snivy/MODDING.md

Modding Feed Snivy

Want to add characters or modify existing ones or mod Feed Snivy in general or otherwise want to know how the game works? Here's how.

Animation Format

Feed Snivy uses a semi-proprietary format called ".anm2" for tweened character animations, sourced from a spritesheet. This file format comes from the game The Binding of Isaac: Rebirth (a game I mod on my own time) for animations.

You can either use my own animation editor for that game and this one (recommended), Anm2Ed, or if you have that game on Steam, you can find that game's own proprietary animation editor in that game's Steam folder and then in tools/IsaacAnimationEditor. I can't guarantee the stability or perfect efficacy of either, but Anm2Ed has crash mitigations and autosave (but of course, save often, for whatever you do).

Anm2Ed has slightly more extensions to the base format; in particular, something called "Regions", which allows you to set spritesheet regions (areas in the spritesheet that can be repurposed) to quickly reference in animations; previously, one would have to manually create a perfectly spaced spritesheet and then manually set values; this is no longer the case, so using "Regions" is recommended. For the leanest files, in Anm2Ed, go to Settings -> Configure -> File -> Compatibility, and set it to "Anm2Ed Limited".

My process for making characters is that they're typically comprised of many "cells" (small graphics). I make these cells their own file, and then in the editor, I drag them onto "Spritesheets" and then right click -> merge them, with the "Make Spritesheet Regions" option enabled. Then, right click -> Pack on a spritesheet to optimize it all nice for one big spritesheet atlas with everything in one place. It won't produce a very comprehensible spritesheet, but it works just fine (not my problem). Make sure to save the spritesheets you're using once you're done. You can sort regions around by clicking, holding and moving them around.

If you'd like a quick primer on how to use either program, check either of these videos out. Much of the information is interchangeable between the programs, though both are a little out of date on their current version.

For each "stage" of the character (graphical change), an animation equivalent will be expected. Stages are zero-indexed in this context; so the first stage would be 0. If you have an idle animation and want that for the first, starting stage, you'd need to name the animation "Idle0", for example, and then reference that in character.xml (more on that later). Don't manually input the number for the animation in any file, just put in the first part, "Idle"; the game will handle which stage-animation plays when.

Know that despite Anm2Ed supporting sounds for animations, don't expect these to work in context based on names; use the .xml sound attributes when applicable. You can add sounds for fluff, though.

Resources

There's two folders inside resources; "characters" and "font".

"font" is just a font containing the font used in the selection screen. That's literally it. This technically isn't needed; Dear ImGui has its own font that will be used if this font is missing.

EVERYTHING ELSE is stored inside bespoke character archives (.zips) in the "characters" folder. This has all data associated with characters. Think of characters more as tailored game experiences rather than literally being just the characters. Not only is there the character graphics, but backgrounds, items, parameters, etc. These are intensely customizable to suit whatever experience you'd like (within the confines of the engine, of course).

Feed Snivy uses a collection of XML files to parse data; make sure to brush up on the format. The engine can expect six files in the archive's root:

• areas.xml
• character.xml
• cursor.xml
• dialogue.xml
• items.xml
• menu.xml
• play.xml

(dialogue.xml may or may not be optional; but in future updates I'll make sure of it, for dialogueless characters).

If you're making your own character, your best bet would probably be just to copy the Snivy character and edit it based on your needs, just as a helpful start.

Character

areas.xml

"Areas" refers to the backgrounds of the game. I'd planned for the game to dynamically switch areas based on stage (in case you want a character to become a blob that grows bigger than a city or whatever) but this isn't implemented. I'd just have one entry in here for the game's background.

Areas

TextureRootPath (path)

Working folder/directory of textures the areas will use.

Area

Texture (path)

The file path of the area's texture (background).

Gravity (float)

Gravity the area has; applies to items' velocities per tick.

Friction (float)

Friction of the area; applies to items' velocities when grounded or hitting walls.

AirResistance (float)

Air resistance of the area; applies to items' velocities when airborne.

character.xml

This is the main character file where much of the functionality is stored.

Character

Name (string)

Name of the character; will appear in dialogue, stats, etc.

TextureRootPath (path)

Working folder/directory of where used textures will be contained within.

