Indev version of snow for Starfall!

snow.lua

--@name Snow!
--@author Feven Kitsune
--@client

local emitter = particle.create( chip():getPos(), false)
local size = 100
local ready = false
local pmax = 100
if hasPermission("convar") then
    pmax = convar.getInt("sf_particles_max")
end
local pdietime = 6.5
local ppt = 1 -- particles per tick, default 1
local tickrate = pdietime / pmax
local psizemin = 2
local psizemax = 5

local textures = {
    "https://i.imgur.com/4P3xSl4.png",
    "https://i.imgur.com/RCRIAgQ.png",
    "https://i.imgur.com/N9hRt4t.png",
    "https://i.imgur.com/gcBR930.png"
}

local loaded_materials = {}

local function HandleMaterial(mtl, url, width, height, layout)
    if not width or not height then
        mat:setTexture("$basetexture", "hunter/myplastic")
        print("Invalid texture URL")
        return
    end
    
    local xScale = 1024 / width
    local yScale = 1024 / height
    layout(0, 0, width * xScale, height * yScale, true)
    table.insert(loaded_materials, mtl)
    ready = true
end

for _, v in ipairs(textures) do
    local mat = material.create("UnlitGeneric")
    mat:setTextureURL("$basetexture", v, HandleMaterial)
    mat:setInt("$flags",256)
end

timer.create("SnowSpawn", tickrate, 0, function()
    if not ready then return end -- no materials have been loaded yet, return
    for i = 1, ppt do
        local psize = math.rand( psizemin, psizemax )
        if not emitter:isValid() then return end
        if emitter:getParticlesLeft() < 1 then return end
        local part = emitter:add( table.random(loaded_materials),
            chip():localToWorld(Vector(math.rand(-size, size), math.rand(-size, size), math.rand(0, 1))), -- position
            psize,  -- start size
            psize,  -- end size
            psize,  -- start length
            psize,  -- end length
            255,-- start alpha
            255,  -- end alpha
            pdietime   -- die time
        ) -- Create a new particle at pos
        if ( part ) then
            part:setGravity( Vector( 0, 0, -10 ) ) -- Gravity of the particle
            part:setVelocity( Vector(math.rand(-1, 1),math.rand(-1, 1),math.rand(-.1, 0)) * 10 ) -- Initial velocity of the particle
            part:setCollide( true )
        end
    end
end)

hook.add("removed", "removeEmitter", function()
    emitter:destroy()
end)

12/17/2023 @ 2:40pm:

• Made material loading more flexible.

12/17/2023 @ 3:33pm:

• Added variable particle size
• Added better tick control, still needs work. Ideally the particle count should scale with the client's allowed particles without causing choppiness in the spawn rate (ex. failed spawn ticks, causing gaps in the snowfall)

12/17/2023 @ 2:54pm:

• Updated time, system clock was off.
• Added permissions check for convar