Getting the center coordinates of the screen?????

[RBXcpmoderator12345]

I am trying to draw a image that stretches to the size of the screen. I can use the getWidth and getHeight and the paramaters of the draw function to do that, but I want it to be at the center of the screen so the image isn't offscreen.

[arampl]

First translate x = - imagewidth / 2, y = -height / 2, then scale, then translate x = screenwidth / 2, y = screenheight / 2.

Sorry. This is wrong. Please give me a moment.

[RBXcpmoderator12345]

Um... what?

This is my code, if it helps:

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function love.draw()
if playing == false then
love.graphics.draw(titlescreen)
love.audio.play(theme)
love.graphics.printf("Press Q to play.",75, 350, 200,"center") -- center your text around x = 200/2 + 100 = 200
elseif playing == true then
love.graphics.draw(background, otherParametersHere) -- A
love.audio.stop(theme)
end
end

yes everything is defined
im just having problems with the line with the comment "a"

[arampl]

To center text:

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function love.load()
-- some of your loading code goes here...

	offw, offh = love.graphics.getDimensions()
	text = "Press Q to play."
	limit = 75
	font = love.graphics.getFont()
	h = font:getHeight()
	_, lines = font:getWrap(text, limit)
	x, y = offw / 2 - limit / 2, offh / 2 - h * lines / 2

-- rest of your loading code goes here...
end

function love.draw()
	love.graphics.printf(text, x, y, limit,"center")
end

You shouldn't put audio code in love.draw(). Put it somewhere else. See my example in your topic "How do I remove drawn images & printed text?"

Kingdaro already told you how game loop is organized.
Normally (if vsync is on), love.draw() function called 60 times per second! Therefore, you should keep all unneeded stuff outside of it. But you keep calling audio.play / audio.stop 60 times per second. Maybe it's harmless to try to play already plaiyng / stop already stopped music, but CPU cycles wasted nevertheless.

[zorg]

Normally (if vsync is on), love.draw() function called 60 times per second! Therefore, you should keep all unneeded stuff outside of it.

Correction: It is called depending on the current screen's set refresh rate; that can be anything the monitor supports, but it's usually between 60 and 120; example: mine's 75Hz, so love.draw would be called 75 times a second instead of 60.

By the way, love.update would be called the same amount of times love.draw would (under the default circumstances that is (default love.run)), but your're right, it doesn't really go into love.draw.

Edit: to answer the OP's question:

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love.graphics.draw(background, love.graphics.getWidth() /2 - background:getWidth() /2, love.graphics.getHeight() /2 - background:getHeight() /2) -- untested but should work

[arampl]

Correction: It is called depending on the current screen's set refresh rate; that can be anything the monitor supports

Yeah, you're absolutely right. My bad.

Edit: to answer the OP's question:

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love.graphics.draw(background, love.graphics.getWidth() /2 - background:getWidth() /2, love.graphics.getHeight() /2 - background:getHeight() /2) -- untested but should work

It appears that things are much simpler than I've thought. To "draw a image that stretches to the size of the screen" enough would be just:

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love.graphics.draw(background, 0, 0, 0, love.graphics.getWidth() / background:getWidth(), love.graphics.getHeight() / background:getHeight())

[RBXcpmoderator12345]

I know, I figured that out.
My problem is this;
I am trying to center the picture. Whenever i try to position it, it is either offscreen or partially offscreen.
Yes, it is the full size of the screen because

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

This is my code:

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love.graphics.draw(background, 672, 372, 0, width, height, 672, 372)

[arampl]

Well, what is the actual size of your background image (and window size, to be sure)?

1.Do you have background image that is smaller than screen size?
2. If that is so, do you want just center it unscaled or scale it to the screen size, retaining its aspect ratio?

This code will stretch image of any aspect ratio to the screen size of any aspect ratio (will be centered and retain image's aspect ratio, of course):

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	w, h = love.graphics.getDimensions()
	bw = background:getWidth()
	bh = background:getHeight()
	if bw / bh > w / h then
		scale = w / bw
		x = w / 2 - bw / 2 * scale
		y = h / 2 - bh / 2 * scale
	else
		scale = h / bh
		x = w / 2 - bw / 2 * scale
		y = h / 2 - bh / 2 * scale
	end
	love.graphics.draw(background, x, y, 0, scale, scale)

[TheOddByte]

If it helps, this is what I use

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local image = love.graphics.newImage( "<path>" )
local w, h = love.window.getDimensions()
local width, height = image:getDimensions()
local scalex, scaley = w/width, h/height

function love.draw()
    love.graphics.draw( image, 0,0,0, scalex, scaley )
end

That code basically stretches an image to fit the whole screen, here's how you can center an image

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local image = love.graphics.newImage( "<path>" )
local w, h = love.window.getDimensions()
local width, height = image:getDimensions()

function love.draw()
    love.graphics.draw( image, (w-width)/2, (h-height)/2 )
end

[RBXcpmoderator12345]

ok thanks