SoundRootPath (path)

Working folder/directory of where used sounds will be contained within.

Render (path)

Texture for the character's "render" (i.e., a typical full-body display), will show in the Select screen.

Portrait (path)

Texture for the character's "portrait" (i.e., a cropped profile view), will show in the Select screen.

Anm2 (path)

Character's "anm2" file (uses TextureRootPath); should have all the character's animations.

Description (string)

A general description of the character; will show in the Select screen.

Author (string)

The author of the character.

Weight (float, kilograms)

The character's starting weight, in kilograms.

Capacity (float, calories)

The character's starting capacity, in calories.

CapacityMin (float, calories)

The character's minimum capacity, in calories.

CapacityMax (float, calories)

The character's maximum capacity, in calories. Know that max capacity is determined by Capacity * CapacityMaxMultiplier; this determines the max of the "base" capacity.

CapacityMaxMultiplier (float)

Determines the effective max capacity; will be capacity times this number.

CapacityIfOverStuffedOnDigestBonus (float, percent)

When a character is over stuffed (i.e., over base capacity), the character will an additional capacity when digesting based on how overstuffed they are, based on how many calories over the base capacity.

CaloriesToKilogram (float)

Determines how many calories become a kilogram (1 cal -> X kg).

DigestionRate (float, percent/tick)

The base digestion rate, in percent per tick (60 ticks per second).

DigestionRateMin (float, percent/tick)

The minimum digestion rate for the character, in percent per tick.

DigestionRateMax (float, percent/tick)

The maximum digestion rate for the character, in percent per tick.

DigestionTimerMax (int, ticks)

When digesting, the digestion bar will count down, and then when it hits 0, the current calories will be digested. This determines how long this takes, in ticks.

EatSpeed (float)

A multiplier that speeds/slows down the eating animation, at base.

EatSpeedMin (float)

Determines the minimum eating speed multiplier.

EatSpeedMax (float)

Determines the maximum eating speed multiplier.

GurgleChance (float, percent)

Determines how often the character will gurgle (see the Gurgle sounds later) per tick.

GurgleCapacityMultiplier (float)

Per the character's capacity, multiplies the character's gurgle chance based on the percent of capacity filled (based on max capacity). Higher capacity = higher gurgle chance, using this number at maximum.

DialoguePoolID (string)

Determines the character's base dialogue options (for the "How are you feeling?" option in Chat). This is effectively "Stage 1"'s dialogue; each stage should have its own dialogue pool (see later). Also see dialogue.xml for how "Pools" work.

AlternateSpritesheet

Determines the alternate spritesheet of the character, if applicable (in Pokemon terms, the "shiny").

Texture (path)

The alternate spritesheet texture; uses TextureRootPath.

Sound (path)

The sound that will play when the spritesheet is set to alternate (either on new game, or with an item that has IsToggleSpritesheet; see items.xml); uses SoundRootPath.

ID (int)

ID of spritesheet that the alternate spritesheet will replace in the character's .anm2.

ChanceOnNewGame (float, percent)

Chance of rolling for the alternate spritesheet on starting a new game, in percent.

Stages

A "stage" represents each visual change of the character as the weight increases. By default, there's always one stage; adding more here will add additional stages.

Threshold (float, kilograms)

The weight threshold to reach this stage, in kilograms.

DialoguePoolID (string)

Determines the stage's dialogue options (for the "How are you feeling?" option in Chat). Also see dialogue.xml for how "Pools" work.

Animations

The character's animations. Know that a lot of character animations are typically easily played/activated through Dialogue; this is just for animations that aren't reliant on that system. Know that these animations should just be the base name; all animations are expected to have a stage number after them, so don't include the number for these.

Start

The animation name that will first play when starting a new game; used for like a character's introduction.

Idle

The idle animation that the character will regularly return to.

IdleFull

When over capacity, this idle animation will be used instead.

StageUp

When going to a new stage after digestion and going over a stage's threshold, this animation will play.

Animation

The name of the animation to be used for each of these.

