<?phpnamespace App\Entities\Objects;use App\Entities\GameObject;use App\Gfx\Gfx;/** * Act 3 Robotnik, one state machine per zone, ported from the SMS object code * (doObjectCode_boss_* in the disassembly). ROM speeds are in px/frame at 60Hz: x60 for px/s, x3600 for px/s². * Positions are the original ones: object X = block X * 32, Y = block Y * 32, the camera is locked on the * 256x192 arena given to `_7c8c`. * * think() returns events for the GameObjectManager: * ['part', BossPart] spawn a projectile / bomb * ['hurt'] the player touched the boss without attacking * ['hit'] the player hit the boss (bounce: Y speed reversed, X speed cleared) * ['knockback', vx] Sky Base: Sonic pushed back from the glass * ['explosion', x, y] * ['carry', x, y] Scrap Brain lift: Sonic is moved by the lift * ['complete'] act finished without a capsule (Scrap Brain, Sky Base) */class Boss extends GameObject{ public const GREEN_HILL = 0x12; public const BRIDGE = 0x48; public const JUNGLE = 0x2C; public const LABYRINTH = 0x49; public const SCRAP_BRAIN = 0x22; public const SKY_BASE = 0x4A; // frames of BossSprites (tools/bosssprites.py), drawn at the object's X / Y like the ROM sprite layouts private const PREFIX = [ self::GREEN_HILL => 'gh', self::JUNGLE => 'jungle', self::BRIDGE => 'bridge', self::LABYRINTH => 'lab', self::SCRAP_BRAIN => 'sb', self::SKY_BASE => 'sky', ]; // $D216 / 18: the _7922 layout of the hit egg mobile (+1 facing right), +2 once defeated private const HIT_LAYOUT = [self::GREEN_HILL => 1, self::JUNGLE => 5, self::BRIDGE => 9, self::LABYRINTH => 9]; // _77be: $D2B1 = $18 after a hit, decremented every other frame (_1f06): no contact meanwhile private const HIT_FRAMES = 0x30; // Robotnik running (_a9b7 / _ba28): frames 3, 4, 5, 4 of _baf9, each shown duration + 1 frames private const RUN_FRAMES = [[3, 9], [4, 8], [5, 9], [4, 8]]; // Green Hill (_724b): command lists ($72A1...), 0 = loop to the index that follows private const GH_LISTS = [ 0xA1 => [1, 0, 0], 0xA4 => [2, 0, 0], 0xA7 => [3, 0, 0], 0xAA => [5, 0, 0], 0xAD => [9, 0, 0], 0xB0 => [7, 7, 7, 7, 4, 4, 4, 4, 4, 8, 0, 0], 0xBC => [11, 11, 11, 11, 6, 6, 6, 6, 6, 8, 0, 0], ]; // _72c8: facing right (layout _730a) for each command private const GH_RIGHT = [0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0]; // $7261: Y speed (/256 px/frame) bobbing the ship, indexed by the frame counter $13 private const GH_SINE = [0, 20, 40, 40, 60, 60, 60, 80, 80, 80, 80, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 80, 80, 80, 80, 60, 60, 60, 40, 40, 20, 0, 0, -20, -40, -40, -60, -60, -60, -80, -80, -80, -80, -100, -100, -100, -100, -100, -100, -100, -100, -100, -100, -80, -80, -80, -80, -60, -60, -60, -40, -40, -20, 0]; private const F = 60.0; // px/frame -> px/s private const A = 3600.0; // px/frame² -> px/s² private const FRAME = 1 / 60; private const ARENA = [ self::GREEN_HILL => [0x760, 0xE8], self::BRIDGE => [0x3A0, 0x300], self::JUNGLE => [0x1F0, 0x48], self::LABYRINTH => [0x2D0, 0x290], self::SCRAP_BRAIN => [0x530, 0x220], self::SKY_BASE => [0x350, 0x120], ]; private int $kind; private bool $started = false; private int $hits = 0; private int $maxHits = 8; private float $invulnerable = 0; private string $phase = 'idle'; private int $frames = 0; // frames in the current phase private float $clock = 0; private int $step = 0; private float $bob = 0; private int $chargeDir = -1; private int $dipCounter = 0; /** Scrap Brain: Robotnik leaves on the lift but the object stays to drive the lift. */ private bool $doctorShown = true; private float $homeX; private float $homeY; private bool $gone = false; private bool $liftVisible = false; private float $liftY = 0; /** Top of our real view: the Scrap Brain lift carries Sonic until he has left it (the ROM screen is lower). */ public float $viewTop = -INF; /** Original camera (top-left of the 256x192 screen), set every frame by the object manager. */ public ?array $romCamera = null; /** Scrap Brain flight: RAM_LEVEL_LEFT follows the camera X, the screen can't go back left. */ private float $fleeLeft = 0x340; private float $carriedY = 0; private array $events = []; private array $player = ['x' => 0, 'y' => 0, 'width' => 0, 'height' => 0]; private float $playerVx = 0; // position at the previous 60Hz frame: the 120Hz display interpolates between the two private float $prevX = 0; private float $prevY = 0; private bool $facingRight = false; private int $tickCount = 0; private ?string $layout = null; /** _79fa exhaust flame [frame, x offset] / Labyrinth thruster frame */ private ?array $flame = null; private ?string $thrust = null; private float $drawDy = 0; private string $ghList = 'A1'; private int $ghIndex = 0; private int $ghTimer = 0; private int $ghFlags = 0; private int $skyPose = 0; public function __construct(Gfx $sdl, int $type, string $name, int $tileX, int $tileY) { parent::__construct($sdl, $type, $name, $tileX * 32, $tileY * 32, 32, 28); $this->kind = $type; $this->tilesetName = BossSprites::SHEET; if ($type === self::BRIDGE) { $this->width = 0x1E; } if ($type === self::GREEN_HILL) { $this->y -= 8; } elseif ($type === self::SCRAP_BRAIN || $type === self::SKY_BASE) { $this->width = 0x1E; $this->height = 0x2F; if ($type === self::SKY_BASE) { $this->x += 8; $this->y += 16; $this->maxHits = 12; } } $this->homeX = $this->x; $this->homeY = $this->y; $this->prevX = $this->x; $this->prevY = $this->y; $this->visible = $type !== self::BRIDGE && $type !== self::LABYRINTH; $this->updateLayout(); } public static function supports(int $type): bool { return isset(self::ARENA[$type]); } public function isStarted(): bool { return $this->started; } public function isGone(): bool { return $this->gone; } /** Scrap Brain: Sonic has been carried off the screen by the lift. */ public function hidesPlayer(): bool { return $this->kind === self::SCRAP_BRAIN && $this->phase === 'done'; } public function isDefeated(): bool { return $this->hits >= $this->maxHits; } public function getHits(): int { return $this->hits; } public function hasFled(): bool { return $this->phase === 'defeated' && $this->frames > 320; } /** True while the player's controls are taken away (Scrap Brain lift). */ public function isCutscene(): bool { return ($this->kind === self::SCRAP_BRAIN && in_array($this->phase, ['liftUp', 'liftDown', 'carry', 'done'], true)) || ($this->kind === self::SKY_BASE && $this->phase === 'teleport' && !$this->gone); } /** SMS camera position (top-left of the 256x192 view) while the boss is fought. */ public function getCameraLock(): ?array { // Sky Base: the screen stays locked on the teleporter after Robotnik has gone (_7c8c) if ($this->kind === self::SKY_BASE && $this->phase === 'teleport') return [0x550, 0x120]; if (!$this->started || $this->gone) return null; // Scrap Brain flight: LEFT = camera X every frame, RIGHT = $540, the camera goes to Y = $220 if ($this->kind === self::SCRAP_BRAIN && $this->phase === 'flee') return [$this->fleeLeft, 0x220, 0x540]; // Sky Base: 15 frames after the glass broke the level right becomes $550, Sonic runs after Robotnik if ($this->kind === self::SKY_BASE && $this->phase === 'escape' && $this->frames >= 0x0F) { return [self::ARENA[self::SKY_BASE][0], self::ARENA[self::SKY_BASE][1], 0x550]; } return self::ARENA[$this->kind]; } /** Horizontal range the player is kept in during the fight. */ public function getPlayerBounds(): ?array { $lock = $this->getCameraLock(); if ($lock === null) return null; return [$lock[0], ($lock[2] ?? $lock[0]) + 256 - 24]; } public function think(float $deltaTime, array $playerRect, float $playerVx, bool $attacking): array { $this->events = []; if (!