lovexp/main.lua

local love = require("love")

function love.load()
    arenaWidth = 800
    arenaHeight = 600
    shipX = arenaWidth / 2
    shipY = arenaHeight / 2
    shipAngle = 0
    shipSpeedX = 0
    shipSpeedY = 0
    shipRadius = 30

    bullets = {}
    bulletTimerLimit = 0.5
    bulletTimer = bulletTimerLimit
end

function love.update(dt)
    local turnSpeed = 10
    if love.keyboard.isDown('right') then
        shipAngle = shipAngle + turnSpeed * dt
    end
    if love.keyboard.isDown('left') then
        shipAngle = shipAngle - turnSpeed * dt
    end
    shipAngle = shipAngle % (2 * math.pi)

    if love.keyboard.isDown('up') then
        local shipSpeed = 100
        shipSpeedX = shipSpeedX + math.cos(shipAngle) * shipSpeed * dt
        shipSpeedY = shipSpeedY + math.sin(shipAngle) * shipSpeed * dt
    end

    shipX = (shipX + shipSpeedX * dt) % arenaWidth
    shipY = (shipY + shipSpeedY * dt) % arenaHeight

    for bulletIndex = #bullets, 1, -1 do
        local bullet = bullets[bulletIndex]
        bullet.timeLeft = bullet.timeLeft - dt
        if bullet.timeLeft <= 0 then
            table.remove(bullets, bulletIndex)
        else
            local bulletSpeed = 500
            bullet.x = (bullet.x + math.cos(bullet.angle) * bulletSpeed * dt) % arenaWidth
            bullet.y = (bullet.y + math.sin(bullet.angle) * bulletSpeed * dt) % arenaHeight
        end
    end

    bulletTimer = bulletTimer + dt
    if love.keyboard.isDown('s') then
        if bulletTimer >= bulletTimerLimit then
            bulletTimer = 0
            table.insert(bullets, {
                x = shipX + math.cos(shipAngle) * shipRadius,
                y = shipY + math.sin(shipAngle) * shipRadius,
                angle = shipAngle,
                timeLeft = 4,
            })
        end
    end
end

function love.draw()
    for y = -1, 1 do
        for x = -1, 1 do
            love.graphics.origin()
            love.graphics.translate(x * arenaWidth, y * arenaHeight)
            love.graphics.setColor(0, 0, 1)
            love.graphics.circle('fill', shipX, shipY, shipRadius)
            local shipCircleDistance = 20
            love.graphics.setColor(0, 1, 1)
            love.graphics.circle(
                'fill',
                shipX + math.cos(shipAngle) * shipCircleDistance,
                shipY + math.sin(shipAngle) * shipCircleDistance,
                5
            )

            for bulletIndex, bullet in ipairs(bullets) do
                love.graphics.setColor(0, 1, 0)
                love.graphics.circle('fill', bullet.x, bullet.y, 5)
            end
        end
    end

    love.graphics.origin()
    love.graphics.setColor(1, 1, 1)
    love.graphics.print(table.concat({
        'shipAngle:' .. shipAngle,
        'shipX: ' .. shipX,
        'shipSpeedX: ' .. shipSpeedX,
    }, '\n'))
end