Super Mario All-Stars — PC Port

A native Windows and Android version of Super Mario All-Stars (SNES) with a launcher, true widescreen, re-anchored HUDs, display options, cheats, level select, achievements, a sound test and a music player. It contains no game data: it runs from your own ROM (Super Mario All-Stars (USA).sfc, CRC32 925637C7); no game starts without it.

Building

Requirements: Windows 10/11, Visual Studio 2022 (C++ workload) and CMake 3.20+. No other libraries are needed (Direct3D 11, Direct2D, XAudio2, XInput and DirectInput come with Windows).

build.bat

The program is written to build\Release\SuperMarioAllStars.exe.

Android

The same code builds for Android (android/), as the Mickey & Donald Collection's does: SDL2 2.32.10 compiled from source for the window, sound and controllers, OpenGL ES 3.0 for the picture. You need the Android SDK with NDK 28.2 and CMake 3.31.6 (both from the SDK manager) and JDK 17 or later. The SDL2 source belongs in third_party/SDL2-2.32.10-src (android/fetch_sdl.ps1 downloads and checks it), then:

cd android
gradlew assembleDebug

The APK ends up in android/app/build/outputs/apk/debug/ (64-bit ARM phones and tablets, Android 6.0 or later, and the x86_64 emulator). Release builds are signed when android/keystore.properties names a keystore (storeFile, storePassword, keyAlias, keyPassword), as the Disney collection's are.

Running

Put the ROM next to the executable, in a roms folder beside it, or in any parent folder up to three levels up; the location is remembered in rompath.txt. Without it the launcher's cards say ROM not found and what is needed, and a ROM copied in while the launcher is open is picked up within a second. Another version or dump of All-Stars runs too, its file name shown in amber on the cards: widescreen, cheats and the level select are tuned for the USA version.

To start a game directly, give SuperMarioAllStars.exe the argument --game smb1, --game smbll, --game smb2 or --game smb3 (for example in a shortcut).

Battery saves go to saves\smas.srm, save states to saves\, screenshots to screenshots\, settings to smas_port.ini. Files are written in full before they replace the old ones, so a full disk can't leave a truncated save (you are told the save failed instead). Save states carry a checksum: a damaged one is refused rather than loaded. They also keep the widescreen state, so a state loads exactly as it was saved, and one saved at a narrower width (or by an older version) brings in the enemies of the wider view. If the graphics driver resets (a driver update or crash), the picture comes back by itself and the game keeps running.

On Android

Install the APK (Android asks you to allow installing apps from the place you opened it). On the first start the launcher's card says ROM not found: tap it, pick Super Mario All-Stars (USA).sfc (or a .smc) in the file picker, and it is copied into the app. A ROM can also be put in the app's folder Android/data/com.darhkfox.allstars/files (or a roms folder there) with a computer.

• Touch: an SNES pad over the game: the D-pad bottom left, A B X Y bottom right, L and R at the sides, Select and Start bottom centre, Menu top left, and (when they're switched on and achievements are off) rewind and fast forward top right. Tap a game's card to choose it, tap it again to play; in the menus tap a row to use it, drag to scroll, and the button top right goes back.
• Controllers and keyboards work as on Windows (the same bindings); the on-screen controls hide while one is in use (Options → Controls → On-Screen Controls: While Touching, Always or Never, and their opacity).
• Back opens and closes the menu, as Esc does.
• The picture fills the screen (Aspect Ratio: Auto), with the same filters and colour settings. The window settings, VSync, Black Frame Insertion, High Frame Rate and slang shaders are Windows only.
• Saves, states and settings are kept in the app's own storage; screenshots go to Android/data/com.darhkfox.allstars/files/screenshots. Leaving the app saves the game's progress.

Launcher

The program opens on a launcher, laid out like the Mickey & Donald Collection's, over a night-blue sky with twinkling stars and a checkerboard floor after the All-Stars title screen. By default it shows one Super Mario All-Stars card with a live preview of the cartridge's title: choosing it starts the cartridge as it is, at its own title and game select (--game allstars starts it directly). Below are buttons for Options, Achievements, Music Player, Credits and Quit.

Options → Launcher Shows → The Four Games gives one card per game instead (Super Mario Bros., The Lost Levels, Super Mario Bros. 2, Super Mario Bros. 3), each with a live attract-mode preview of that game and the chosen card's sound playing. Each preview is its own console run through the All-Stars game select into the game's title, out of sight while it starts. Choosing a card resets the console and takes it through the All-Stars menu to that game's save files (behind a short black loading screen), where you pick the file as usual. The launcher remembers the last game chosen.