$this->active || $this->gone) return []; $this->player = $playerRect; $this->playerVx = $playerVx; if (!$this->started && $this->shouldStart()) { $this->started = true; $this->phase = 'start'; $this->frames = 0; } if (!$this->started) return []; $this->clock += $deltaTime; while ($this->clock >= self::FRAME) { $this->clock -= self::FRAME; $this->prevX = $this->x; $this->prevY = $this->y; $this->tick($attacking); // teleports (Bridge / Labyrinth spots) are not interpolated if (abs($this->x - $this->prevX) > 16 || abs($this->y - $this->prevY) > 16) { $this->prevX = $this->x; $this->prevY = $this->y; } } $this->updateLayout(); return $this->events; } private function shouldStart(): bool { $px = $this->player['x']; $py = $this->player['y']; return match ($this->kind) { // Jungle: Sonic has climbed to the top of the waterfall self::JUNGLE => $py < 0xE0 && $px > 0x1F0 - 64, // the object only runs inside its activity window (_31e6): Sonic is in the corridor of the lift, // not anywhere right of $340 (he starts far below) self::SCRAP_BRAIN => $this->romCamera !== null && ActivityWindow::contains($this->kind, $this->homeX, $this->homeY, $this->romCamera), default => $px >= self::ARENA[$this->kind][0] - 32 && $px <= self::ARENA[$this->kind][0] + 256 && $py >= self::ARENA[$this->kind][1] - 64 && $py <= self::ARENA[$this->kind][1] + 192, }; } /** One 60Hz frame. */ private function tick(bool $attacking): void { $this->frames++; $this->tickCount++; if ($this->invulnerable > 0) $this->invulnerable -= self::FRAME; if ($this->isDefeated() && $this->kind !== self::SKY_BASE && $this->kind !== self::SCRAP_BRAIN) { $this->defeatSequence(); return; } match ($this->kind) { self::GREEN_HILL => $this->greenHill(), self::JUNGLE => $this->jungle(), self::BRIDGE => $this->bridge(), self::LABYRINTH => $this->labyrinth(), self::SCRAP_BRAIN => $this->scrapBrain(), self::SKY_BASE => $this->skyBase($attacking), }; $this->x += $this->vx / self::F; $this->y += $this->vy / self::F; if ($this->kind !== self::SCRAP_BRAIN && $this->kind !== self::SKY_BASE && $this->visible) { $this->checkContact($attacking); } } /** * `_77be`: box X+8..X+width, Y+$0C..Y+height. Touching it hurts Sonic unless he is jumping / rolling; * no contact for 48 frames after a hit (the hit layout is shown meanwhile). */ private function checkContact(bool $attacking): void { $box = ['x' => $this->x + 8, 'y' => $this->y + 0x0C, 'width' => $this->width - 8, 'height' => $this->height - 0x0C]; if ($this->invulnerable > 0 || !Mechanism::overlaps($box, $this->player)) return; if (!$attacking) { $this->events[] = ['hurt']; return; } $this->hits++; $this->invulnerable = self::HIT_FRAMES * self::FRAME; $this->events[] = ['hit']; } /** After the last hit: 10 explosions 24 frames apart, sinks for 48 frames, then flies off to the right. */ private function defeatSequence(): void { if ($this->phase !