FSM or Finite State Machine allows you to extend sprites animation and entities behavior on general. It is a set of lines that describe what sprites enemy or decorations will have and what will they do. In short, you can change how many sprites an entity has and how fast frames will switch one another.
To add a state machine, you need to create a file with the .states extension and the name of the weapon, enemy, or decoration in the ProjectName/States folder. When adding a state machine, the attack and reload speed will no longer depend on the setting in the editor - everything will be controlled only by the duration of the frames specified in the file. In addition, all sprites and (for weapons) some of the sounds will need to be loaded manually using the image and sound commands.
Never have a space or tab Infront of any string. (White space is also counted when the engine reads the FSM/Script or script and unexpected spaces will break the FSM/Script)
frameset 4 28 0 0 0 NONE (This plays frames 4 through to 28 so that you don't have to write out each line)
frame 29 0 0 0 ATTACK (sets the attack)
frame 30 0 0 0 READY
Basic FSM for enemies:
image Enemy 0 12
state IDLE NONE 0
frame 0 0.125 0 0 0 NONE
frame 0 0.125 0 0 0 READY
state SEE CHASE 0
frame 0 0.125 0 0 0 NONE
frame 0 0.125 0 0 0 READY
state CHASE NONE 0
frame 1 1 0 0 0 NONE
frame 2 1 0 0 0 NONE
frame 3 1 0 0 0 NONE
frame 4 1 0 0 0 READY
state ATTACK CHASE 0
frame 5 0.25 0 0 0 NONE
frame 5 0.25 0 0 0 NONE
frame 6 0.0625 0 0 0 NONE
frame 6 0.0625 0 0 0 ATTACK
frame 5 0.25 0 0 0 NONE
frame 5 0.25 0 0 0 READY
state HURT CHASE 0
frame 7 0.125 0 0 0 NONE
frame 8 0.125 0 0 0 NONE
state DEATH DEAD 0
frame 9 0.166 0 0 0 NONE
frame 10 0.166 0 0 0 NONE
frame 11 0.166 0 0 0 NONE
state DEAD NONE 0
frame 12 0.125 0 0 0 NONE
frame 12 0.125 0 0 0 NONE
Intermediate FSM for enemies:
image BORIS 0 455
sound AK
state IDLE NONE 0
frameset 2 254 0.025 0 0 0 NONE
frame 255 0.025 0 0 0 NONE
frame 256 0.025 0 0 0 READY
state SEE CHASE 0
frameset 262 281 0.025 0 0 0 NONE
frame 282 0.025 0 0 0 NONE
frame 283 0.025 0 0 0 READY
state CHASE SEE 0
frameset 262 281 0.025 0 0 0 NONE
frame 282 0.025 0 0 0 NONE
frame 283 0.025 0 0 0 READY
state ATTACK CHASE 0
frame 463 0.025 0 0 0 NONE
frame 464 0.025 0 0 0 SOUNDANDATTACK 0
frameset 465 496 0.025 0 0 0 NONE
frame 497 0.025 0 0 0 READY
state HURT FLEE 0
frameset 286 340 0.025 0 0 0 NONE
frame 341 0.025 0 0 0 NONE
frame 342 0.025 0 0 0 READY
state FLEE SEE 0
frameset 262 281 0.025 0 0 0 NONE
frame 282 0.025 0 0 0 NONE
frame 283 0.025 0 0 0 READY
state SEE FLEE 0
frameset 262 281 0.025 0 0 0 NONE
frame 282 0.025 0 0 0 NONE
frame 283 0.025 0 0 0 READY
state FLEE CHASE 0
frameset 262 281 0.025 0 0 0 NONE
frame 282 0.025 0 0 0 NONE
frame 283 0.025 0 0 0 READY
state DEATH DEAD 0
frameset 357 453 0.025 0 0 0 NONE
frame 454 0.025 0 0 0 NONE
frame 455 0.025 0 0 0 NONE
state DEAD NONE 0
frame 455 0.025 0 0 0 NONE
Basic FSM for decorations:
image Decoration 0 3
state IDLE NONE 0
frame 0 0.25 0 0 0 NONE
frame 0 0.25 0 0 0 READY
state DEATH DEAD 0
frame 1 0.166 0 0 0 NONE
frame 2 0.166 0 0 0 NONE
frame 3 0.166 0 0 0 NONE
state DEAD NONE 0
frame 3 0.25 0 0 0 NONE
frame 3 0.25 0 0 0 NONE
Let's take a look:
image Decoration 0 3 - loads sprites and adds them to a list. They are numbered from 0. In this case this command will load every sprite from "Decoration0" to "Decoration3". Sprites must be placed in Data/Sprites/ with apropriate entity folder (Decorations or Enemies) or weapons(Weapons). e.g. "Data/Sprites/Decorations". Weapon sprites MUST have frame 0 which is used for sprites on the floor.