Controls

	Keyboard	Joypad (Xbox layout; PlayStation, Switch Pro and USB/SNES pads supported)
D-pad	Arrow keys	D-pad / left stick
B / A / Y / X	Z / X / A / S	bottom / right / left / top face buttons
L / R	Q / W	LB / RB
Start	Enter	Menu/Start
Menu	Esc or Right Shift (Select)	View/Select
Game's Select button	Menu → Press Select In Game	left stick press
Save / load state	F5 / F8
Fast forward	Tab (hold)	RT (hold)
Rewind	Backspace (hold)	LT (hold)
Fullscreen	F11 or Alt+Enter
Launcher: choose / play / quit	Arrow keys / Enter / Esc	D-pad / A / B
Screenshot	F12

Hold Rewind to go back through roughly the last minute of play (at twice the game's speed), then let go to carry on from there; game progress the game has saved is never undone. Rewind and fast forward can each be switched off under Menu → Controls.

Everything can be rebound under Menu → Controls (keyboard and pad, both players). Each controller keeps its pad number while others are plugged in or out, and gets it back when it reconnects, so the players never swap controllers. Select opens the menu and backs out of it. The games only need their own Select button for the All-Stars save menu (pause, then Select). If you'd rather have it on Select, set Controls → Select Button to "Tap: Game Select - Hold: Menu".

Menu

The pause menu is a dark panel over the dimmed game, tinted in the running game's colour (red SMB1, green Lost Levels, purple SMB2, orange SMB3; the launcher's buttons gold). Every row explains itself in the line at the bottom. It is laid out as:

• Resume and Press Select In Game.
• Save states — the slot (with the time it was saved, or "Empty"), Save State, Load State.
• Game — Level Select, Cheats, Achievements (earned / total), Sound Select, Music Player, Options (Display, Graphics, Colour, Audio, Controls, fast forward and rewind, achievements on or off), Credits.
• System — Take Screenshot, Reset Game (back to the game's save files), Return to Launcher, Quit to Desktop (the last three ask first).

Short notices (state saved, screenshot taken) appear in the top-right corner, or at the bottom while the menu is open. An unlocked achievement shows a banner at the top of the screen.

What each page holds:

• Level Select — every level listed under its world, the game chosen at the top (it starts on the one being played); picking one asks first. For SMB2 a Character choice (Mario, Luigi, Toad, Peach) sets who plays it, picked for you on the character select. Any world and level of all four games: SMB1, The Lost Levels (worlds 1–9 and A–D), SMB2 (1-1 to 7-2) and SMB3 (every world map, numbered level and fortress, and the levels without a numbered panel: each world's airship and the Coin Ship, World 2's desert and pyramid, World 5's second fortress and tower, World 7's Piranha Plant levels, World 8's tanks, battleship, hand traps, super tanks and Bowser's castle. Those are entered from 1-1's panel with the level swapped as it loads, the map left as it was). The chosen level comes up directly: the game is run to it behind a short black loading screen, launched from the game-select screen when needed (a running game is reset first, so unsaved progress is lost). In SMB3 it is a new game in that world, with the world as play would have left it: the levels numbered before the chosen one are cleared, and where the map's paths lead to it on foot, the fortresses before it too, with their locks open (World 1's 1-5: 1-1 to 1-4, the fortress and its lock). Where the way leads through a map pipe (World 4 on), only the numbered levels are. Clearing the level marks its panel as usual; losing a life there sends Mario back to the world's start, from where the cleared part of the map is open.
• Cheats (per game) — SMB1/Lost Levels: infinite lives, star power, invincibility, always fire, infinite time, moon jump. SMB2: infinite lives, full health, star power, four hearts, super jump, float like Peach. SMB3: infinite lives, star power, infinite flight, full P-meter, infinite time, always raccoon, stocked item box, invincibility.
• Sound Select — classic sound test: any music number of any game's sound bank plus the three sound-effect channels.
• Music Player — named track lists for the menu, SMB1 & Lost Levels, SMB2, SMB3 courses and SMB3 world maps, with repeat / play-next and an 8-channel level display. It plays on its own sound chip, so the game is untouched.
• Display — windowed / borderless / exclusive fullscreen, monitor selection, window size, aspect ratio (4:3, 16:10, 16:9, 21:9, auto), pixel shape (CRT 8:7 or square), scaling (fit, integer, stretch; integer uses whole multiples both ways, with CRT pixels as close to 8:7 as that allows), HUD re-anchoring, widescreen enemy behaviour, dimmed sides in SMB2's wrap-around climbing areas, side-border style, VSync (turn it off for G-SYNC / FreeSync), black frame insertion (a black refresh after each game frame for sharper motion, like a CRT; needs VSync and a 120, 180 or 240 Hz display, and the picture gets darker), High Frame Rate (on 100 Hz and faster displays the refreshes between the game's 60 frames show in-between pictures: each line is drawn again with the layers' scroll and the sprites part of the way back to the last frame, cuts and jumps left as they are; the game still runs at 60 and the picture is a frame later; at a rate that isn't a multiple of 60, like 100, 144 or 165 Hz, each in-between is drawn at the moment its refresh shows it, so motion stays even; with VSync off, on G-SYNC / FreeSync, they're presented at the display's rate), FPS counter.
• Graphics — nearest, sharp bilinear, bilinear, CRT scanlines, CRT aperture grille and LCD grid filters, effect strength, screen curvature, sprite-limit removal. Slang Shader runs a RetroArch slang preset (.slangp) in place of the filter, through librashader (librashader.dll next to the exe, MPL-2.0, third_party/librashader; without it the game runs on the built-in filters). Presets are listed from a shaders folder next to the exe, with their shader files beside them, e.g. the libretro slang-shaders collection; the colour settings don't apply to them. Seven CRT presets are bundled (third_party/slang-shaders, copied to shaders\ by the build): crt-lottes (public domain), crt-geom, crt-royale, crt-easymode, crt-aperture, zfast-crt and crt-pi (GPL, LICENSE-GPL-2.0.txt), unmodified from libretro/slang-shaders with only the files they use; see third_party/slang-shaders/README.txt. Some presets assume a 4:3 picture and can stretch or frame oddly in widescreen.
• Colour — colour profiles (Original, Vivid, CRT Television, Muted, Greyscale, Sepia, Pocket, Virtual, Night, Console Accurate), brightness, contrast, saturation, gamma, colour temperature, colour-vision assist (protanopia / deuteranopia / tritanopia), and Mario's Colours / Luigi's Colours: alternate outfits for each brother (Super Mario Bros. and The Lost Levels), kept by each in co-op whichever is the game's player.
• Audio — volume, latency, mute when unfocused.
• Credits — where to find the author (YouTube, Reddit, GitHub; each opens in your browser).
• CO-OP GAME on the title screens of Super Mario Bros., The Lost Levels and Super Mario Bros. 3: a third choice under 1 PLAYER GAME / 2 PLAYER GAME (MARIO GAME / LUIGI GAME; in SMB3 a fourth, under BATTLE GAME), picked with the game's own cursor. It starts a one-player game with co-op on (Luigi on controller 2); the game's own choices start without it. The choice sets the option below. In SMB1 and The Lost Levels the status bar's name reads MARIO & LUIGI during a co-op game, and the level card (WORLD 1-1) shows both brothers' heads; in SMB3 the status bar (in levels and on the map) shows a combined M L badge, x and the shared lives, and the map's WORLD box shows both brothers. A co-op game starts (or continues) with at least 10 lives, as the brothers share them.
• Options → Multiplayer → Two-Player Co-op (SMB1, Lost Levels, SMB3) — Mario and Luigi play at the same time in Super Mario Bros. and The Lost Levels. Controller 1 has the character the game was started with (Mario, or Luigi in a Lost Levels Luigi game), controller 2 the other (by default the second controller, or I J K L, N jump, H run). The game's own player code runs a second time each frame with the other player's variables swapped in, so both move, jump, bump blocks, stomp enemies, get hurt, take power-ups and throw fireballs as the game's player does; in The Lost Levels each has his own physics and sprites (Luigi jumps higher and slides more). Objects that meet the player in their own code (lifts, springboards, firebars, hammers) run a second time for the other player, so both ride lifts, bounce on springs and get burnt. The world is shared. Whoever is further right moves the screen and the other is held at its left edge; the screen waits while the one behind is at that edge and still playing. Left idle (controller untouched for 3 seconds) while the other plays, he is brought to where the other last stood on the floor (or swims), can't be hurt by enemies, and is brought back rather than lost if he drops into a hole, until his controller is used again. He walks through the game's scenes too: the pipe intro (as before 1-2), and at the flag he slides down the pole if he reaches it and follows into the castle. Whoever takes Bowser's axe has the victory scene (Toad thanks him); the other comes along to Toad. The score is one shared score; after a game over, Continue goes on with the character the game was started with. Either can take a pipe, a vine or the flag: the game goes on with him and the other comes along after it. Lives are shared: a player who dies while the other plays on comes back beside him once that player is on his feet (on solid ground where there is some), small and blinking, for one life; with none left he sits out until the next area. When a player dies while the other plays on, his death tune plays and the area's music then carries on from where it paused (not from its start). Save states and rewind keep both players (see src/game/smb1coop.cpp).
• Super Mario Bros. 3 co-op (the same option; see src/game/smb3coop.cpp) — Luigi on controller 2, run through the game's own player code with his own variables: his own form and power-ups, stomps, hits, the star, flying, picking up the goal card. Each enemy or item deals with whichever player is nearer (enemies' fireballs and hammers too; a kicked shell hits either, as in the original), or with the one playing while the other is left idle. Luigi throws his own fireballs and hammers, carries shells and slides down slopes. The screen follows the point between the two (both directions, and up for a flyer) and its edges hold them in view (the whole wide view in widescreen). A player whose controller has been left alone for 3 seconds rests: the screen follows the other, and the resting one is brought to where the other last stood when the screen leaves him behind (an auto-scroll's edge included), and nothing hurts him until his controller is used again (pits, lava and the time limit still count). Lives are shared. Either can die while the other plays on, as in SMB1's co-op: if Mario dies, Luigi takes over as the game's player (controllers and colours follow each brother). The one who died plays his death tune and jump, then comes back where the other stands, small and blinking. Either can take a pipe or a door, or grab the goal card or a Koopaling's wand: the other goes along, into the next area in the form he had. The map has Mario only; the level start card reads MARIO START! / LUIGI START!.
• Co-op speed — the game's player code runs twice a frame in co-op, which slowed busy scenes down on the console's own clock, so with co-op on (SMB1, The Lost Levels, SMB3) the emulated CPU runs at twice its speed (Snes::setCpuFast); the PPU, DMA and sound chip keep their timing. One-player games keep the console's timing exactly.