== 'defeated') { $this->phase = 'defeated'; $this->frames = 0; $this->vx = $this->vy = 0; } $f = $this->frames; if ($f <= 240) { $this->vx = $this->vy = 0; if ($f % 24 === 0) { $this->events[] = ['explosion', $this->x + mt_rand(0, 32), $this->y + mt_rand(0, 28)]; } } elseif ($f <= 288) { $this->vy = 0x20 / 256 * self::F; } elseif ($f <= 320) { $this->vy = 0; } else { if ($f === 321) { $this->events[] = ['levelMusic']; // $D2EE = $5A: the level music comes back } $this->vx = 3 * self::F; $this->vy = -0xA0 / 256 * self::F; // _77be: removed once off the right of the screen (X >= camera X + 256), the screen is unlocked if ($this->x >= self::ARENA[$this->kind][0] + 256) { $this->gone = true; $this->visible = false; $this->active = false; } } $this->x += $this->vx / self::F; $this->y += $this->vy / self::F; } // ------------------------------------------------------------------ Green Hill // doObjectCode_boss_greenHill: a list of commands ($14/$15), the next one every 16 frames ($12, $13). // 1 / 2: fly left / right at 1 px/frame bobbing (sine $7261) to the side of the arena, then the next list // (left, right, left, then down); 3 / 5: down at $60/256 to the ground; 7 / 11: wait; 4 / 6: charge at // 4 px/frame for 80 frames; 8 / 9: back up to the top at 1 px/frame. private function greenHill(): void { [$left, $top] = self::ARENA[self::GREEN_HILL]; $vy = self::GH_SINE[$this->ghTimer & 0x3F] / 256; $list = self::GH_LISTS[hexdec($this->ghList)]; while (($cmd = $list[$this->ghIndex] ?? 0) === 0) { $this->ghIndex = $list[$this->ghIndex + 1] ?? 0; } $vx = 0; switch ($cmd) { case 1: $vx = -1; if ($this->x <= $left + 6) { $this->ghIndex = 0; $this->ghList = ($this->ghFlags & 2) ? 'A7' : 'A4'; $this->ghFlags ^= 2; } break; case 2: $vx = 1; if ($this->x > $left + 0xE0) { $this->ghIndex = 0; $this->ghList = ($this->ghFlags & 4) ? 'AA' : 'A1'; $this->ghFlags ^= 4; } break; case 3: case 5: $vy = 0x60 / 256; if ($this->y > $top + 0x74) { $this->ghIndex = 0; $this->ghList = $cmd === 3 ? 'B0' : 'BC'; } break; case 4: $vx = 4; break; case 6: $vx = -4; break; case 8: $this->ghList = 'AD'; $this->ghIndex = 0; $this->ghTimer = 0; break; case 9: $vy = -1; if ($this->y <= $top + 0x1A) { $this->ghIndex = 0; $this->ghList = 'A1'; } break; } $this->facingRight = (bool)self::GH_RIGHT[$cmd]; $this->vx = $vx * self::F; $this->vy = $vy * self::F; if ((++$this->ghTimer & 0x0F) === 0) { $this->ghIndex++; } } private function nextStep(): void { $this->step++; $this->frames = 0; } // ------------------------------------------------------------------ Jungle // Comes down to y=$58, flies 1px/frame between x=$21C and x=$2AA; at each end dips 39px and drops a bomb. private function jungle(): void { if ($this->phase === 'start') { $this->vy = 0x80 / 256 * self::F; if ($this->y >= 0x58) { $this->vy = 0; $this->phase = 'left'; } return; } if ($this->phase === 'left' || $this->phase === 'right') { $this->vy = 0; $this->vx = $this->phase === 'left' ? -self::F : self::F; $this->facingRight = $this->phase === 'right'; if (($this->phase === 'left' && $this->x < 0x21C) || ($this->phase === 'right' && $this->x >= 0x2AA)) { $this->step = $this->phase === 'left' ? 1 : 0; $this->phase = 'dip'; $this->dipCounter = 0x67; } return; } // dip: counter $67 -> 0 $this->vx = 0; $c = --$this->dipCounter; if ($c <= 0) { $this->vy = 0; $this->phase = $this->step ? 'right' : 'left'; } elseif ($c >= 0x40) { $this->vy = self::F; } elseif ($c < 0x28) { $this->vy = -self::F; } else { $this->vy = 0; if ($c === 0x34) { // object $2B at (X+$0B, Y+$30) $bomb = new BossPart($this->sdl, $this->x + 0x0B + 8, $this->y + 0x30 + 8, BossPart::frames2('jungle_bomb', 2), 5 / 60); $bomb->explodeFrames = BossPart::frames2('jungle_boom', 3, 1); $bomb->setTileset(BossSprites::SHEET); $bomb->gravity = 0x20 / 256 * self::A; $bomb->maxFall = 3 * self::F; $bomb->landOnFloor = true; $bomb->friction = 2 / 256 * self::A; $bomb->fuse = (0x64 + mt_rand(0, 0x3F)) * 2 / 60; $this->events[] = ['part', $bomb]; } } } // ------------------------------------------------------------------ Bridge // Rises out of the water at one of two places, waits 100 frames, fires 3 cannonballs toward Sonic, sinks. private