Overrides

"Overrides" are the term I use for when some animations will be tweaked by the game engine for effect (blinking and talking being the ones used). There are two elements; "Talk" and "Blink" for this. Typically, how this is handled is that each animation with have an invisible blinking/talking layer (just the graphic that blinks), which will change when called for. Again, review the .anm2 format for what a "layer" is. All that's sourced is just the spritesheet crop in these cases; so don't worry about how the blink/talk layers are set up.

Override

LayerSource (string)

The layer in the animation which will be sourced for the override.

LayerDestination (string)

The layer in the animation which the source will be applied to.

EatAreas

An "eat area" is where the food should be dragged to. I'm pretty much expecting this to only be a mouth for most characters but hey maybe you want the character to also eat through their butt or something. Again, not something that's well-developed at the moment.

EatArea

Null (string)

The null area in the animation where food will be checked for. Again, review the .anm2 format.

Animation (string)

The animation that will play when food is dragged to it.

Event (string)

The event that will be checked for, detrermining the time the food is actually eaten/chewed. Again, review the .anm2 format.

ExpandAreas

The areas which will expand based on capacity percent; usually a stomach. This adds additional scale onto the layer of an animation. This also can scale a null as well. ExpandAreas are presently hardcoded to scale with both capacity and weight at a 50/50 ratio; this could be changed in the future for custom ratios.

ExpandArea

Layer (string)

The layer of the animation that will expand.

Null (string)

The null of the animation that will expand.

ScaleAdd (float, percent)

The scale that will be added at maximum. Know that scale is a percent; a {100, 100} scale is the default and is the normal scale of an animation.

InteractAreas

The areas on a character which can be interacted with; usually for belly rubs, kisses, etc.

InteractArea

Type ("Rub", "Kiss", "Smack")

Three types are presently hard-coded in, but this is kind of hacky and custom support for different interactions may later be added. The cursor will need to be set from the "Tools" in order for each interact area to be activated.

Null (string)

The null in which the interact area can be triggered. Again, review the .anm2 format.

Animation (string)

The animation that will play when the interact area is activated (hovering and clicking).

AnimationFull (string)

The above, but when character is full.

AnimationCursorHover (string)

The animation the cursor will play when hovering over the interact area.

AnimationCursorActive (string)

The animation the cursor will play when holding down click over the interact area.

DialoguePoolID (string)

The dialogue pool which will be drawn from when activating an interact area (see dialogue.xml).

Sound

An interact area can play multiple sounds when interacting; add additional Sound elements to achieve this. Don't worry about repeatedly-loaded sounds; the game will cache them beforehand for efficiency.

Path (path)

The path of the sound being used.

Sounds

Sounds that play in some contexts.

Digest

Sounds that will play when the character begins digesting (digestion bar full).

Gurgle

Ambient sounds that will play randomly based on capacity; see GurgleChance and GurgleCapacityMultiplier above.

Sound (path)

The path of the sound for the specific sound type.

cursor.xml

Determines the cursor appearance and behavior.

TextureRootPath (path)

Working folder/directory of textures the cursor will use.

SoundRootPath (path)

Working folder/directory of sounds the cursor will use.

Anm2 (path)

The anm2 file the cursor will use (depends on TextureRootPath).

Animations

Idle

The cursor's default idle animation.

Hover

The cursor's hover animation, when hovering over an item.

Grab

The cursor's grab animation, when grabbing an item.

Pan

The cursor's pan animation, when panning with middle mouse button.

Zoom

The cursor's zoom animation, when zooming in/out with the mouse wheel.

Return

The cursor's return animation, when holding right click to return an item to the inventory (or to dispose of it if chewed.)

Animation (string)

The animation the cursor will use in these contexts.

Sounds

Know that multiple of these sounds can be defined for each context.

Grab

The sound that will play when grabbing an item.

Release

The sound that will play when releasing an item.

Throw

The sound that will play when throwing an item (releasing when dragging quickly).

Sound (path)

The path of the sound for these respective contexts.

dialogue.xml

The collection of character dialogue; likely the biggest file, depending on your needs.

Dialogue

Entries

Entry

Each bit of dialogue is referred to as an "entry".

ID (string)

Name for the entry. Other entries will rely on this for dialogue chains.

Next (string)

The ID of the entry that will follow after this one. If no Next entry, the text will not continue. Make sure to connect these.

