Voxel Worm

A flying worm that draws a voxel trail behind it. The worm is controlled by a simple physics script that makes it move in a random direction and bounce off the ground.

local self = {}

function self:Start()
    --self.transform.pos = Vec3(0, 50, 8)
    self.startTime = Scene:GetTime()

    self.physics = self.object:FindScript("Simple Physics")
    assert(self.physics, "Needs Simple Physics script")
    self.physics.gravity = 10
end

function self:Update(deltaTime)
    self:checkCollision()
    self:updateEdit()
    self:updateMove()

    if self.startTime + 10 < Scene:GetTime() then
        Scene:DestroyObject(self.object)
    end
end

function self:updateMove()
    local t = Scene:GetTime() * 0.1
    local x = math.perlinNoise(t)
    local z = math.perlinNoise(0, t)
    local y = self.physics.vel.y

    self.physics.vel = Vec3.up * y + Vec3(x, 0, z) * 30

    if self.transform.pos.y < -20 then
        local pos = self.transform.pos
        pos.y = 30
        self.transform.pos = pos
    end 
end

function self:checkCollision()
    local vel = Vec3(self.physics.vel)
    vel:Normalize()
    local c = Collision()
    c.filter.useNotStatic = false
    local hit = c:Raycast(self.transform.pos, vel)[1]
    if hit then
        self.physics.vel = self.physics.vel + Vec3.up * 10
    end
end

function self:updateEdit()
    local vel = Vec3(self.physics.vel)
    vel:Normalize()
    
    --if position has changed since last frame make line
    if self.lastPos ~= self.transform.pos then
        if self.lastPos then
            --deb:line(self.lastPos, self.transform.pos + vel * 1.5)
            --self:eraseLine(self.lastPos, self.transform.pos + vel * 1.5)
            self:makeLine(self.lastPos, self.transform.pos)
        end
        self.lastPos = self.transform.pos
    end
end

--make a capsule from p1, to p2
function self:makeLine(p1, p2)
    --multiply thickness by transform scale
    local thickness = 0.1 * self.transform.scale
    local s = Capsule(p1, p2, thickness)
    local col = self:randomColor()
    local ve = VoxelEdit(s, col)
    ve.filter.useNotStatic = false
    ve:Add()
end

--make a capsule from p1, to p2
function self:eraseLine(p1, p2)
    --multiply thickness by transform scale
    local thickness = self.transform.scale * 0.5
    local s = Capsule(p1, p2, thickness)
    local ve = VoxelEdit(s)
    ve.filter.useNotStatic = false
    ve:Erase()
end

function self:randomColor()
    local t = Scene:GetTime() * 0.1
    local x = (math.perlinNoise(0, t) + 1)/2
    local y = (math.perlinNoise(1, t) + 1)/2
    local z = (math.perlinNoise(2, t) + 1)/2
    return Vec3(x,y,z)
end

return self