function bridge(): void { switch ($this->phase) { case 'start': case 'sunk': [$this->x, $this->y] = mt_rand(0, 1) ? [0x3D4, 0x3C0] : [0x444, 0x3C0]; $this->visible = true; $this->phase = 'rise'; break; case 'rise': $this->vy = -0x80 / 256 * self::F; if ($this->y <= 0x380) { $this->vy = 0; $this->phase = 'wait'; $this->frames = 0; } break; case 'wait': $this->vy = 0; if ($this->frames >= 0x64) { $this->fireBridge(); $this->phase = 'sink'; } break; case 'sink': $this->vy = 0x80 / 256 * self::F; if ($this->y > 0x3C0) { $this->vy = 0; $this->phase = 'sunk'; } break; } } private function fireBridge(): void { $left = $this->player['x'] < $this->x; $offsetX = $left ? 0 : 0x20; $speeds = [[0x140, -0x400], [0x1A0, -0x280], [0x240, -0x100]]; foreach ($speeds as [$sx, $sy]) { // bullet $0D: 8x16 sprite at its X / Y, gravity $10/256 px/frame² $ball = (new BossPart($this->sdl, $this->x + $offsetX + 4, $this->y - 10 + 8, BossPart::frames2('bridge_bullet', 2), 1 / 60)) ->withVelocity(($left ? -$sx : $sx) / 256 * self::F, $sy / 256 * self::F); $ball->gravity = 0x10 / 256 * self::A; $ball->setTileset(BossSprites::SHEET); $ball->life = 4; $this->events[] = ['part', $ball]; } $this->events[] = ['sfx', 0x01]; } // ------------------------------------------------------------------ Labyrinth // Three spots in turn: from below (fires two shots) or from above (drops a homing mine). private function labyrinth(): void { $spots = [[0x33C, 0x360, 0x328, 0x360], [0x2EC, 0x260, 0x2B0, 0x260], [0x38C, 0x260, 0x2B0, 0x260]]; [$sx, $sy, $stopY, $backY] = $spots[$this->step]; switch ($this->phase) { case 'start': [$this->x, $this->y] = [$sx, $sy]; $this->visible = true; $this->phase = 'in'; break; case 'in': $this->vy = ($this->step === 0 ? -0x80 : 0x80) / 256 * self::F; if (($this->step === 0 && $this->y <= $stopY) || ($this->step !== 0 && $this->y >= $stopY)) { $this->y = $stopY; $this->vy = 0; $this->phase = 'wait'; $this->frames = 0; } break; case 'wait': $this->vy = 0; if ($this->frames >= 0x64) { if ($this->step === 0) { foreach ([[4, -1], [0x20, 1]] as [$ox, $dir]) { // bullets $0D, gravity 4/256 px/frame² $shot = (new BossPart($this->sdl, $this->x + $ox + 4, $this->y - 6 + 8, BossPart::frames2('lab_bullet', 2), 1 / 60)) ->withVelocity($dir * self::F, -self::F); $shot->gravity = 4 / 256 * self::A; $shot->setTileset(BossSprites::SHEET); $shot->life = 4; $this->events[] = ['part', $shot]; } $this->events[] = ['sfx', 0x01]; } else { // homing torpedo $2F at (X+$0F, Y+$22) $mine = new BossPart($this->sdl, $this->x + 0x0F + 8, $this->y + 0x22 + 8, BossPart::frames2('lab_torpedo_l', 2), 4 / 60); $mine->rightFrames = BossPart::frames2('lab_torpedo_r', 2); $mine->setTileset(BossSprites::SHEET); $mine->homing = [2 / 256 * self::A, self::F, $this->player['x'] + 12 < $this->x + 8 ? -1 : 1]; $mine->life = 8; $this->events[] = ['part', $mine]; } $this->phase = 'out'; } break; case 'out': $this->vy = ($this->step === 0 ? 0x80 : -0x80) / 256 * self::F; if (($this->step === 0 && $this->y >= $backY) || ($this->step !== 0 && $this->y <= $backY)) { $this->vy = 0; $this->step = ($this->step + 1) % 3; $this->phase = 'start'; } break; } } // ------------------------------------------------------------------ Scrap Brain // No fight: Robotnik runs ahead of Sonic to the lift at x=$5A0 and escapes; the lift then comes back for Sonic. private function scrapBrain(): void { $heroX = $this->player['x']; switch ($this->phase) { case 'start': $this->phase = 'flee'; // no break case 'flee': if ($this->romCamera !