Text (string)

The actual dialogue content of the entry. Should support Unicode, provided the font contains the characters.

Animation (string)

A character animation that will play at the beginning of the dialogue. This may be expanded into the future to allow animations to play dynamically per dialogue index. Again, make sure it's just the base name for the animation, no stage numbers.

Choice

Dialogue can be branching; simply added "Choice" elements into the Entry element.

Next (string)

The dialogue the choice will lead to.

Text (string)

The text of the choice; will appear as a series of buttons in the text window.

Pools

A "pool" of dialogue refers to a collection of entries that can be randomly picked in some contexts.

Pool

ID (string)

The name of the dialogue pool; can be referenced elsewhere.

PoolEntry

ID (string)

The name of the entry; to be added to the pool.

Start

This dialogue will play upon a new game, once its animation has concluded.

Animation (string)

The name of the animation that will be played.

ID (string)

The name of the entry that will be played.

End

The dialogue that will play upon completion of the game (character hitting max stage).

ID (string)

The name of the entry that will be played.

Help

The dialogue that will be play when the player presses the "Help" button in "Chat".

ID (string)

The name of the entry that will be played.

StageUp

Dialogue that will play after a character undergoes a stage up.

PoolID (string)

The name of the pool that entries will be drawn from.

Random

The dialogue that will be play when the player presses the "Let's chat!" button in "Chat".

PoolID (string)

The name of the pool that entries will be drawn from.

Feed

The dialogue that will be play when the user begins holding a food item.

PoolID (string)

The name of the pool that entries will be drawn from.

FeedFull

The dialogue that will be play when the user begins holding a food item, when the character is over capacity.

PoolID (string)

The name of the pool that entries will be drawn from.

Eat

The dialogue that will be play after the character finishes a food item.

PoolID (string)

The name of the pool that entries will be drawn from.

EatFull

The dialogue that will be play after the character finishes a food item, when the character is over capacity.

PoolID (string)

The name of the pool that entries will be drawn from.

Full

The dialogue that will be play when the character is completely full and will deny the user feeding them.

PoolID (string)

The name of the pool that entries will be drawn from.

Throw

The dialogue that will be play when the user throws food.

PoolID (string)

The name of the pool that entries will be drawn from.

LowCapacity

The dialogue that will be play when the character is presented a food item completely over their maximum capacity.

PoolID (string)

The name of the pool that entries will be drawn from.

Digest

The dialogue that will be play when digesting is finished.

PoolID (string)

The name of the pool that entries will be drawn from.

FoodTaken

The dialogue that will play when food is removed from the null area during a character's eating animation.

PoolID (string)

The name of the pool that entries will be drawn from.

FoodTakenFull

The dialogue that will play when food is removed from the null area during a character's eating animation, when the character is over capacity.

PoolID (string)

The name of the pool that entries will be drawn from.

items.xml

Has all items and their parameters, alongside additional behavior.

ItemSchema

TextureRootPath (path)

Working folder/directory of where used textures will be contained within.

SoundRootPath (path)

Working folder/directory of where used sounds will be contained within.

BaseAnm2 (path)

The base anm2 file that items will use. Items can technically have their own .anm2 and animate accordingly, but I haven't tested this much.

Animations

Chew

When items are chewed, play this animation. Items can have chew counts and the animation will adapt accordingly, so be sure to have chew animations for chew counts; 1 chew = Chew1, 2 chew = Chew2, etc.

Animation (string)

The name of the animation. Only the base part ("Chew", usually)

Sounds

The various item sounds. Multiple of the same element can be defined to randomly play from a selection.

Bounce

The sound that will play when an item is bounced (hitting a floor/wall/ceiling with velocity).

Sound (path)

The path to the sound that will play, based on SoundRootPath.

Dispose

The sound that will play when an item is disposed of (when an item has chewed and is right clicked).

Sound (path)

The path to the sound that will play, based on SoundRootPath.

Summon

The sound that will play when an item is spawned (clicking on it in inventory).

Sound (path)

The path to the sound that will play, based on SoundRootPath.

Return

The sound that will play when an item is returned to inventory (right clicking on it in world).