Achievements

82 achievements: 20 for Super Mario Bros., 19 for The Lost Levels, 20 for SMB2, 21 for SMB3, and two for the whole collection. Menu → Achievements lists them by game with the date each was earned. Achievements with several steps show progress, for example "3 / 8" castles; the "defeat 100 enemies" ones count across all your play. A few are secrets: they are marked "Secret:" in their description. They are saved in achievements.ini next to the settings, and they stay earned.

Fair play. While achievements are on, cheats, level select, fast forward and rewind are off. Options → Achievements switches them off, and those features come back. A run counts from a game started from the launcher, or from Reset Game, with achievements on. A save state remembers whether its run counts, so loading one from a cheated run doesn't earn anything. The first start explains this once.

Game	Achievements
Super Mario Bros.	Wrong Castle (World 1 castle), Castle Crasher (every castle, 0/8), Thank You Mario! (8-4), The Long Way Round (finish from 1-1 without a warp zone), Shortcut (a warp zone), Top of the Pole (5000 at the flagpole), Fireworks Show, Coin Heaven (a vine up to a hidden area), Pocket Change (100 coins), Not a Scratch (a castle without getting hurt), Star Power (5 enemies with one Starman), Lives to Spare (20 lives), Player Two (finish a level as Luigi), Six Figures (100,000 points), Fired Up (a Fire Flower), Express to World 8 (warp straight there), Bro Down (a Hammer Bro), Barbecue Bowser (Bowser by fireballs), Goomba Stomper (100 enemies, counted over all your play), and a secret: Speedy Plumber (finish 1-1 with 300 or more on the clock)
The Lost Levels	Same Old Story, Lost No More (castles of worlds 1-8, 0/8), Peach Found, Secret World 9, The Very End (World D castle), Warp Ahead, Lofty Leap, Celebration, Cloud Nine, Coin Purse, Lost but Unharmed, Shooting Star, Hot Stuff (a Fire Flower), Brother Beater (a Hammer Bro), Green Machine (a castle in the LUIGI GAME), Bowser Flambé (Bowser by fireballs), Lost Legion (100 enemies), and two secrets: Wrong Way! (get sent back by a warp zone), No Time to Lose (finish 1-1 with 300 or more on the clock)
Super Mario Bros. 2	One for each boss: Bomb Squad (Mouser), Snake Charmer (Tryclyde), Cat and Mouser, Cool Customer (Fryguy), Rock Lobster (Clawgrip), Heads Will Roll and Wake Up! (Wart). Also Dream Team (clear a level with each hero, 0/4), Untouchable (a level without getting hurt), Jackpot (a life from the Bonus Chance), Full of Heart (four hearts), Mushroom Hunter, Starman, Down the Jar (a warp), POW! (three enemies at once), Extra Lives (10 lives), Through the Door (Subspace), Phanto Menace (wake a Phanto), Egg Return (defeat Birdo), Veggie Tales (100 enemies)
Super Mario Bros. 3	Royal Rescue (a king's wand), All the King's Wands (0/7), Dark Land (World 8), The End of Bowser, Warp Whistle, Frog Prince, Tanooki Time, Hammer Time, Wings of Wonder (P-Wing), Full House (three matching cards), Coin Hoard (100 coins), Packed Inventory (28 items), Toad's Treasure, Seven Figures (1,000,000 points in one game; a game over resets the score, saves keep it), Lives Galore (99 lives), Stone Cold (a Tanooki statue), If the Shoe Fits (Kuribo's Shoe), Lullaby (a Music Box on the map), Rock Breaker (a Hammer on a map rock), Koopa Krusher (100 enemies), and a secret: Five-Up (three Star cards at the goal)
Collection	All-Star (finish all four games, 0/4), Completionist (every other achievement)

