G2 support

src/core/gen2/TradeAnim.lua

@@ -0,0 +1,274 @@
+-- The in-game trade animation (engine/movie/trade_animation.asm
+-- TradeAnimation), the cable-and-ball sequence NPCTrade runs between
+-- DoNPCTrade and TradedForText.
+--
+-- love-free: this file is the script and its clock, src/ui/gen2/TradeAnim.lua
+-- is the half that draws.  Nothing about the trade's outcome depends on any of
+-- it -- DoNPCTrade has already swapped the two mons by the time the first
+-- frame runs -- which is why the screen can be skipped without a branch.
+--
+-- The cart drives this from a byte script (`tradeanim` rows into
+-- DoTradeAnimation.Jumptable), one command per frame, and each command either
+-- runs a piece of setup and advances the pointer or sits on wFrameCounter
+-- until it drains.  The commands that only set something up (a palette, a
+-- window position, a sprite struct) cost no frames, so the whole script
+-- flattens to the list of WAITS below, with the setup a command did folded
+-- into the `cue` of the beat that follows it.  Two examples, since the folding
+-- is the one place this stops being a transcription:
+--
+--   * TradeAnim_Poof sets wFrameCounter to 16 and advances immediately, so the
+--     poof is still on screen while TradeAnim_EnterLinkTube2 slides the cable
+--     in over its first 40 frames.  It gets no beat of its own; `tube_in`
+--     carries the "poof" cue and the drawing side gives the puff 16 frames.
+--   * TradeAnim_RockingBall's 64 frames are only spent later, by the
+--     TradeAnim_WaitAnim that follows EnterLinkTube2's own 40 + 80 -- the two
+--     commands in between never touch wFrameCounter.  That wait is `ball_rock`.
+--
+-- The frame counts are the cart's own: `ld c, 80 / call DelayFrames`,
+-- `ld a, 92 / ld [wFrameCounter], a`, and the scrolls' step per frame.
+--
+-- Only the player-1 script is here.  TradeAnimationPlayer2 is the same beats
+-- in the other order and is reached from the cable club, which the port does
+-- not have.
+
+local TradeAnim = {}
+
+-- Scroll steps, in pixels per frame.
+--
+-- TradeAnim_DoGivemonScroll moves hWX and hSCX 4 a frame until the window is
+-- home; TradeAnim_EnterLinkTube2 / TradeAnim_ExitLinkTube move hSCX 4 a frame
+-- over the tube's own $a0; the two Game Boy pans move hSCX 2 a frame.
+TradeAnim.SCROLL_STEP = 4
+TradeAnim.PAN_STEP = 2
+
+-- hSCX starts at $88 for the frontpic scroll and hWX at $8f, i.e. both are
+-- $88 from home.
+TradeAnim.GIVEMON_SCROLL = 0x88
+-- The link tube enters and leaves across $a0.
+TradeAnim.TUBE_SCROLL = 0xa0
+
+-- The Game Boy pan is a full wrap of the 256-pixel BG map: hSCX runs
+-- 0 -> $50 -> $a0 -> $100, redrawing the tilemap at each boundary in the part
+-- of the map the window has already left, so the three states read as one
+-- continuous scene 256 pixels long.  TradeAnim_InitTubeAnim's own
+-- `hlbgcoord 20, 3 / ld bc, 12 / ld a, $60 / ByteFill` is what keeps the cable
+-- unbroken across the seam.
+TradeAnim.PAN_TOTAL = 0x100
+
+-- The script.  `frames` is how long the beat holds, `cue` fires on its first
+-- frame.
+--
+-- The two Game Boy pans are one beat per hSCX target rather than one long one
+-- because the cart really does stop at $50 and $a0 to swap the tilemap, and a
+-- beat boundary is where the drawing side gets to notice.
+TradeAnim.SCRIPT = {
+  -- ShowGivemonData, then TradeAnim_DoGivemonScroll's $88 at 4 a frame.
+  { id = "givemon_scroll", frames = 34, cue = "show_give" },
+  { id = "givemon_hold", frames = 80 },
+  -- Poof, RockingBall, EnterLinkTube1: the mon becomes a ball and the cable
+  -- slides in over it.
+  { id = "tube_in", frames = 40, cue = "poof" },
+  -- EnterLinkTube2's `ld c, 80 / call DelayFrames` once hSCX is home.
+  { id = "tube_hold", frames = 80 },
+  -- The WaitAnim spending RockingBall's 64.
+  { id = "ball_rock", frames = 64 },
+  { id = "bulge", frames = 128, cue = "bulge" },
+  -- GiveTrademonSFX, then TubeToOT2/3/4.
+  { id = "send_pan_a", frames = 40, cue = "give_sfx" },
+  { id = "send_pan_b", frames = 40 },
+  { id = "send_pan_c", frames = 48 },
+  -- TubeToOT5 spends the 92 TubeToOT1 set, TubeToOT6/7 the 128 after it.
