Class me.ObjectEntity

Extends me.AnimationSheet.

Defined in: <build/melonJS-0.9.3.js>.

Class Summary
Constructor Attributes	Constructor Name and Description
	me.ObjectEntity(x, y, settings) a Generic Object Entity Object Properties (settings) are to be defined in Tiled, or when calling the parent constructor

Field Summary
Field Attributes	Field Name and Description
	accel entity current acceleration
	alive dead/living state of the entity default value : true
	canBreakTile Define if an entity can go through breakable tiles default value : false
	falling falling state of the object true if the object is falling false if the object is standing on something (!) READ ONLY property
	friction entity current friction
	gravity Default gravity value of the entity default value : 0.98 (earth gravity) to be set to 0 for RPG, shooter, etc.
	GUID Entity "Game Unique Identifier"
	jumping jumping state of the object equal true if the entity is jumping (!) READ ONLY property
	maxVel max velocity (to limit entity velocity)
	onladder equal true if the entity is on a ladder (!) READ ONLY property
	onslope equal true if the entity is standing on a slope (!) READ ONLY property
	onTileBreak a callback when an entity break a tile
	vel entity current velocity

Fields borrowed from class me.AnimationSheet:: animationspeed
Fields borrowed from class me.SpriteObject:: autodestroy, visible
Fields borrowed from class me.Rect:: bottom, height, left, pos, right, top, width

Method Summary
Method Attributes	Method Name and Description
	distanceTo(entity) return the distance to the specified entity
	doClimb(up) helper function for platform games: make the entity move up and down only valid is the player is on a ladder
	doJump() helper function for platform games: make the entity jump
	doWalk(left) helper function for platform games: make the entity move left of right
	forceJump() helper function for platform games: force to the entity to jump (for double jump)
	onCollision(res, obj) onCollision Event function called by the game manager when the object collide with shtg by default, if the object type is Collectable, the destroy function is called
	setFriction(x, y) set the entity default friction
	setMaxVelocity(x, y) cap the entity velocity to the specified value (!) this will only cap the y velocity for now(!)
	setVelocity(x, y) set the entity default velocity note : velocity is by default limited to the same value, see setMaxVelocity if needed
	updateColRect(x, w, y, h) specify the size of the hit box for collision detection (allow to have a specific size for each object) e.g.
	updateMovement() handle the player movement, "trying" to update his position

Methods borrowed from class me.AnimationSheet:: addAnimation, isCurrentAnimation, setAnimationFrame, setCurrentAnimation, update
Methods borrowed from class me.SpriteObject:: draw, flicker, flipX, flipY, isFlickering, onDestroyEvent, resize, setTransparency
Methods borrowed from class me.Rect:: contains, containsPoint, getRect, overlaps, set, union, within

Class Detail

me.ObjectEntity(x, y, settings)

a Generic Object Entity
Object Properties (settings) are to be defined in Tiled,
or when calling the parent constructor

Parameters:
{int} x: the x coordinates of the sprite object
{int} y: the y coordinates of the sprite object
{me.ObjectSettings} settings: Object Properties as defined in Tiled

Field Detail

{me.Vector2d} accel

entity current acceleration

{Boolean} alive

dead/living state of the entity
default value : true

{Boolean} canBreakTile

Define if an entity can go through breakable tiles
default value : false

{Boolean} falling

falling state of the object
true if the object is falling
false if the object is standing on something
(!) READ ONLY property

{me.Vector2d} friction

entity current friction

{Number} gravity

Default gravity value of the entity
default value : 0.98 (earth gravity)
to be set to 0 for RPG, shooter, etc...

{String} GUID

Entity "Game Unique Identifier"

{Boolean} jumping

jumping state of the object
equal true if the entity is jumping
(!) READ ONLY property

{me.Vector2d} maxVel

max velocity (to limit entity velocity)

{Boolean} onladder

equal true if the entity is on a ladder
(!) READ ONLY property

{Boolean} onslope

equal true if the entity is standing on a slope
(!) READ ONLY property

{Function} onTileBreak

a callback when an entity break a tile

{me.Vector2d} vel

entity current velocity

Method Detail

{float} distanceTo(entity)

return the distance to the specified entity

Parameters:
{me.ObjectEntity} entity: Entity

Returns:: {float} distance

doClimb(up)

helper function for platform games:
make the entity move up and down
only valid is the player is on a ladder

if (me.input.isKeyPressed('up'))
{
    this.doClimb(true);
}
else if (me.input.isKeyPressed('down'))
{
    this.doClimb(false);
}

Parameters:
{Boolean} up: will automatically flip vertically the entity sprite

doJump()

helper function for platform games:
make the entity jump

doWalk(left)

helper function for platform games:
make the entity move left of right

if (me.input.isKeyPressed('left'))
{
    this.doWalk(true);
}
else if (me.input.isKeyPressed('right'))
{
    this.doWalk(false);
}

Parameters:
{Boolean} left: will automatically flip horizontally the entity sprite

forceJump()

helper function for platform games:
force to the entity to jump (for double jump)

onCollision(res, obj)

onCollision Event function
called by the game manager when the object collide with shtg
by default, if the object type is Collectable, the destroy function is called

Parameters:
{me.Vector2d} res: collision vector
{me.ObjectEntity} obj: the other object that hit this object

setFriction(x, y)

set the entity default friction

Parameters:
{Int} x: horizontal friction
{Int} y: vertical friction

setMaxVelocity(x, y)

cap the entity velocity to the specified value
(!) this will only cap the y velocity for now(!)

Parameters:
{Int} x: max velocity on x axis
{Int} y: max velocity on y axis

setVelocity(x, y)

set the entity default velocity
note : velocity is by default limited to the same value, see setMaxVelocity if needed

Parameters:
{Int} x: velocity on x axis
{Int} y: velocity on y axis

updateColRect(x, w, y, h)

specify the size of the hit box for collision detection
(allow to have a specific size for each object)
e.g. : object with resized collision box :

Parameters:
{int} x: x offset (specify -1 to not change the width)
{int} w: width of the hit box
{int} y: y offset (specify -1 to not change the height)
{int} h: height of the hit box

{me.Vector2d} updateMovement()

handle the player movement, "trying" to update his position

// make the player move
if (me.input.isKeyPressed('left'))
{
    this.vel.x -= this.accel.x * me.timer.tick;
}
else if (me.input.isKeyPressed('right'))
{
    this.vel.x += this.accel.x * me.timer.tick;
}
// update player position
var res = this.updateMovement();

// check for collision result with the environment
if (res.x != 0)
{
  // x axis
  if (res.x<0)
     console.log("x axis : left side !");
  else
     console.log("x axis : right side !");
}
else if(res.y != 0)
{
   // y axis
   if (res.y<0)
      console.log("y axis : top side !");
   else
      console.log("y axis : bottom side !");		
		
	  // display the tile type
   console.log(res.yprop.type)
}

// check player status after collision check
var updated = (this.vel.x!=0 || this.vel.y!=0);

Returns:: {me.Vector2d} a collision vector

melonJS

A lightweight HTML5 game engine

API Document Index

Class me.ObjectEntity