== null) $this->fleeLeft = max($this->fleeLeft, min(0x540, $this->romCamera[0])); $close = $this->x - $heroX < 0x40 && $this->playerVx >= 0; $this->vx = ($close ? $this->playerVx / self::F : -0.5) * self::F + self::F; $this->liftVisible = true; $this->liftY = 0x2AF; if ($this->x >= 0x5A0) { $this->x = 0x5A0; $this->vx = 0; $this->events[] = ['knockback', 0]; // Sonic's X speed cleared, the joypad is ignored $this->phase = 'liftUp'; $this->frames = 0; } break; case 'liftUp': $this->vx = 0; $this->y = 0x280 - $this->frames; $this->liftY = 0x2AF - $this->frames; if (($this->frames & 0x1F) === 0x0F) $this->events[] = ['sfx', 0x19]; // $C0 frames: off the 256x192 screen; our taller view: on until he has left it too if ($this->frames >= 0xC0 && ($this->y + 0x30 <= $this->viewTop || $this->y <= 0)) { $this->doctorShown = false; $this->phase = 'liftDown'; $this->carriedY = $this->liftY; $this->frames = 0; } break; case 'liftDown': $this->liftY = $this->carriedY + $this->frames; if (($this->frames & 0x1F) === 0x0F) $this->events[] = ['sfx', 0x19]; if ($this->liftY >= 0x2AF) { $this->liftY = 0x2AF; $this->phase = 'waitHero'; $this->frames = 0; } break; case 'waitHero': // $596 < Sonic X <= $5C0, Sonic Y >= $28D (down in the lift shaft) if ($heroX > 0x596 && $heroX <= 0x5C0 && $this->player['y'] >= 0x28D) { $this->phase = 'carry'; $this->frames = 0; } break; case 'carry': $this->liftY = 0x2AF - $this->frames; $this->events[] = ['carry', 0x5A0, $this->liftY]; if (($this->frames & 0x1F) === 0x0F) $this->events[] = ['sfx', 0x19]; // $C0 frames take Sonic above the 256x192 screen; our taller view: on until he has left it too if ($this->frames >= 0xC0 && ($this->liftY + 0x10 <= $this->viewTop || $this->liftY <= 0)) { $this->events[] = ['music', 'actcomplete']; $this->phase = 'done'; $this->carriedY = $this->liftY; $this->events[] = ['complete']; } break; case 'done': // Sonic is put off the screen (camera X + 256), the empty lift goes back down $this->events[] = ['carry', 0x5A0, $this->carriedY]; $this->liftY = min(0x2AF, $this->liftY + 1); if ($this->liftY < 0x2AF && ((int)$this->liftY & 0x1F) === 0x0F) $this->events[] = ['sfx', 0x19]; break; } $this->vy = 0; if (in_array($this->phase, ['liftUp', 'liftDown', 'waitHero', 'carry', 'done'], true)) { $this->vx = 0; } } // ------------------------------------------------------------------ Sky Base // Robotnik behind the glass: hops and fires every ~6s; 12 hits on the glass (from x>=$410) break it, // then he runs off to the right. private function skyBase(bool $attacking): void { if ($this->hits < $this->maxHits) { if ($this->invulnerable <= 0 && $attacking && $this->player['x'] >= 0x410) { $this->hits++; $this->invulnerable = self::HIT_FRAMES * self::FRAME; $this->events[] = ['knockback', -3 * self::F]; $this->events[] = ['sfx', 0x01]; } switch ($this->phase) { case 'start': case 'idle': $this->phase = 'idle'; $this->vx = $this->vy = 0; // every 8 frames: stands / leans (_ba1c pose 0 / 1) in turn, still from the $1C-th step if ($this->tickCount % 8 === 0) { $this->skyPose = intdiv($this->frames, 8) < 0x1C ? 1 - $this->skyPose : 0; } if ($this->frames >= 40 * 8) { $this->phase = 'jump'; $this->frames = 0; $this->x = $this->homeX + 4; $this->vy = -0x1C0 / 256 * self::F; } break; case 'jump': $this->vy = min(2 * self::F, $this->vy + 0x0E / 256 * self::A / self::F); if ($this->vy > 0 && $this->y >= $this->homeY) { $this->y = $this->homeY; $this->vy = 0; $this->x = $this->homeX; $this->phase = 'fire'; $this->frames = 0; // _b9d5: the electric ball $47, one at a time if ($this->skyBall === null || !