Sound (path)

The path to the sound that will play, based on SoundRootPath.

Categories

The kinds of items present. Will appear in inventory tooltips.

Category

Name (string)

The name of the category.

IsEdible (bool)

Determines if the category of item can be eaten by the character.

Flavors

Item flavors (for food). Honestly have no meaning but flavor text at the moment but whatever.

Flavor

Name (string)

Name of the flavor.

Rarities

Different rarities of item. Shows in inventory and each can have their own drop chance.

Rarity

Name (string)

Name of the rarity.

Chance (float, percent)

Base chance of finding an item, per winning a play of the "play" game. See play.xml for how this is modified.

Sound (path)

Sound that will play when an item is found in the "play" game.

IsHidden (bool)

If true, items with this rarity will not be previewed in the inventory, unlesss possessed. Assumed false if not present.

Items

TextureRootPath (path)

Working folder/directory of where used item textures will be contained within.

ChewCount (int)

Base chew count for items; will be chewed this many times before being erased. Chew count will determine how many calories/digestion bonus/etc. are given per bite (0 chew = all, 2 chew = divided by 3)

SpritesheetID (int)

Item textures will use this spritesheet ID on the base anm2.

QuantityMax (int)

How many items of a type can be possessed at once.

Item

An individual item entry.

Name (string)

The name of the item.

Texture (path)

The texture the item uses; uses TextureRootPath.

Description (string)

Flavor text for the item.

Category (string)

The category the item uses; as defined in Categories.

Rarity (string)

The rarity the item uses; as defined in Rarities.

Anm2 (path; optional)

The custom anm2 the item uses, if needed.

Flavor (string; optional)

The flavor the item uses; as defined in Flavors.

Calories (float; optional)

The amount of calories in an item has (if food).

DigestionBonus (float, percent; optional)

The additional digestion rate in percent the item will give if eaten.

EatSpeedBonus (float; optional)

The additional eat speed multiplier the item will give if eaten.

Gravity (float; optional)

The item's gravity; will use the default gravity if not available.

ChewCount (int; optional)

An item's custom chew count.

IsPlayReward (bool; optional)

The item will be given out when the reward is hit in play (see play.xml)

IsToggleSpritesheet (bool; optional)

When used in the inventory, will toggle the character's spritesheet (in Pokemon terms, toggling normal/shiny palettes).

menu.xml

Determines menu and general UI appearance and behavior.

MenuSchema

SoundRootPath (path)

Working folder/directory of where used sounds will be contained within.

FontRootPath (path)

Working folder/directory of where used fonts will be contained within.

Font (path)

The font the menu will use, based on FontRootPath.

Rounding (float)

The rounding of corners the UI will use.

Sounds

Menu sounds.

Open

Will play when opening a sliding menu panel.

Sound (path)

The sound that will play, based on SoundRootPath.

Close

Will play when closing a sliding menu panel.

Sound (path)

The sound that will play, based on SoundRootPath.

Hover

Will play when hovering over a widget in a menu.

Sound (path)

The sound that will play, based on SoundRootPath.

Select

Will play when clicking on a widget in a menu.

Sound (path)

The sound that will play, based on SoundRootPath.

play.xml

Determines behavior and appearance of the "Play" minigame.

Play

SoundRootPath (path)

Working folder/directory of where used sounds will be contained within.

RewardScore (int)

The play score where a rewarded item will be given (see items.xml)

RewardScoreBonus (float, percent)

Based on the player's score, will add additional bonus to being rewarded items.

RewardGradeBonus (float, percent)

Based on the player's grades for a round of play, will add additional bonus to being rewarded items.

SpeedMin (float, unit/tick)

The beginning/base speed of the bar in the minigame.

SpeedMax (float, unit/tick)

The maximum speed the bar in the minigame can achieve.

SpeedScoreBonus (float)

The additional speed of the bar based on the player's score.

RangeBase (float)

A "range" is each area in the minigame that can be hit. This is the base size of one. Per each grade, it's halved. Range size decreases as minigame progresses.

RangeMin (float)

The minimum size of a range; achievable at high scores.

RangeScoreBonus (float)

Really a negative. The range size will decrease this much per point of score.

