verlet-physics

A simple verlet physics for LÖVE I made this library using a video from the Pezzza's Work channel, if you want to help with errors and generally improve the code, then please fork this repository. There may be a lot of illogical points in the code as I was working on this library late at night and wanted to sleep...zzZ

Example

local verlet = require("verlet")
local vector = require("vector")
require("color")

local asc = 0
local delta = 0
curtime = 0

local scrw,scrh = love.window.getDesktopDimensions(1)
love.window.setMode( scrw/1.2, scrh/1.2, {
    vsync = 1,
    msaa = 1,
    resizable = 1
})

local function makeExplode(x,y)
    local pos = vector(x,y)
    for i=1, #objects do
        local vel = (objects[i].pos - pos):normalizeInplace()
        local dist = pos.dist(objects[i].pos, pos)

        objects[i]:addVelocity(vel * -dist, delta)
    end
end

local function crtObj(x,y)
    asc = asc + 1
    objects[asc] = verlet.new()
    objects[asc]:setPos(vector(x,y))
    objects[asc].radius = math.floor(math.random(5,15))
    local r,g,b = hsvToRgb(curtime/1000,0.8,1,1)
    objects[asc].color = {r/255,g/255,b/255}
    local pos,radius = verlet.getConstraint()
    --local x1,y1 = love.mouse.getPosition()
    local vel = ((pos + vector(math.sin(curtime/50)*radius,math.cos(curtime/50)*radius)) - pos):normalizeInplace()
    --local vel = (vector(x1,y1) - vector(x,y)):normalizeInplace()
    objects[asc]:setVelocity(vel * 1000, delta)
end

function love.load()
    objects = {}
end

function love.update(dt)
    delta = dt

    if #objects < 600 then
        local w,h = love.graphics.getDimensions()
        crtObj(w/2,(h/2)-150)
    end

    curtime = curtime + 1
    verlet.update(dt,objects)
end

function love.draw()
    verlet.draw(objects)

    love.graphics.print("FPS: " .. love.timer.getFPS() .. " Objects: " .. #objects,5,5)
end

Functions

(table obj) verlet.new()

Creates and returns a new object.

obj:setPos(vec2 pos)

Moves an object to some position.

obj:setVelocity(vel, dt)

Sets the velocity of the object.

obj:addVelocity(vel, dt)

Adds a new speed of the object to the current one.

obj:updatePosition(dt)

Updates the position, used by the function verlet.update(int dt,table objects).

obj:accelerate(acc)

Adds a new acceleration to the current one.

(vec2 pos, int radius) verlet.getConstraint()

Returns the position and radius of the circle in which objects can be located.

verlet.applyConstraint(table object)

Prevents objects from going outside the circle.

verlet.solveCollisions(table objects)

Resolves collisions between objects

verlet.update(int dt,table objects)

Updates the physics of all objects.

verlet.draw(table objects)

Draws objects in the form of circles with different sizes and colors.

Known bugs

The psyche of objects (no matter how strange it may sound)

Moving a window, changing its size and constantly Alt+Tab provokes objects to go crazy.

looping all objects to check for collisions with one object?! shit.

This optimization problem can be solved very easily, the Pezzza's Work channel will improve its physics engine and just replace the nasty loop with a system with grid cells.