CodeaBalls V1

gistfile1.txt

--# Main
supportedOrientations(LANDSCAPE_RIGHT)
displayMode(OVERLAY)
-- CodeaBalls

-- Use this function to perform your initial setup
function setup()
    edge1 = physics.body( EDGE, vec2(0,0), vec2(WIDTH,0) )
    edge1.type = STATIC
    edge1.sleepingAllowed = false

    edge2 = physics.body( EDGE, vec2(WIDTH,0), vec2(WIDTH,HEIGHT) )
    edge2.type = STATIC
    edge2.sleepingAllowed = false

    edge3 = physics.body( EDGE, vec2(WIDTH,HEIGHT), vec2(0,HEIGHT) )
    edge3.type = STATIC
    edge3.sleepingAllowed = false

    edge4 = physics.body( EDGE, vec2(0,HEIGHT), vec2(0,0) )
    edge4.type = STATIC
    edge4.sleepingAllowed = false

    BTest = Ball(WIDTH/2,HEIGHT/2,80,2,3)

    parameter.boolean("debugBall",false)
    parameter.number("DampingRato",0.5,30,3,function(v) BTest:setDamping(v) end)
    parameter.number("Frequency",0.5,30,2,function(v) BTest:setFrequency(v) end)
end

-- This function gets called once every frame
function draw()
    -- This sets a dark background color
    background(0, 184, 255, 255)

    -- This sets the line thickness
    strokeWidth(BTest.radius/3)
    stroke(0, 120, 255, 255)
    if debugBall then
        strokeWidth(5)
        fill(255, 0, 0, 0)
    else
        fill(0,100,235,255)
    end

    for i = 1,4 do
        local edg = _G["edge"..i]
        line(edg.points[1].x,edg.points[1].y,edg.points[2].x,edg.points[2].y)
    end

    -- Do your drawing here
    BTest:draw(debugBall)

    physics.gravity(Gravity)
end


--# Ball
Ball = class()

function Ball:init(x,y,radius,damping,frequency)
    -- the position we will create the softbody at
    self.x, self.y = x or 0, y or 0

    -- the radius of the entire softbody
    self.radius = radius or 124

    -- the amount of outer nodes
    local nodes = self.radius/4

    -- the frequency and damping of our physics
    self.damping = damping or 0.4
    self.frequency = frequency or 0.8

    -- lets create our center body and store it in a table
    self.centerNode = physics.body( CIRCLE, 32 )
    self.centerNode.x, self.centerNode.y = self.x, self.y
    self.centerNode.sleepingAllowed = false

    -- next lets create our outer nodes and store them in a table
    self.outerNodes = {}

    for node = 1, nodes do

        -- the angle from the center body to the outer node
        local angle = (2 * math.pi) / nodes * node

        -- get the position of the new node using the angle and radius as offset
        local nodeX = self.x + self.radius * math.cos(angle)
        local nodeY = self.y + self.radius * math.sin(angle)

        -- create our body and fix our shape to it
        local nodeBody = physics.body( CIRCLE,self.radius/6 )
        nodeBody.x, nodeBody.y = nodeX, nodeY
        nodeBody.sleepingAllowed = false
        --[[
            now lets connect the node to the center body with a distanceJoint
            you may notice we use the same position for both anchor points of the joint

            I personally find this creates a much better outcome,
            as the outer nodes stay in rotation with the center body
        --]]
        local nodeJoint = physics.joint( DISTANCE, nodeBody, self.centerNode, vec2(nodeX, nodeY), vec2(nodeX, nodeY) )
        -- next lets set the damping and frequency
        nodeJoint.frequency, nodeJoint.dampingRatio = self.frequency, self.damping

        -- and finally, lets add everything to the outerNodes table
        table.insert(self.outerNodes, {body = nodeBody, joint = nodeJoint})
    end

    -- lets iterate over the nodes
    for i = 1, #self.outerNodes do
        -- we get two nodes, the one on this iteration and the following node
        local nodeA = self.outerNodes[i]

        -- get the node following i
        local nodeB = self.outerNodes[(i % #self.outerNodes) + 1]

        -- create a distanceJoint between the two nodes, this time with no frequency or damping
        nodeA.joint2 = physics.joint( DISTANCE, nodeA.body, nodeB.body, nodeA.body.position, nodeB.body.position )
    end
end

function Ball:setFrequency(frec)
    for k,node in ipairs(self.outerNodes) do
        node.joint.frequency = frec
    end
end

function Ball:setDamping(damp)
    for k,node in ipairs(self.outerNodes) do
        node.joint.dampingRatio = damp
    end
end

function Ball:draw(dbg)
    if dbg then
        ellipseMode(RADIUS)
        ellipse( self.centerNode.x, self.centerNode.y, self.centerNode.radius)

        for k,node in ipairs(self.outerNodes) do
            ellipse( node.body.x, node.body.y, node.body.radius )
            if not self.outerNodes[k+1] then tnode = self.outerNodes[1] else tnode = self.outerNodes[k+1] end
            line( node.body.x, node.body.y, tnode.body.x, tnode.body.y )
        end
    else
        for i=1,#self.outerNodes do
            local node, tnode = self.outerNodes[i]

            if not self.outerNodes[i+1] then tnode = self.outerNodes[1] else tnode = self.outerNodes[i+1] end

            if not node.mesh then node.mesh = mesh() end
            node.mesh.vertices = {
                node.body.position,
                self.centerNode.position,
                tnode.body.position
            }

            node.mesh:setColors(fill())
            node.mesh:draw()

            line( node.body.x, node.body.y, tnode.body.x, tnode.body.y )
        end
    end
end