+  { id = "send_wait", frames = 92 },
+  { id = "send_hold", frames = 128 },
+  -- SentToOTText: the empty _MonNameSentToText holds an open box for 189
+  -- frames before the line itself, which then gets 80 + 128.
+  { id = "sent_blank", frames = 189, cue = "clear" },
+  { id = "sent_text", frames = 208 },
+  -- OTSendsText1's two pages, the second carrying its trailing `ld c, 14`.
+  { id = "ot_sends_a", frames = 80 },
+  { id = "ot_sends_b", frames = 94 },
+  -- OTBidsFarewell's two.
+  { id = "farewell_a", frames = 80 },
+  { id = "farewell_b", frames = 80 },
+  -- GetTrademonSFX, then TubeToPlayer2 waits its 92 BEFORE the pan (the
+  -- mirror of the send, where the wait comes after).
+  { id = "get_wait", frames = 92, cue = "get_sfx" },
+  { id = "get_pan_a", frames = 40 },
+  { id = "get_pan_b", frames = 40 },
+  { id = "get_pan_c", frames = 48 },
+  { id = "get_hold", frames = 128 },
+  -- EnterLinkTube again, then DropBall / ExitLinkTube.
+  { id = "tube_in2", frames = 40, cue = "tube" },
+  { id = "tube_hold2", frames = 80 },
+  { id = "tube_out", frames = 40, cue = "drop" },
+  { id = "ball_wait", frames = 56 },
+  -- ShowGetmonData, then Poof's 16.
+  { id = "getmon_poof", frames = 16, cue = "show_get" },
+  -- FrontpicScrollStart brings the stats window back up for Wait80.
+  { id = "getmon_hold", frames = 80 },
+  { id = "take_care", frames = 80 },
+}
+
+-- Which unrolled pan position a beat starts at, and which way it moves.  The
+-- send pans forward across the 256, the get pans back: TubeToPlayer3/4/5
+-- SUBTRACT 2 a frame, starting from the wrap.
+local PAN = {
+  send_pan_a = { base = 0x00, step = TradeAnim.PAN_STEP },
+  send_pan_b = { base = 0x50, step = TradeAnim.PAN_STEP },
+  send_pan_c = { base = 0xa0, step = TradeAnim.PAN_STEP },
+  send_wait = { base = 0x100, step = 0 },
+  send_hold = { base = 0x100, step = 0 },
+  get_wait = { base = 0x100, step = 0 },
+  get_pan_a = { base = 0x100, step = -TradeAnim.PAN_STEP },
+  get_pan_b = { base = 0xb0, step = -TradeAnim.PAN_STEP },
+  get_pan_c = { base = 0x60, step = -TradeAnim.PAN_STEP },
+  get_hold = { base = 0x00, step = 0 },
+}
+
+-- The beats that print a line, and the text label each one prints.  The empty
+-- _MonNameSentToText is not here: it draws an open box and nothing else, which
+-- is what `sent_blank` having no entry means.
+TradeAnim.TEXT = {
+  sent_text = "_MonWasSentToText",
+  ot_sends_a = "_ForYourMonSendsText",
+  ot_sends_b = "_OTSendsText",
+  farewell_a = "_BidsFarewellToMonText",
+  farewell_b = "_MonNameBidsFarewellText",
+  take_care = "_TakeGoodCareOfMonText",
+}
+
+TradeAnim.TOTAL = 0
+for _, beat in ipairs(TradeAnim.SCRIPT) do
+  TradeAnim.TOTAL = TradeAnim.TOTAL + beat.frames
+end
+
+-- The beat a frame index (0-based) lands in, and how far into it that is.
+-- Past the end answers the last beat, so a caller that overruns by a frame
+-- draws the final picture rather than nothing.
+function TradeAnim.beatAt(frame)
+  frame = math.max(0, math.floor(tonumber(frame) or 0))
+  local start = 0
+  for index, beat in ipairs(TradeAnim.SCRIPT) do
+    if frame < start + beat.frames then
+      return beat, frame - start, index
+    end
+    start = start + beat.frames
+  end
+  local last = TradeAnim.SCRIPT[#TradeAnim.SCRIPT]
+  return last, last.frames, #TradeAnim.SCRIPT
+end
+
+-- The frame index a beat starts on, for tests and for a caller that wants to
+-- jump.
+function TradeAnim.startOf(id)
+  local start = 0
+  for _, beat in ipairs(TradeAnim.SCRIPT) do
+    if beat.id == id then return start end
+    start = start + beat.frames
+  end
+  return nil
+end
+
+-- hSCX during the two scrolls that bring the give-mon panel home.  Both the
+-- background and the window are $88 out and close at 4 a frame.
+function TradeAnim.givemonOffset(t)
+  return math.max(0, TradeAnim.GIVEMON_SCROLL - TradeAnim.SCROLL_STEP * t)
+end
+
+-- hSCX for the link tube.  Entering, it closes from $a0; leaving, it opens
+-- back out to $a0.  The tube's tilemap sits at hlcoord 8, 2, so the drawing
+-- side subtracts this from that x -- SCX scrolls the BACKGROUND, and a
+-- positive value moves the picture LEFT.
