--[[ Functions and constants for creating and using circles ]]--

-- It may make more sense to define these global constants in main.lua,
-- but this shows that you can define constants in files as well.
CIRCLE_DEFAULT_SPEED = 100  -- global constant
CIRCLE_DEFAULT_SIZE = 30    -- global constant

----------------------------------------
-- Functions to create circle objects --
----------------------------------------
--[[ Return a data object that has a circle's properties. ]]--
function createCircle(x_, y_, radius_, hSpeed_)
    local theCircle = {
        x = x_,
        y = y_,
        radius = radius_,
        hSpeed = hSpeed_
    }
    return theCircle
end

--------------------------------------------------
-- Functions for using/modifying circle objects --
--------------------------------------------------
--[[ Move a circle to the right, wrapping it around when necessary. ]]--
function circleMoveHorizWrap(circle, dt)
    circle.x = circle.x + circle.hSpeed * dt
    if circle.x > (love.graphics.getWidth() + circle.radius) then
        circle.x = -circle.radius
    end
end

--[[ Render a circle on the screen. ]]--
function circleRender(circle)
    love.graphics.circle("fill", circle.x, circle.y, circle.radius)
end