EndTimerMax (int)

The period of time between plays of the minigame.

EndTimerFailureMax (int)

When a player fails (no ranges hit), the minigame will pause fo this amount of time, until restarting.

Sounds

Fall

The sound that plays when an item falls from being rewarded.

Sound (path)

The sound that will play, based on SoundRootPath.

ScoreLoss

The sound that plays when the bar goes over the edge and loops, deducting a point.

Sound (path)

The sound that will play, based on SoundRootPath.

HighScore

The sound that plays when the player achieves a high score. Only heard when a high score has been set during the play session.

Sound (path)

The sound that will play, based on SoundRootPath.

HighScoreLoss

The sound that plays when the player has achieved a high score, and then fails.

Sound (path)

The sound that will play, based on SoundRootPath.

RewardScore

The sound that plays when the player has hit the reward score.

Sound (path)

The sound that will play, based on SoundRootPath.

Grades

A "grade" is a rank the player can get. This determines the count of ranges in the minigame; each range corresponds to a grade.

Grade

Name (string)

The name of the grade; will appear when the player hits its respective range in the minigame.

NamePlural (string)

The plural name of the grade; will appear in Stats.

Value (int)

The reward value of the grade, in points.

Weight (float)

The "weight" of the grade; used to determine accuracy score in Stats.

IsFailure (bool)

If the player hits this grade's respective range, will count as failure.

DialoguePoolID (string; optional)

If the player hits this grade, the character will speak dialogue from this pool (see dialogue.xml)

Sound (path)

This sound will play when the grade is hit.

Saves

Outside of resources, Feed Snivy also has a few files it writes outside of the game. You will find these in %AppData%/snivy on Windows and ~/.local/share/snivy on Linux.

settings.xml

Stores general game settings and configuration; beyond invididual characters.

MeasurementSystem ("Imperial", "Metric")

Determines measurement system (kg/lb).

Volume (int, percent)

Master volume.

ColorR, ColorG, ColorB (float, 0-1)

Red/Green/Blue components of menu color.

WindowX, WindowY (int)

Window position.

WindowW/H (int)

Window size.

*.save

Saves are per-character; will be named "[blank].save", stored in "saves" folder, from the name of the character's archive.

Save

IsPostgame (bool)

Determines if the game has been completed (character's max stage has been reached); if true, will enable cheats.

IsAlternateSpritesheet (bool)

Determines if the character's spritesheet is using the alternate version (in Pokemon, would be the "shiny" version

Character

Weight (float)

Character's current weight, in kilograms.

Calories (float)

Character's current consumed calories.

Capacity (float)

Character's capacity, in calories. Remember, max capacity effectively is capacity * CapacityMaxMultiplier (from character.xml)

DigestionRate (float, percent)

Character's digestion rate in percent, per game tick (game ticks 60 times per second).

EatSpeed (float)

Eat speed multiplier for the character's Eat animation.

IsDigesting (bool)

Determines if character is currently digesting (when the bar is going down)

DigestionProgress (float, percent)

Character's digestion progress. Digestion max is always 100%.

DigestionTimer (int)

When digestion bar is going down, this is the remaining time to 0 (in ticks)

TotalCaloriesConsumed (float)

Total calories consumed by the character, per save file.

TotalFoodItemsEaten (int)

How many food items have been completely consumed by the character, per save file.

Play

TotalPlays (int)

However many times the "play" game has been attempted (hitting the bar counts as one "play")

HighScore (int)

Highest score the player has achieved in the "play" game.

BestCombo (int)

Highest combo the player has achieved (how many successful hits the player has gotten in one session)

Grades

Play grades are the ratings the game gives based on where the player hit.

ID (int)

ID of grade being tracked (see play.xml)

Count (int)

How many times the grade has been hit.

Inventory

Items.

ID (int)

ID of item being tracked (see items.xml)

Quantity (int)

Count of the item.

Conclusion

Hopefully this'll give you the resources you need to start making your own characters. If you need any help with this guide, or with clarification on anything, I'm available. Additionally, the game is licensed as free software, meaning if you're stuck the code should give you a clue (though I apologize for the lack of comments. Self-documenting code though, am I right? :^) )