$this->skyBall->isActive()) { $shot = new BossPart($this->sdl, 0x420 + 8, 0x12F + 8, RomSprites::ELECTRIC_BALL, 1 / 30); $shot->setTileset(RomSprites::SHEET); $shot->electricWait = 0xC8 / 60; $shot->life = 12; $this->skyBall = $shot; $this->events[] = ['part', $shot]; } } break; case 'fire': if ($this->frames >= 0x12) { $this->phase = 'idle'; $this->frames = 0; } break; } return; } if ($this->phase === 'teleport') { $this->skyBaseTeleport(); return; } if ($this->phase !== 'escape') { $this->phase = 'escape'; $this->frames = 0; $this->skyBall?->setActive(false); $this->vy = 0; $this->events[] = ['explosion', 0x420, 0x12F]; $this->events[] = ['sfx', 0x21]; $this->events[] = ['music', 'scrapbrain']; } // runs to the right ahead of Sonic, with gravity, jumping when blocked $close = $this->x - $this->player['x'] < 0x40 && $this->playerVx >= 0; $this->vx = $this->x >= 0x5E0 ? 0 : (($close ? $this->playerVx / self::F : -0.5) + 1) * self::F; $this->vy = min(2 * self::F, $this->vy + 0x0E / 256 * self::A / self::F); if ($this->level) { $feetX = (int)($this->x + $this->width / 2); $floor = $this->level->findSurfaceY($feetX, (int)($this->y + $this->height - 4), 12); if ($floor !== null && $this->vy >= 0 && $this->y + $this->height >= $floor - 1) { $this->y = $floor - $this->height; $this->vy = 0; if ($this->level->isSolidAt((int)($this->x + $this->width + 4), (int)($this->y + $this->height - 8))) { $this->vy = -0x280 / 256 * self::F; } } } // on the teleporter block ($49) at $5E0: he stops there, the screen is locked on ($550, $120) if ($this->x >= 0x5E0 && $this->vy == 0) { $this->phase = 'teleport'; $this->frames = 0; $this->x = 0x5E0; $this->y = 0x160; $this->vx = 0; } } /** * _b821 bit 3: the joypad is ignored; every 8 frames he swaps between pose 0 and pose 1 (2px lower, _b99f), * from step $2C the teleport frame _bb77, at step $30 he has gone and 64 frames later the object is * removed: Sonic can then take the teleporter (block behaviour 11, $FF = to the end of the game). */ private function skyBaseTeleport(): void { $this->vx = $this->vy = 0; $step = intdiv($this->frames, 8); if ($step >= 0x30) { $this->doctorShown = false; if ($this->frames >= 0x30 * 8 + 0x40) { $this->gone = true; $this->visible = false; } } } // _b821: the broken glass, 15 patches of 2x2 tiles ($BA45, tools/skybaseglass.py), one a frame private const GLASS_X = [0x420, 0x430, 0x440]; private const GLASS_Y = [0x160, 0x170, 0x180, 0x190, 0x1A0]; private ?BossPart $skyBall = null; private function renderSkyBase(float $cameraX, float $cameraY): void { $renderer = $this->sdl->getRenderer()->getRenderer(); $broken = $this->hits >= $this->maxHits; if ($broken) { $texture = $this->sdl->getTextures('skyglass')[0]['texture']; $count = $this->phase === 'escape' ? min(15, $this->frames) : 0; for ($i = 0; $i < $count; $i++) { $src = new \SDL_Rect; [$src->x, $src->y, $src->w, $src->h] = [$i * 16, 0, 16, 16]; $dst = new \SDL_Rect; [$dst->x, $dst->y, $dst->w, $dst->h] = [(int)round(self::GLASS_X[$i % 3] - $cameraX), (int)round(self::GLASS_Y[intdiv($i, 3)] - $cameraY), 16, 16]; \SDL_RenderCopy($renderer, $texture, $src, $dst); } return; } // _ba31 / _ba3b: Robotnik's weapon at ($430, $1A0), raised while he fires $frame = RomSprites::SKY_WEAPON[$this->phase === 'fire' ? 1 : 0]; $src = new \SDL_Rect; [$src->x, $src->y, $src->w, $src->h] = $frame; $dst = new \SDL_Rect; [$dst->x, $dst->y, $dst->w, $dst->h] = [(int)round(0x430 - $cameraX), (int)round(0x1A0 + 1 - $cameraY), 16, 16]; \SDL_RenderCopy($renderer, $this->sdl->getTextures(RomSprites::SHEET)[0]['texture'], $src, $dst); } private function runFrame(): int { $t = $this->tickCount % 34; foreach (self::RUN_FRAMES as [$frame, $duration]) { if ($t < $duration) return $frame; $t -= $duration; } return 3; } /** Sprite layout of this frame (null: nothing drawn), with the flame of _79fa / the Labyrinth thruster. */ private function updateLayout(): void { $p = self::PREFIX[$this->kind]; $this->flame = null; $this->thrust = null; $this->drawDy = 0; if ($this->kind === self::SCRAP_BRAIN) { $this->layout = $this->phase === 'flee' ? $p . '_f' . $this->runFrame() : $p . '_f0'; return; } if ($this->kind === self::SKY_BASE) { // _b99f: pose 0 = frame 0, pose 1 = frame 1 2px lower; firing: frame 1 7px lower; jumping: frame 2 $this->layout = match ($this->phase) { 'jump' => $p . '_f2', 'fire' => $p . '_f1', 'escape' => $this->vx != 0 ? $p . '_f' . $this->runFrame() : $p . '_f' . (intdiv($this->tickCount, 8) % 2), 'teleport' => intdiv($this->frames, 8) >= 0x2C ? $p . '_end' : $p . '_f' . (intdiv($this->frames, 8) % 2), default => $p . '_f' . $this->skyPose, }; $this->drawDy = match ($this->phase) { 'fire' => 7, 'jump', 'escape' => 0, 'teleport' => intdiv($this->frames, 8) % 2 ? 2 : 0, default => $this->skyPose ? 2 : 0, }; return; } $base = self::HIT_LAYOUT[$this->kind]; $right = $this->facingRight ? 1 : 0; if ($this->phase === 'defeated') { // flies off with the normal ship facing right (_7922) $this->layout = $p . '_egg' . ($this->frames > 320 ? 0 : $base + 2 + $right); } elseif ($this->invulnerable > 0) { $this->layout = $p . '_egg' . ($base + $right); } elseif ($this->kind === self::GREEN_HILL || $this->kind === self::JUNGLE) { $this->layout = $p . ($right ? '_right' : '_left'); } else { $this->layout = $p . '_body'; } // _79fa: on even frames while moving, tile 0/2 (4/6 going right) at X+$28 (X-8 going right), Y+$10 if (($this->kind === self::GREEN_HILL || $this->kind === self::JUNGLE) && $this->vx != 0 && $this->tickCount % 2 === 0) { $k = ($this->tickCount & 2) ? 1 : 0; $this->flame = $this->vx > 0 ? [$p . '_flame' . ($k + 2), -8] : [$p . '_flame' . $k, 0x28]; } if ($this->kind === self::LABYRINTH && $this->vy < 0 && !$this->isDefeated()) { $this->thrust = $p . '_thrust' . (($this->tickCount & 2) ? 1 : 0); } } private function blitFrame(string $name, float $x, float $y, float $cameraX, float $cameraY, bool $flash = false): void { $rect = BossSprites::FRAMES[$name] ?? null; if ($rect === null) return; $src = new \SDL_Rect; [$src->x, $src->y, $src->w, $src->h] = $rect; $dst = new \SDL_Rect; // the VDP draws the sprites one line lower [$dst->x, $dst->y, $dst->w, $dst->h] = [(int)round($x - $cameraX), (int)round($y + 1 - $cameraY), $rect[2], $rect[3]]; $texture = $this->sdl->getTextures(BossSprites::SHEET . ($flash ? '-flash' : ''))[0]['texture']; \SDL_RenderCopy($this->sdl->getRenderer()->getRenderer(), $texture, $src, $dst); } public function render(float $cameraX, float $cameraY): void { if ($this->objectType === self::SKY_BASE) { $this->renderSkyBase($cameraX, $cameraY); } if ($this->liftVisible) { // _a9c0 at ($5A0, $2AF - $11) $this->blitFrame('sb_lift', 0x5A0, $this->liftY, $cameraX, $cameraY); } if (!$this->visible || !$this->doctorShown || $this->layout === null) return; $alpha = min(1, $this->clock / self::FRAME); $x = $this->prevX + ($this->x - $this->prevX) * $alpha; $y = $this->prevY + ($this->y - $this->prevY) * $alpha; // _1f06: after a hit sprite colour 15 (the outlines) is white while $D2B1 is odd (not in Sky Base, // which flashes a tile colour, nor under the water of Labyrinth) $d2b1 = (int)ceil($this->invulnerable / self::FRAME / 2); $flash = $d2b1 % 2 === 1 && $this->kind !== self::SKY_BASE && $this->kind !== self::LABYRINTH; $this->blitFrame($this->layout, $x, $y + $this->drawDy, $cameraX, $cameraY, $flash); if ($this->flame !== null) { $this->blitFrame($this->flame[0], $x + $this->flame[1], $y + 0x10, $cameraX, $cameraY); } if ($this->thrust !== null) { $this->blitFrame($this->thrust, $x + 0x10, $y + 0x30, $cameraX, $cameraY); } }}