In SMB1 co-op, Player Two counts when Luigi takes the axe or rides the flagpole down (as the game's player, or kept aside and already on the pole as the flag scene starts), and Not a Scratch is lost when either player is hurt.

Frame pacing

The games run at 60.1 frames per second. With VSync on, the frame loop waits on the display's vertical blank itself, so driver settings that force VSync off or use "Fast Sync" don't cause uneven frames. On 60, 120 or 240 Hz displays every frame lasts the same number of refreshes. With VSync off, frames are presented at the game's own rate, which is what G-SYNC / FreeSync displays want.

How widescreen works

The port emulates the SNES hardware and renders each scanline wider than the original 256 pixels. Per-game logic (in src/game/) makes the extra area show real content:

• level tiles come from the game's own streamed tilemaps; columns the game has not produced yet are never shown as garbage;
• parallax scenery that the game streams only just ahead of the screen is rebuilt from the game's scenery data;
• the status bar is split and pinned to the screen edges;
• sprites in the margins get correct 9-bit positions, and with Widescreen Enemies: Active In Full View enemies spawn just outside the wide view and stay active across it, instead of popping in or freezing at the old 4:3 edges. What's in the margins then behaves as on the screen: the games skip things for objects off their 4:3 screen, and those tests use the wide view instead (fireballs and kicked shells hit enemies there, enemies there fire, throw and spit, and their projectiles aren't erased at the old edge).

Per game:

