Difference between revisions of "B2.createMouseJointDef"

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(Created page with "__NOTOC__ '''Available since:''' Gideros 2011.6<br/> === Description === <br /> Creates and returns a mouse joint definition table with the bodies, world target point, maxForc...")
 
m (Text replacement - "</source>" to "</syntaxhighlight>")
 
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__NOTOC__
 
__NOTOC__
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<languages />
 
'''Available since:''' Gideros 2011.6<br/>
 
'''Available since:''' Gideros 2011.6<br/>
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'''Class:''' [[Special:MyLanguage/b2|b2]]<br/>
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=== Description ===
 
=== Description ===
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<br />
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Creates and returns a mouse joint definition table with the bodies, world target point, maxForce and optional frequencyHz and dampingRatio.
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Creates and returns a mouse joint definition table with the bodies, world target point, maxForce and optional frequencyHz and dampingRatio.<br />
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−
(Please refer to [[b2.World:createJoint]] function for more information about all the information needed to create a mouse joint).<br />
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(Please refer to [[b2.World:createJoint]] function for more information about all the information needed to create a mouse joint).
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<br />
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<syntaxhighlight lang="lua">
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<source lang="lua">
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(table) = b2.createMouseJointDef(bodyA,bodyB,targetx,targety,maxForce,frequencyHz,dampingRatio)
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(table), = b2.createMouseJointDef(bodyAbodyBtargetxtargetymaxForcefrequencyHzdampingRatio,)
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</syntaxhighlight>
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</source>
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'''bodyA:''' (b2.Body) the first attached body ''''''<br/>
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=== Parameters ===
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'''bodyB:''' (b2.Body) the second attached body ''''''<br/>
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'''bodyA''': (b2.Body) the first attached body <br/>
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'''targetx:''' (number) the x coordinate of the world target point ''''''<br/>
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'''bodyB''': (b2.Body) the second attached body <br/>
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'''targety:''' (number) the y coordinate of the world target point ''''''<br/>
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'''targetx''': (number) the x coordinate of the world target point <br/>
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'''maxForce:''' (number) the maximum constraint force that can be exerted to move the candidate body ''''''<br/>
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'''targety''': (number) the y coordinate of the world target point <br/>
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'''frequencyHz:''' (number, default = 5) the response speed ''''''<br/>
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'''maxForce''': (number) the maximum constraint force that can be exerted to move the candidate body <br/>
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'''dampingRatio:''' (number, default = 0.7) the damping ratio. 0 = no damping, 1 = critical damping ''''''<br/>
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'''frequencyHz''': (number, default = 5) the response speed <br/>
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'''dampingRatio''': (number, default = 0.7) the damping ratio. 0 = no damping, 1 = critical damping <br/>
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 +
=== Return values ===
 
'''Returns''' (table) A new mouse joint definition table<br/>
 
'''Returns''' (table) A new mouse joint definition table<br/>
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 +
=== Examples ===
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<syntaxhighlight lang="lua">
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--create empty box2d body for joint
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local ground = world:createBody({})
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--joint with dummy body
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local mouseJoint = nil
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-- create a mouse joint on mouse down
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function self:onMouseDown(event)
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local jointDef = b2.createMouseJointDef(ground, body, event.x, event.y, 100000)
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mouseJoint = world:createJoint(jointDef)
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end
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-- update the target of mouse joint on mouse move
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function self:onMouseMove(event)
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if mouseJoint ~= nil then
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mouseJoint:setTarget(event.x, event.y)
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end
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end
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-- destroy the mouse joint on mouse up
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function self:onMouseUp(event)
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if mouseJoint ~= nil then
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world:destroyJoint(mouseJoint)
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mouseJoint = nil
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end
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end
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</syntaxhighlight>
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 +
{{B2}}

Latest revision as of 14:27, 13 July 2023


Available since: Gideros 2011.6
Class: b2

Description

Creates and returns a mouse joint definition table with the bodies, world target point, maxForce and optional frequencyHz and dampingRatio.

(Please refer to b2.World:createJoint function for more information about all the information needed to create a mouse joint). 

(table) = b2.createMouseJointDef(bodyA,bodyB,targetx,targety,maxForce,frequencyHz,dampingRatio)

Parameters

bodyA: (b2.Body) the first attached body
bodyB: (b2.Body) the second attached body
targetx: (number) the x coordinate of the world target point
targety: (number) the y coordinate of the world target point
maxForce: (number) the maximum constraint force that can be exerted to move the candidate body
frequencyHz: (number, default = 5) the response speed
dampingRatio: (number, default = 0.7) the damping ratio. 0 = no damping, 1 = critical damping

Return values

Returns (table) A new mouse joint definition table

Examples

--create empty box2d body for joint
local ground = world:createBody({})

--joint with dummy body
local mouseJoint = nil

-- create a mouse joint on mouse down
function self:onMouseDown(event)
	local jointDef = b2.createMouseJointDef(ground, body, event.x, event.y, 100000)
	mouseJoint = world:createJoint(jointDef)
end

-- update the target of mouse joint on mouse move
function self:onMouseMove(event)
	if mouseJoint ~= nil then
		mouseJoint:setTarget(event.x, event.y)
	end
end

-- destroy the mouse joint on mouse up
function self:onMouseUp(event)
	if mouseJoint ~= nil then
		world:destroyJoint(mouseJoint)
		mouseJoint = nil
	end
end



LiquidFun

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