LÖVE

BlackBulletIV wrote:Don't forget the width and height! It's also best to use the getWidth/Height functions (or some variables), to make your code more abstract, as in, less reliant on outside conditions.

Taehl wrote:A very simple way

miko wrote: You don't want do access global variables and make a call to get*() on every iteration. So the modified example would be:

Code: Select all

function love.draw()
  local width, height=love.graphics.getWidth(), love.graphics.getHeight()
  local draw=love.graphics.draw
  for i, enemy in ipairs(enemies) do
    if enemy.x > -enemy.width and enemy.x < width
       and enemy.y > -enemy.height and enemy.y < height   
    then
      draw(img_enemy, enemy.x, enemy.y)
    end
  end
end

BlackBulletIV wrote:I've personally taken the route of caching those values in love.graphics.width and love.graphics.height, and then of course adjusting them whenever something changes. This would be much faster and convenient, and it's certainly practical, because the width and height will hardly ever, or not at all, change.

Lafolie wrote:

BlackBulletIV wrote:I've personally taken the route of caching those values in love.graphics.width and love.graphics.height, and then of course adjusting them whenever something changes. This would be much faster and convenient, and it's certainly practical, because the width and height will hardly ever, or not at all, change.

You mean you just store them in a global var? It's probably faster than storing them in a local value in each function that uses them in an iteration, even if it is calling a global. Perhaps you could still uses the locals, but pull the value from the globals instead of issuing love.graphics.get*() and it would be faster still? Hmmmm.

No, not a global variable. A variable nested inside the table love.graphics. The only global there is love itself. I'm not quite sure what you're meaning by that last sentence, but if you made love.graphics.get*() just return a value stored in Lua, I certainly think it would be faster (no going up to the C level).

width = love.graphics.getWidth()
height = love.graphics.getHeight()

function iterator()
	local w = width
	local h = height
	for i = 1, 10 do
		love.graphics.setColor(255, 255, 255, 10 * i)
		love.graphics.rectangle("fill", 10 * i, 10 * i, w - 20 * i, h - 20 * i)
	end
end

function love.draw()
	iterator()
end