• SMB1 / The Lost Levels — the screen can't scroll back, and the game stops the player at the left edge of its 256-px screen. The extra width is shown ahead of the player first, as far as the game has always built the level, with room for an enemy to stand on it (72 px). The rest (20 px at 16:9, up to 128 px at 21:9) shows the level just passed on the left, and the player can walk back into it, right up to the display edge: the game's own wall at its screen edge moves out to there, and his collisions with enemies and fireballs there are worked out in full precision (the game's are 8-bit and screen-relative). Left of where an area begins (a level start, a pipe exit) the game has built nothing, so the margin there continues the area's own floor, ceiling, hills and clouds (an area that opens with a wall, like 1-2, carries on the wall, and one that opens raised, like the castles' first steps, carries on the raised floor, with sky above where the rest of the area is a bridge, as in 2-3 and 7-3; the hills carry on as their panorama loops, or mirrored about the level's start where its loop doesn't join up); the player still stops at the area's real start, as on the console. The level is built exactly when the console builds it, because level objects act when they're built (scroll locks, warp zones, frenzies, castle loops). The game's logic is untouched: only its sprite drawing is told that objects in the margin are visible. With Widescreen Enemies: Original Timing fireballs, hammers and enemies behave, collide and disappear exactly as on the console; with Active In Full View the player's fireballs fly on into the margin and hit enemies there (they were erased at the 4:3 edge), Hammer Bros there throw, and their hammers stay in the view (also with the player in the left margin, where they reach him and hurt him). A coin block hit in the left margin bounces and shows its coin there. With Original Timing, the game's own screen is pixel-identical to 4:3; this is checked automatically in 1-1, 1-2, 1-4 and 2-2. The hill and cloud panoramas are drawn from the game's background maps in RAM. The "BONUS" Mario picture in the cloud bonus areas (2-1's vine) leaves through the margin as it scrolls by: it used to vanish once it had left the 4:3 part, the sky on screen then too plain to keep its layer recognised. Night levels have no clouds, and their hills are a fixed 512 px map the hardware wraps, drawn as such (3-1's and 6-2's used to be cut at the edges of the 4:3 part). The castle mazes keep their margins when they loop: after a wrong turn sends Mario back, the walls in the margins carry on the ones in the 4:3 part (4-4's showed other parts of the castle's backdrop). The level next to the start, where the loop leaves the camera, is shown too, not left blank. An area entered further on (a pipe's way out) carries its own background on, mirrored, left of where it starts (8-4's castle showed the water level's ruins there). With Active In Full View, enemies (groups of Goombas and Koopas and Bowser's flames included) arrive from just outside the wide view, the game's own distances measured from its edge. That is further out than the game has built the level, so a walking enemy spawned there waits, out of sight, until the level under it is built (it would otherwise fall through the unbuilt part, or end up inside the bricks built around it). A group of enemies that had to wait for room (the wide view keeps enemies longer), or that comes in range as an area loads mid-level (out of a pipe), never starts inside a block or where the level isn't built yet (1-1's last two Goombas used to end up in the end staircase after the coin room). A single walker or swimmer that had to wait for one of the five enemy slots starts just beyond the view's edge rather than at its own place, which by then is in view (2-2's Blooper popped in), on the same kind of ground; where there is none clear there (5-1's Koopa, at a block), and for hopping Paratroopas, it starts in its place. A jumpspring always gets one of the enemy slots: with them all taken it went to the slot the flagpole's flag and power-ups use, and vanished (2-1's spring before its wall, leaving the player stuck on its tiles); now an enemy behind the 4:3 screen makes room, or the spring moves to the first slot that frees up. A vine stays until it leaves the view (the game erased it once off its 256 px screen, so it vanished in the margin as Mario climbed on and the screen moved). Sprites are placed by their objects' true positions, so one that leaves on the right (a kicked shell) can't reappear on the left, and sprites the game hides by moving them off its screen (sparks, fireworks) stay hidden. Enemies that walk off left past where an area began keep to the floor shown there. The status line is split to the corners. The underground coin rooms are shown wide and centred: their brick wall carries on into both margins and the exit pipe is drawn whole, its right half included (checked in every coin room of both games). The short scene before x-2's pipe (the castle, the pipe Mario walks into) is shown wide and centred too, from the moment it fades in: its ground, hills and clouds carry on into both margins (it used to be 4:3). So is the card between levels (WORLD 1-2, the lives left, the level's picture): its grey fills the display and the status line is split to the corners as in play. Leaving play (a pipe, a death, a level's end, a vine), the picture changes once the screen has gone dark. Once Bowser is beaten, the walk to Toad (or the princess) and the messages stay wide, eased to the centre of the display (the messages are centred on the game's screen); before, the view dropped to 4:3 as the message came up. 8-4's ending shows its message once (it is on the cloud layer, which the margins used to repeat) and the room whole to the right. Bowser is drawn whole as he comes into view: All-Stars' own Bowser drawing made half his sprites 8x8 while they were off its 256 px screen, which cut off his shell in the margin. Firebars are drawn in the margin too: with Original Timing they stay still there until they reach the 4:3 screen, as the console leaves them; with Active In Full View they turn (and burn) across the whole view.

• SMB2 — enemies spawn across the whole wide view, including when an area starts (the game's check against spawning on top of the player compared positions modulo 256 px, which refused almost every spawn ahead at 21:9). Levels are kept whole in RAM, so the margins are drawn from the level data with the game's own tile tables (checked tile-for-tile against the game's output); night skies come from the game's own star map. Near an area's start the slower hills and clouds show more than the game has laid out. The clouds are a loop of four screens (shuffled each time an area is entered), so the loop carries on; hills that repeat do the same. Other scenery repeats its first screen where its ends join up, and is mirrored about the area's start where they don't, so no cloud or hill is ever cut off. All 8 cloud orders and every area's start and end were checked at 21:9. Jar interiors are shown wide and centred, the jar standing in its area's scenery: the screen's background carries on into the margins (repeated where its ends join up, mirrored where they don't), only what runs on from the screen's edge, so a moon or a lone cloud isn't doubled. Vertical areas (one screen wide; the game wraps them around) and single-page areas are shown 4:3, centred. Both switch while the screen is dark. Enemies are drawn across the whole view, and Albatosses and diving Beezos arrive from its edges. The life meter moves to the edge, and the pause box (with its undimmed window) is centred in the view. Subspace, and the fades into and out of it, stay 4:3; the end of a level switches width once the screen is dark.

