000,30000) size 2400x900 label "Seating"
  furniture sofa    at (21000,30000) size 2400x900 label "Seating"
  furniture counter against wall w_hall_n offset 4000 size 4000x700 label "Enquiries" in r_hall
  furniture plant   at (18500,29000) size 700x700 in r_hall
  furniture counter against wall w_cafe_e offset 3000 size 4000x700 label "Servery" in r_cafe

  # Catalogued fixtures need no `size`: the footprint, the depth off the wall face and the
  # quarter-turn all come from the wall and the catalogue.
  furniture table at (45000,2500) size 3600x900 label "Prep"
  furniture table at (45000,4600) size 3600x900 label "Prep"
  furniture kitchen_sink against wall shell segment 1 offset 2000 in r_kitchen
  furniture counter      against wall shell segment 1 offset 3600 in r_kitchen
  furniture fridge       against wall shell segment 1 offset 5200 in r_kitchen
  furniture stove        against wall shell segment 1 offset 6800 in r_kitchen

  furniture wc    against wall shell segment 2 offset 11500 in r_wc_w
  furniture wc    against wall shell segment 2 offset 13000 in r_wc_w
  furniture wc    against wall shell segment 2 offset 14500 in r_wc_w
  furniture basin against wall w_east offset 28000 in r_wc_w
  furniture basin against wall w_east offset 29500 in r_wc_w

  furniture wc    against wall shell segment 2 offset 5500 in r_wc_m
  furniture wc    against wall shell segment 2 offset 7000 in r_wc_m
  furniture wc    against wall shell segment 2 offset 8500 in r_wc_m
  furniture basin against wall w_wcw_e offset 1000 in r_wc_m
  furniture basin against wall w_wcw_e offset 2500 in r_wc_m

  # ---- the explicit curve call-outs (see the head of the file) --------------
  dim radius w_drum segment 0
  dim diameter r_reading

  title {
    project "Reading Room Library"
    drawn_by "ArchLang"
    date "2026-08-16"
  }
}