Fireworks with meshes

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-- Fireworks with meshes for Codea
-- v 1.0
-- Pepe, March 2015
--Touch the upper part of the screen to launch bombs
--Touch the lower part of the screen to launch rockets
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--Main

gravity = .02
size = 10

fires = {}
particles = {}

function draw()
    fill(0, 0, 0, 26)          --Transparent black (25%  opacity)
    rect(0, 0,WIDTH, HEIGHT)   --Erases background, automaticaly drawing tails  
    Fire.mesh:clear()
    for i,fire in ipairs(fires) do
        if (fire:draw()==false) then table.remove(fires,i) end
    end
    Fire.mesh:draw()
    
    Particle.mesh:clear()
    for i,particle in ipairs(particles) do
        if (particle:draw()==false) then table.remove(particles,i) end
    end
    Particle.mesh:draw()
end

function touched(touch)
    if touch.y>HEIGHT/2 then fireType = 0 else fireType = 1 end  --Upper half: bomb; Lower: rocket
    table.insert(fires, Fire(touch.x, 0, fireType, color(255,50,10), math.random(), math.random()*2, 180, math.random(1,4)))
end

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Fire = class()

Fire.mesh = mesh()
Fire.mesh.texture=readImage("Planet Cute:Star")
function Fire:init(x,y,type,tailColor,pHue,speed,life,randomness)
        self.pos = vec2(x, y)
        self.life = life
        self.col = tailColor
        self.type = type
        self.pHue=pHue
        self.speed=speed
        self.randomness = randomness
        self.active = true
        if self.type==0 then self.vel = vec2(0, 4 + math.random()*1.2)  --BOMB
                        else self.vel = vec2(0, 2 + math.random()*1.2)  --ROCKET
        end
end

function Fire:draw()
        if (self.pos.x > HEIGHT + 200 or 
            self.pos.x < 0 or
            self.pos.y > WIDTH + 200 or
            self.pos.y < -200) then self.active = false    --if out of the screen
        end
        self.life = self.life - 1  --BOMB
        if self.type == 0 then
            if (self.life < 0) then
                for i = 0, 100 do
                    table.insert(particles,Particle(self.pos, self.vel, self.pHue, 400, self.speed, 6, self.randomness))
                end
                self.active = false
            end
            self.pos = self.pos + vec2(math.random(-1, 1),math.random(-1, 1))
            self.vel.y = self.vel.y - gravity
            self.pos = self.pos + self.vel
            self.rect = self.mesh:addRect(self.pos.x,self.pos.y,size,size,0)
            self.mesh:setRectColor(self.rect, self.col)
        elseif self.type == 1 then      --ROCKET
            if (self.life <0) then self.active = false end
            self.pos = self.pos + self.vel
            table.insert(particles, Particle(self.pos, self.vel, self.pHue, 150, math.random()/5, 3, 2))
        end
        return self.active
end

---------------------------------

Particle = class()

Particle.mesh = mesh()
Particle.mesh.texture=readImage("Planet Cute:Star")

function Particle:init(pos,vel,pHue,life,speed,pSize,randomness)
        self.active = true
        self.pos = vec2(pos.x, pos.y)
        self.life = life * (math.random()) * (math.random()) * (math.random())
        self.col = hsv2rgb(pHue+math.random()/10,1,1)
        self.vel = vec2(0,1):rotate(math.random(360)) * speed + vel
        self.vel = self.vel * (math.random()*3+1)
        self.size = pSize;
end

function Particle:draw()
        self.vel = self.vel * .96    --friction
        self.vel.y = self.vel.y - gravity
        self.pos = self.pos + self.vel
        self.life = self.life - 1
        if (self.life <1) then self.active = false end
        self.rect = self.mesh:addRect(self.pos.x,self.pos.y,size,size,0)
        self.mesh:setRectColor(self.rect, self.col)
        return self.active;
end

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function hsv2rgb(H,S,V)
    if ( S == 0 ) then --//HSV from 0 to 1
       R = V * 255
       G = V * 255
       B = V * 255
    else
       var_h = H * 6
       if ( var_h == 6 ) then var_h = 0 end --H must be < 1
       var_i = math.floor ( var_h )
       var_1 = V * ( 1 - S )
       var_2 = V * ( 1 - S * ( var_h - var_i ) )
       var_3 = V * ( 1 - S * ( 1 - ( var_h - var_i ) ) )
    
       if ( var_i == 0 ) then var_r = V ; var_g = var_3 ; var_b = var_1
       elseif ( var_i == 1 ) then var_r = var_2 ; var_g = V ; var_b = var_1
       elseif ( var_i == 2 ) then var_r = var_1 ; var_g = V ; var_b = var_3
       elseif ( var_i == 3 ) then var_r = var_1 ; var_g = var_2 ; var_b = V
       elseif ( var_i == 4 ) then var_r = var_3 ; var_g = var_1 ; var_b = V
       else var_r = V ; var_g = var_1 ; var_b = var_2
       end
    
       R = var_r * 255 --RGB results from 0 to 255
       G = var_g * 255
       B = var_b * 255
       return color(R,G,B)
    end
end