• SMB3 — enemies and moving platforms spawn across the whole wide view and move as soon as they are in it. On auto-scroll levels, where the scroll speed is known, anything heading into view is kept on the console's timeline: it comes in from the edge of the picture already moving, and is exactly where the 4:3 game would have it from the moment that game spawns it (1-4's drifting platforms cross the gaps at their original times). The game has room for only five level objects at a time, and the wider view shows more of them: objects still waiting to come into view don't hold a place, what the 4:3 game has at that moment always gets one, and objects that find no room come in as soon as there is. An object about to come into view takes a place from one out of sight that the 4:3 game has already removed (behind the player) or that is further out, and the one nearest to coming into view goes first; until then the objects kept behind the player held every place, and those ahead appeared only at the 4:3 spawn point, about 100 px inside the wide picture. Where the console itself is short of room (the tank levels) or the margin behind still shows the objects holding the places (World 7's pipe-plant level), an object can still appear inside the wide picture rather than at its edge. Objects the 4:3 game has always get a place first, on auto-scroll and normal levels alike, taking it from one that only the margins show (one out of sight first) or that the 4:3 game has already removed. Walking enemies simply start where they appear, so they may be further along than on the console. The playfield margins are drawn from the level data in RAM as it was at the frame's vblank, which is what the game's own tilemap shows that frame, so a block an enemy carries off or a coin collected changes on the same frame in the margins as in the 4:3 picture; the status bar stays centred on the screen. Vertical areas show their scenery in the margins. Single-screen rooms are wide too, centred: the boss rooms, the bonus rooms behind pipes, the hammer brothers' and the King's room, with black either side: each is a set piece, and made up from its edges it showed things it doesn't have (a second throne, the hammer brothers' blocks twice). The airships' boss rooms instead carry on: the cabin's log walls and beams as wide as the view, the deck's posts in front of them. The mushroom house keeps its own shape, with black either side, and so does the world map (it stays the wide shape between the map and the levels, the picture never switching to 4:3 and back). The spade game's black surround carries on. The battle game's arena wraps around, so its pipes, platforms and floor carry on off both sides, dimmed (the "Dim Wrap-Around Sides" option), with the backdrop pattern continuing; the round panel between rounds carries its gold border on, undimmed. Objects in the margins are spawned when a level loads, as they would be if they were on screen (two sharing a spot included). A level opens with its circle reaching out to the edges of the wide picture, and the picture goes wide while the screen is still black. A door or pipe that moves the camera without the screen going dark (the World 1 fortress's door) spawns only what the new view shows, not everything between the two places (it used to bring the fortress's hidden Warp Whistle chest out at the door). Levels that scroll a lower band separately (the World 1 fortress's moving floor, the tank levels' ground) keep that band joined to the margins. The level's own controllers (the objects that start, steer and stop auto-scrolling, or switch a level's behaviour, as in the hand-trap and World 4 levels) act exactly when they do at 4:3, however much further the wide view reaches, so the game's camera always follows the console's path. After the goal card the player walks on past the level's end to the edge of the wide picture (at 4:3 he walks 32 px off the screen; the level ends at the same moment either way). On an auto-scroll level, where the view shows past the level's start or end, the player is held at the level's start or end instead of the view's edge, and stands still there (he used to drift past the end and die in the cloud treasure areas while the camera was still on its way). Enemies brought in to fill the margins are set up from the side they come in on.

• SMB2 and SMB3 keep their own camera. In SMB2, at the ends of a level the view stops at the level edge rather than showing space outside the level, so the player can walk right up to the display edge. While the view is held there, the slower background layers are shifted to match it (rounded exactly as the game rounds them), so the parallax stays correct. SMB3's view stays centred on the game's screen, as at 4:3, at a level's start and end too, auto-scroll levels included: the goal area, an airship's end and the boss rooms sit in the middle. The level carries on past its ends: its floor, ceiling or sky as they repeat there (checkered floors stay checkered, a floor's end piece isn't repeated), and the scenery between them, where it reaches the end, mirrored about it, so a slope becomes a hilltop and bushes, posts and hills go on as they look (where the end is plain, it carries on plain, and where it is a wall, as the fortress boss rooms end, it carries on as a wall; where it is a cliff, as 2-2 ends, the ground carries on solid beyond it; where a level ends at a solid wall from top to bottom, as 3-5 and the World 4 tower levels do, the wall carries on, a pipe through it with it; where a platform's own edge is at the level's start, as 3-9's big bolted blocks are, there is open sky beyond rather than a mirrored copy). Plain textures such as dirt carry on unturned; coins and blocks are never shown there, nor anything the level has only once (a pipe's rim, the goal's card frame). Inside a level, a wall the player can't get past (solid all the way down the screen, as the fortresses' sections and boss rooms are walled off) is carried on over what lies beyond it, rather than showing the next part of the level or what moves there; and a room walled in on both sides (the bonus rooms down the pipes in 2-1, 4-5 and 3-9, the last with walls only a block or two thick) is centred on the display. The "COURSE CLEAR!" message hides the layer it is drawn on in the margins (3-7's clouds showed there). SMB3's layer speeds are measured as the level scrolls; a newly measured speed never makes a layer jump.

