Difference between revisions of "B2.Body"

From GiderosMobile
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A rigid body. These are created via `b2.World:createBody`.<br />
 
A rigid body. These are created via `b2.World:createBody`.<br />
 
<br />
 
<br />
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=== Examples ===
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'''Creating Box2d body and moving Bitmap along the body'''<br/>
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<source lang="lua">require "box2d"
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local world = b2.World.new(0, 10, true)
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--create ball bitmap object from ball graphic
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local ball = Bitmap.new(Texture.new("ball.png"))
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--reference center of the ball for positioning
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ball:setAnchorPoint(0.5,0.5)
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ball:setPosition(100,100)
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--get radius
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local radius = ball:getWidth()/2
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--create box2d physical object
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local body = world:createBody{type = b2.DYNAMIC_BODY}
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local circle = b2.CircleShape.new(0, 0, radius)
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local fixture = body:createFixture{shape = circle, density = 1.0,
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friction = 0.1, restitution = 0.2}
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ball.body = body
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--add to scene
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stage:addChild(ball)
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stage:addEventListener(Event.ENTER_FRAME, function()
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-- edit the step values if required. These are good defaults!
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    world:step(1/60, 8, 3)
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ball:setPosition(ball.body:getPosition())
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ball:setRotation(math.rad(ball.body:getAngle()))
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end)</source>
 
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Revision as of 11:45, 23 August 2018

Supported platforms: android, ios, mac, pc
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