image Decoration - will load only one sprite (in this case named "Decoration") and add it to a list.
sound WeaponFire - will load a sound and add it to a list. They are numbered from 0. Sounds must be placed in Data/Sounds.
state IDLE NONE 0 - creates a new state, where IDLE is a name, NONE - name of the next state to jump to after this one is done (if it's NONE, current state will be looped), 0 (или 1) - sets if you want this state to interpolate model frames or not (if you use 3D models).
frame 0 0.25 0 0 0 NONE - adds a frame to the latest created state. Here 0 - number of a sprite that was loaded (see earlier), 0.25 - time this frame will be staying on screen, 0 0 0 - offset coordinates (only for weapons), NONE - action (see further down).
States shown in examples are MANDATORY to create. There might be many other states, however enemies will only move while in CHASE state. Enemy will spawn blood when in state HURT.
There's also an additional state for weapons called ALTATTACK and can be used to use your weapon with right mouse button.
Actions:
NONE - empty. Does nothing.
ATTACK - weapon or enemy attack
READY - sets if entity is ready to attack. Mandatory after enemy or weapon attack.
FLEE - sets a flee state for the enemy that makes them run away
HURT - sets a hurt state for the enemy. This can work with the FLEE state for example, HURT FLEE will set the enemy to flee after taking damage for a short time.
SOUND 0 - plays a sound, 0 - number of a loaded sound (see earlier).
SOUNDANDATTACK 0 - does attack and plays sound in one action.
SETVAR name value - sets variable to a certain value. You can use RANDOM(0,100) instead of value. The value will be randomized from 0 to 100. You can also use global. and map. prefixes to set global or map variables (see Scripting). Actually - the generated random number will always be lower than the top value by one. This means that RANDOM(0,100) will generate any number in numeric segment from 0 to 99. It will never generate value equal to 100.If you would, for example, simulate a coin flip with each side having 50% chance, with zero means heads and one means tails - you must use RANDOM(0,2) action, because it will generate only zero's or one's. RANDOM(0,1) will always output only zero's. This is true for the latest - Dec 28, 2022 - 12th version of EFPSE currently available on Itch.io.
INCREMENT name value - increments the value of a variable, i.e. increases by 1.
DECREMENT name value - decrements the value of a variable, i.e. decreases by 1.
JUMPIFEQUALS variable value state - moves to another state if variable value equal to the one we want. You can also use global. and map. prefixes.
JUMPIFNEQUALS variable value state - moves to another state if variable value is not equal to the one we want. You can also use global. and map. prefixes.
JUMPIFGEQUALS variable value state - moves to another state if variable value equal or greater to the one we want. You can also use global. and map. prefixes.
JUMPIFLEQUALS variable value state - moves to another state if variable value equal or less to the one we want. You can also use global. and map. prefixes.
JUMPIFGREATER variable value state - moves to another state if variable value greater to the one we want. You can also use global. and map. prefixes.
JUMPIFLESS variable value state - moves to another state if variable value less to the one we want. You can also use global. and map. prefixes.
JUMPIFLESSAMMO state - moves to another value if ammo in magazine is lower than maximum (weapons only).
JUMPIFNOAMMO state - moves to another state if magazine is empty (weapons only).
GIVEAMMO - gives 1 ammo to a magazine. (weapons only).
TAKEAMMO - takes one ammo from magazine (weapons only).
RELOAD - reloads magazine (weapons only).
MUZZLEFLASH - shows muzzle flash (weapons only).
PARTICLES imageindex i,l,x,y,z dx,dy,dz - creates particles. imageindex - number of sprite loaded, i - number of particles, l - particle lifetime, x,y,z - coordinates. Coordinates are local to enemy or player, meaning that 0,0,1 will always be in front of enemy or player. x - side offset, y - vertical offset, z - forward offset. dx,dy,dz - particle velocity. Also local to entity.
EXPLOSION name radius - creates an explosion with a name and radius where name is name of explosion sprites. Sprites must be place in Data/Sprites/Effects (enemies only).
SPAWN name x,y,z f,v - creates an entity with a name (enemies and decoration) or a keyword (Key1, Key2, Key3, Hp1, Hp2, Hp3, Hp4, Ammo1, Ammo2, Ammo3... etc.). x,y,z - just like with particles, f - front velocity when spawned, v - vertical velocity when spawning. (enemies and decorations only).
PLAYERSPEED - controls player's movement. You can only entirely freeze the movement (if set to 0) and enable it back (if set to 1), or double it (if set to 2).
All key words are CASE SENSITIVE Also be wary of whitespaces, they are important for engine to correctly parse parameters. Only latin characters are allowed.
An Example of a working FSM for a weapon with a Alt fire which fires 3 shots in quick succession.