• SMB3 auto-scroll levels (such as 1-4 and the airships) use the whole wide picture: the player can run ahead to the display's right edge and is pushed by its left edge, exactly as the 4:3 game does with its own screen edges (and is crushed if the scroll pins him against a wall), and enemies there can be stomped (and can hurt). The picture scrolls exactly as steadily as the original: it stays centred on the game's screen, through pauses on the way (the W6 airship, 7-4), to the level's end. Near the start, the player can walk back to the level's beginning (off an airship's stern too, as off any ledge). Objects heading into view are kept on the console's timeline from the first frame, while the scroll is still picking up speed. When 5-9's camera jumps ahead, what only the margins showed of the part left behind goes with it. The pause menu is centred on the display.

• The title screens are wide too:

  • SMB1's and The Lost Levels' title is the start of 1-1 with the logo over it. It is shown centred, as that level would be. When the demo starts scrolling, the view eases back to the level's own layout.

  • SMB2's title and story, and SMB3's title, are pictures drawn 256 px wide. Each layer is carried on into the margins from the picture's edges, line by line.

    • Where a pattern repeats there (red border, stage curtain, checkered floor), the repeat continues.
    • SMB3's hills at the edges are mirrored as far as each hill reaches, so the half-hills become whole groups ending in their own outline.
    • Elsewhere the edge pixel carries on.

  • SMB2's character select is framed by a lattice of diamonds, which carries on over the margins with its colours alternating, as in the frame.

  • SMB2's level cards ("WORLD 1-1") have a blue background with small emblems scattered over it. The margins get the same emblems, read off the card, at the same density. Emblems the card's blank edge columns cut in half are made whole.

  • The select stays wide while the card wipes in over it.

  The game carousel is wide from the moment it starts to appear. The All-Stars title is wide too: the sky and the pale band go on in their colours, and the checkerboard floor carries on in perspective, each row's tiles continued at their width and in their colours (read off the tiles at both screen edges; the floor is symmetric about the middle). The cast stays as drawn. As the title dissolves into the game select (black triangles drawn in ring by ring from the edges in), the margins dissolve with the outermost ring, in its triangles. World maps and other full-screen compositions stay 4:3, with the chosen side-border style.

Development tools

build\Release\smastool.exe is a headless runner/debugger used to reverse-engineer the games (see tools/SMASTOOL.md); findings are documented in docs/re/.

Source layout

Folder	What
src/core/	The SNES: 65C816, SPC700 and DSP, PPU (with the widescreen and high frame rate parts)
src/game/	The four games' widescreen, achievements, cheats, level select and co-op
src/app/	The application, the same on both systems: app.cpp (launcher, game, menu pages, achievements), menus (menu.cpp), launcher, music player, settings, drawn on canvas.h; sys.h for files and paths. Windows: app_win.cpp (window, frame pacing, test modes), video.cpp (Direct3D 11), canvas_d2d.cpp (Direct2D / DirectWrite), audio.cpp (XAudio2), input.cpp (XInput / DirectInput)
src/platform/android/	Android: app_android.cpp (SDL window, events, pacing, ROM picker), video_gles.cpp (OpenGL ES picture and canvas, text from Android's own font), audio_sdl.cpp, input_sdl.cpp, touch.cpp
android/	Gradle project; SmasActivity.java adds the ROM picker and the UI font rasteriser to SDL's activity

The Android build uses SDL2 by Sam Lantinga and contributors (zlib licence, third_party/SDL2-2.32.10-src). The launcher's title is set in Luckiest Guy by Astigmatic (Apache 2.0 licence, third_party/fonts), copied beside the exe and into the Android app.