B2.createGearJointDef
From GiderosMobile
Available since: Gideros 2011.6
Class: b2
Description
Creates and returns a gear joint definition table.
(Please refer to b2.World:createJoint function for more information about all the information needed to create a gear joint).
(table) = b2.createGearJointDef(bodyA,bodyB,joint1,joint2,ratio)
Parameters
bodyA: (b2.Body) the first attached body
bodyB: (b2.Body) the second attached body
joint1: (b2.Joint) the first revolute/prismatic joint attached to the gear joint
joint2: (b2.Joint) the second revolute/prismatic joint attached to the gear joint
ratio: (number, default = 1) the gear ratio
Return values
Returns (table) A new gear joint definition table
Examples
Gear joint combining revolute and prismatic joints
--create empty box2d body for joint
local ground = world:createBody({})
--create revolute joint
--note that ground should be passed as first parameter here
local jointDef = b2.createRevoluteJointDef(ground, body1, 300, 300)
local revoluteJoint = world:createJoint(jointDef)
--set motor
revoluteJoint:setMaxMotorTorque(1)
revoluteJoint:enableMotor(true)
--axisx, axisy values usually between 0 and 1
--note that ground should be passed as first parameter here
local jointDef = b2.createPrismaticJointDef(ground, body2, 350, 100, 0.3, 1)
local prismaticJoint = world:createJoint(jointDef)
--set motor
prismaticJoint:setMaxMotorForce(1)
prismaticJoint:enableMotor(true)
--create gear joint using two already created joints
local jointDef = b2.createGearJointDef(body1, body2, revoluteJoint, prismaticJoint, 1)
local gearJoint = world:createJoint(jointDef)