Requesting Help - INTROS

[JamiezRascall]

Ok so how would I go about making a intro with a image which would fade to the main menu?
Also am a newbie, How do I create new frames and transition to them?

[TechnoCat]

Draw the image with a full alpha on the screen after you draw the main menu. Then use dt to subtract from the alpha over a period of time. Sorry this is so high level, but maybe this helped.

The key function here is love.graphics.setColor(). setColor not only controls the color, but the alpha too.

Code: Select all

function love.load()
	image = love.graphics.newImage("girl.jpg")
	alpha = 255
end

function love.update(dt)
	if alpha > 0 then
		alpha = alpha - 40*dt
	else
		alpha = 0
	end
end

function love.draw()
	love.graphics.setColor(255,255,255,255)
	love.graphics.print("MAIN MENU\nMAIN MENU\nMAIN MENU\nMAIN MENU",24,24)
	love.graphics.setColor(255,255,255,alpha)
	love.graphics.draw(image,0,0)
end

[JamiezRascall]

so say if I never had logo of the studio appear with that which works but if then I want the logo to appear from 0 alpha to 255 would I use ?

Code: Select all

if(Logodraw > 255) then
   Logodraw = Logodraw + 40*dt
   else 
       alpha = 255
 end
end

Currently here is my full game

Code: Select all

function love.load()
 love.graphics.setBackgroundColor(255,255,255)
 CompanyLogo = love.graphics.newImage("CompanyLogo.png")
 alpha = 255
 MenuFont = love.graphics.setFont("FutureMillennium.ttf",12)
 Soundtrack = love.audio.newSource("Soundtrack.mp3", "Stream")
 love.audio.play(Soundtrack)
end

function love.update(dt)
 if(alpha > 0) then
   alpha = alpha - 40*dt
    else
        alpha = 0
    end
  end
 if(Logodraw > 255) then
   Logodraw = Logodraw + 40*dt
   else 
       alpha = 255
 end
end

function love.draw()
--//StartingIntro
 love.graphics.setColor(255,255,255,alpha)
 love.graphics.draw(CompanyLogo,280,80)
 love.graphics.setColor(0,0,0,alpha)
 love.graphics.print("We're Gamers too.",330,280)
--//FinshedIntro
 logo = love.graphics.newImage("GT_G-Logo.png")
 love.graphics.draw(logo,185,140)
end

[Jasoco]

You'll also need timing so that the menu doesn't appear until after the logo is gone.

The way I do it is the first say 7.5 seconds of the game runtime is the logo intro. When love.timer.getTime() > 7.5 then it changes the "gameMode" from 1 to 2 (Or whatever).

Inside my update and draw functions of course I have if then else conditions checking what the "gameMode" is and displaying the appropriate stuff. "gameMode" starts at 1 for "intro" and changes to 2 when the timer reaches 7.5. This is just an example to get you started.

And as TechnoCat said, dt is good for making stuff animate smoothly and in time. Basically you'd have the number of "whatevers" per second times Delta (td). Like if you want a character to move at a speed of 256 pixels per second, you'd do 256 * dt. So if you had it move, it would take 1 second to move 256 pixels. It works for whatever. Not just movement but timing too.

[Luiji]

Why dt as supposed to delta? I mean, you can name it whatever you want in the callback, so why not rename it for documentation purposes?

[TechnoCat]

Why dt as supposed to delta? I mean, you can name it whatever you want in the callback, so why not rename it for documentation purposes?

dt stands for delta time, and as far as I'm concerned it is the normal practice here.

[Jasoco]

Also, dt is just shorter and easy to remember. I actually pass it into my love.draw function too because my game requires some drawing stuff take advantage of delta as well. Which is why I love that I can customize the love.run function myself.

[bartbes]

Of course there's always love.timer.getDelta() that you can call in love.draw.
To answer why dt, because it is a standard name.

[Robin]

so say if I never had logo of the studio appear with that which works but if then I want the logo to appear from 0 alpha to 255 would I use ?

Code: Select all

if(Logodraw > 255) then
   Logodraw = Logodraw + 40*dt
   else 
       alpha = 255
 end
end

Also, you'll have more luck if you change Logodraw > 255 to Logodraw < 255.

[Jasoco]

Well, since I just put dt in the parenthesis for love.draw right in the custom love.run it works just as well as it does in love.update which also gets its dt from love.run.

This is my love.run(), isn't it beautiful?

Code: Select all

function love.run()
	screenModes = love.graphics.getModes()
	if love.filesystem.exists("game/audio/") == false then enableAudio = false else enableAudio = true end
	firstRun = false
	if love.filesystem.exists("conf.lua") == false then
		local sw = 640 sh = 480
		createConfiguration(sw, sh)
		local _ = gr.setMode(sw, sh, false, true, 0)
		firstRun = true
	end
	love.load(arg)
	local dt = 0
	while true do
		ti.step()
		time = ti.getTime()
		dt = ti.getDelta()
		if dt > .2 then dt = .2 end
		love.update(dt)
		gr.clear()
		love.draw(dt)
		if love.event then
			for e,a,b,c in love.event.poll() do
				if e == "q" then
					if love.audio then love.audio.stop() end
					return
				end
				love.handlers[e](a,b,c)
			end
		end
		ti.sleep(1)
		gr.present()
	end
end

Timer is placed in ti, Graphics is placed in gr. Confining dt to less than .2 was a way of trying to stop the occasional accidental "get stuck in walls" bug that kept happening occasionally when the game would freeze for a second due to processor hiccups. Not sure it fixed it though. It should probably be .02 instead, but since it rarely happens I can't test reliably. My audio functions are called if the Audio folder exists, which it doesn't when this is a demo uploaded since I leave audio out of the .love file to save bandwidth. It also creates a preference file on first run. If one doesn't exist it is considered the first run.