+function TradeAnim.tubeOffset(id, t)
+  local step = TradeAnim.SCROLL_STEP * t
+  if id == "tube_out" then
+    return math.min(TradeAnim.TUBE_SCROLL, step)
+  end
+  return math.max(0, TradeAnim.TUBE_SCROLL - step)
+end
+
+-- How far along the 256-pixel Game Boy scene the window is, unrolled: 0 is the
+-- player's Game Boy at the left, 256 is the other one.  nil for a beat that is
+-- not part of a pan.
+function TradeAnim.pan(id, t)
+  local row = PAN[id]
+  if not row then return nil end
+  local value = row.base + row.step * (tonumber(t) or 0)
+  if value < 0 then return 0 end
+  if value > TradeAnim.PAN_TOTAL then return TradeAnim.PAN_TOTAL end
+  return value
+end
+
+-- The trademon object's two ends, in screen pixels: TubeToOT1's
+-- `depixel 5, 11, 4, 0` and TubeToPlayer1's `depixel 9, 18, 4, 4`, OAM-adjusted.
+local ICON_NEAR_X, ICON_NEAR_Y = 80, 28
+local ICON_FAR_X, ICON_FAR_Y = 140, 60
+-- .MoveRight's `cp $94` / .MoveLeft's `cp $58` and .MoveDown's `cp $4c` /
+-- .MoveUp's `cp $2c`, one pixel a frame.
+local ICON_RUN = ICON_FAR_X - ICON_NEAR_X
+local ICON_DROP = ICON_FAR_Y - ICON_NEAR_Y
+
+-- .WaitTimer1 and .WaitTimer2 hold it still for their $80 apiece.
+local ICON_PARKED = {
+  send_pan_a = true, send_pan_b = true, send_pan_c = true,
+  get_pan_a = true, get_pan_b = true, get_pan_c = true,
+}
+
+-- Where TradeAnim_AnimateTrademonInTube has the icon and its bubble on a pan
+-- beat, or nil once .done_move_down / .WaitTimer2 zero SPRITEANIMSTRUCT_INDEX.
+function TradeAnim.tubeIcon(id, t)
+  t = math.max(0, math.floor(tonumber(t) or 0))
+  if ICON_PARKED[id] then return ICON_NEAR_X, ICON_NEAR_Y end
+  if id == "send_wait" then
+    local run = math.min(ICON_RUN, t)
+    local drop = math.min(ICON_DROP, math.max(0, t - ICON_RUN))
+    return ICON_NEAR_X + run, ICON_NEAR_Y + drop
+  end
+  if id == "get_wait" then
+    local drop = math.min(ICON_DROP, t)
+    local run = math.min(ICON_RUN, math.max(0, t - ICON_DROP))
+    return ICON_FAR_X - run, ICON_FAR_Y - drop
+  end
+  return nil
+end
+
+-- The two trademon records TradeAnimation reads, built the way DoNPCTrade
+-- fills them: the PLAYER's is the mon that just left the party (its own DVs,
+-- OT and ID, under the player's name as sender), the OT's is the row's mon
+-- (the row's OT name doubling as the sender).  Called with the two records
+-- NpcTrade.perform answered, so the given mon is the one that walked in, not
+-- whatever now sits in that party slot.
+function TradeAnim.records(data, save, row, given, received)
+  local pokemon = (data and data.pokemon) or {}
+  local player = (save and save.player) or {}
+  local function speciesOf(id)
+    local def = id and pokemon[id]
+    return {
+      species = id,
+      name = (def and def.name) or id or "?",
+      dex = (def and def.dex) or 0,
+    }
+  end
+  local give = speciesOf(given and given.species)
+  local get = speciesOf(received and received.species
+    or (row and row.get))
+  give.senderName = player.name or "GOLD"
+  give.otName = (given and (given.otName or given.ot)) or give.senderName
+  give.id = (given and given.otId) or player.id or 0
+  give.shiny = given and given.shiny or false
+  -- The DVs ride along because TradeAnim_GetFrontpic runs `predef
+  -- GetUnownLetter` before GetBaseData (engine/movie/trade_animation.asm:
+  -- 795-804): without them a traded Unown draws as letter A.  unownLetter is
+  -- carried too, since Unown.monLetter prefers the stored form.
+  give.dvs = given and given.dvs
+  give.unownLetter = given and given.unownLetter
+  get.senderName = (row and row.otName) or (received and received.otName) or "?"
+  get.otName = get.senderName
+  get.id = (received and received.otId) or (row and row.otId) or 0
+  get.shiny = received and received.shiny or false
+  get.dvs = received and received.dvs
+  get.unownLetter = received and received.unownLetter
+  return give, get
+end
+
+return TradeAnim