BT411/scratchpad/night6/bench_common.sh

#!/usr/bin/env bash
# ===========================================================================
# BENCH COMMON -- launch a local test node EXACTLY as a field player's
# shortcut does, so what we see locally is what they see.
#
# WHY THIS FILE EXISTS (2026-07-30): local benches had drifted from the
# shipped launchers, and every divergence cost a debugging session:
#   * no BT_START_INSIDE  -> benches opened in the EXTERNAL CHASE camera while
#                            every player starts in the COCKPIT.  Hours were
#                            spent on a "broken HUD" that was simply the first
#                            first-person look at a view the benches never showed.
#   * novice bench eggs   -> every SHIPPED egg is `expert`; novice silences the
#                            whole heat model, crits and jams, so bench combat
#                            was not the combat players get.
#   * 1-logical-processor affinity pins -> starved the gauge executive and
#                            produced a false "the comms panel never counts"
#                            reading.  Two LPs per node keeps MP jitter pinned
#                            (the documented single-box fix) without starving.
#
# THE PLAYER ENV IS THE CONTRACT.  It is copied verbatim from the shipped
# play_solo.bat / join.bat (dist zip).  bt_assert_player_env compares this
# list against a shipped .bat when one is available, so drift is caught.
# ===========================================================================

BT_ROOT=/c/git/bt411
BT_EXE=$BT_ROOT/build/Release/btl4.exe

# PIDs THIS run launched.  A blanket `taskkill /IM btl4.exe` at teardown kills
# every game on the machine -- including a NEWER bench a previous wrapper's
# sleep outlived.  That silently shot down two live sessions, so each run now
# tracks and kills only its own children.
BT_PIDFILE=/tmp/bt_bench_pids.$$

# --- the exact env every shipped launcher sets -----------------------------
bt_player_env () {
  export BT_PLATFORM=glass        # unified build, desktop cockpit layer
  export BT_START_INSIDE=1        # COCKPIT eyepoint -- what a player sees
  export BT_DEV_GAUGES=1          # MFD/gauge surfaces + cockpit surround
}

# --- warn if the shipped launcher has gained/lost a setting ----------------
bt_assert_player_env () {
  local bat="$BT_ROOT/dist/BT411_4.11.643/play_solo.bat"
  [ -f "$bat" ] || return 0
  for v in BT_PLATFORM BT_START_INSIDE BT_DEV_GAUGES; do
    grep -qi "set $v=" "$bat" || echo "[bench] WARNING: shipped bat no longer sets $v"
  done
}

# --- launch one node -------------------------------------------------------
# bt_launch <logfile> <egg> <affinity> [extra args...]   (env: extra BT_* vars)
# Two logical processors per node: disjoint core sets keep single-box packet
# delivery even (peer-shakiness fix) without starving the gauge executive.
bt_launch () {
  local log="$1" egg="$2" aff="$3"; shift 3
  ( bt_player_env
    export BT_LOG="$log" BT_AFFINITY="$aff"
    "$BT_EXE" -egg "$egg" "$@" &
    # the winpid pseudo-file races process start -- poll briefly; a missed pid
    # here left a stale node holding the -net port and null-ran the next config
    for _i in 1 2 3 4 5; do
      [ -f /proc/$!/winpid ] && { cat /proc/$!/winpid >> "$BT_PIDFILE"; break; }
      sleep 0.3
    done )
}

# --- an EXPERT copy of an egg (what players actually fly) ------------------
# Shipped eggs are all experience=expert.  Bench eggs must match unless the
# harness itself needs otherwise (see bt_novice_egg).
bt_expert_egg () {   # bt_expert_egg <src.egg> <dst.egg>
  sed 's/^experience=.*/experience=expert/' "$1" > "$2"
}

# --- a NOVICE copy, for the harnesses that genuinely require it ------------
# ONLY the aimed-leg gimp bench: on expert the self-damage bursts roll CRITS on
# the aimed leg, and one myomers crit leaves the mech turning-but-not-moving --
# which destroys the limp demo.  Novice gates crits; the leg gimp still fires.
# Any bench using this is NOT showing player-authentic damage behaviour.
bt_novice_egg () {   # bt_novice_egg <src.egg> <dst.egg>
  sed 's/^experience=.*/experience=novice/' "$1" > "$2"
  echo "[bench] NOTE: novice egg $2 -- crits/heat/jams are GATED OFF (harness requirement)"
}

# --- kill ONLY the nodes this run started --------------------------------
bt_kill_ours () {
  [ -f "$BT_PIDFILE" ] || return 0
  while read -r pid; do
    [ -n "$pid" ] && taskkill //F //PID "$pid" > /dev/null 2>&1
  done < "$BT_PIDFILE"
  rm -f "$BT_PIDFILE"
}