B2.Body

Supported platforms:
Available since: Gideros 2011.6

Description

A rigid body. These are created via b2.World:createBody.

Examples

Creating Box2d body and moving Bitmap along the body

require "box2d"
local world = b2.World.new(0, 10, true)

--create ball bitmap object from ball graphic
local ball = Bitmap.new(Texture.new("ball.png"))
--reference center of the ball for positioning
ball:setAnchorPoint(0.5,0.5)
 
ball:setPosition(100,100)
 
--get radius
local radius = ball:getWidth()/2
 
--create box2d physical object
local body = world:createBody{type = b2.DYNAMIC_BODY}
local circle = b2.CircleShape.new(0, 0, radius)
local fixture = body:createFixture{shape = circle, density = 1.0, 
friction = 0.1, restitution = 0.2}
ball.body = body
 
--add to scene
stage:addChild(ball)

stage:addEventListener(Event.ENTER_FRAME, function()
	-- edit the step values if required. These are good defaults!
    world:step(1/60, 8, 3)
	ball:setPosition(ball.body:getPosition())
	ball:setRotation(math.rad(ball.body:getAngle()))
end)

Methods b2.Body:applyAngularImpulse applies an angular impulse b2.Body:applyForce applies a force at a world point b2.Body:applyLinearImpulse applies an impulse at a point b2.Body:applyTorque applies a torque b2.Body:createFixture creates a fixture and attach it to this body b2.Body:destroyFixture destroys a fixture b2.Body:getAngle returns the current world rotation angle in radians b2.Body:getAngularDamping returns the angular damping of the body b2.Body:getAngularVelocity returns the angular velocity b2.Body:getGravityScale returns the gravity scale of the body b2.Body:getInertia returns the rotational inertia of the body about the local origin in kg-m^2 b2.Body:getLinearDamping returns the linear damping of the body b2.Body:getLinearVelocity returns the linear velocity of the center of mass b2.Body:getLocalCenter returns the local position of the center of mass b2.Body:getLocalPoint b2.Body:getLocalVector b2.Body:getMass returns the total mass of the body in kilograms (kg) b2.Body:getPosition returns the world body origin position b2.Body:getWorldCenter returns the world position of the center of mass b2.Body:getWorldPoint b2.Body:getWorldVector b2.Body:isActive returns the active state of the body b2.Body:isAwake returns the sleeping state of the body b2.Body:isBullet b2.Body:isFixedRotation b2.Body:isSleepingAllowed b2.Body:setActive sets the active state of the body b2.Body:setAngle b2.Body:setAngularDamping sets the angular damping of the body b2.Body:setAngularVelocity sets the angular velocity b2.Body:setAwake sets the sleep state of the body b2.Body:setBullet b2.Body:setFixedRotation b2.Body:setGravityScale sets the gravity scale of the body b2.Body:setLinearDamping sets the linear damping of the body b2.Body:setLinearVelocity sets the linear velocity of the center of mass b2.Body:setPosition sets the world body origin position b2.Body:setSleepingAllowed

Events Constants