Lua Programming Help Thread

[yaustar]

There are sixty Vblanks in a second, so this pauses our program at this point for exactly one second.

That is correct to the PSP's screen as it refreshes at 60hz.

so the vblank is the refresh rate?

No. The refresh rate represents how many times the screen gets drawn per second. Every time the screen is drawn, there is one vblank.

This is why I said you ignored my post. There was a link in brackets that said, "read this" which goes to a Wiki explaining EXACTLY what a vBlank is. Obviously, you didn't read it.

[_dysfunctional]

thanks i'll start from there

and the first link will help me code for psp and use a compiler for psp right? no. I seriously doubt it. Anyways the link above from Art shows BOTH C and lua even though C++ and C arn't the same thing, but I'm pretty sure they're similar. I'll start in lua so I don't need to compile :P

Ok I am just starting and all, my Hello World worked, but is there like a flash application of some sort that lets me click on a color and it will show me the RGB? (0, 0, 255 for blue, for example) because I know there is one in photoshop but that makes my computer lag like hell

EDIT: NVRM what i'm using is microsoft paint - go to colors at the top, click on edit colors, click on define custom colors, and a full RGB table will come up and if you click anywhere it shows you what the RGB values are for that color WHOOHOO yay



Ok the bold, italisized, underlined part above is where I am confused. Here is a copy/paste of what I have done so far

System.usbDiskModeActivate()
pink = Color.new(255, 0 , 153)
blue = Color.new(0 , 153, 255)
orange = Color.new(255, 102, 0)
gray = Color.new(150, 150, 150)
black = Color.new(0 , 0 , 0)
screen:print(194, 136, "Loading: 0%", pink)
screen.flip()
background = Image.load("images/background.jpg")
screen:clear()
screen:print(194, 136, "Loading: 20%", pink)
screen.flip()
circle = Image.load("images/buttons/circle_button.png")
down = Image.load("images/buttons/down_arrow.png")

screen:clear()
screen:print(194, 136, "Loading: 40%", pink)
screen.flip()

l = Image.load("images/buttons/left_trigger.png")
left = Image.load("images/buttons/left_arrow.png")

screen:clear()
screen:print(194, 136, "Loading: 60%", pink)
screen.flip()

r = Image.load("images/buttons/right_trigger.png")
right = Image.load("images/buttons/right_arrow.png")
boltsnd = Sound.load("music/comp.wav")

screen:clear()
screen:print(194, 136, "Loading: 80%", pink)
screen.flip()

square = Image.load("images/buttons/square_button.png")
triangle = Image.load("images/buttons/triangle_button.png")

screen:clear()
screen:print(194, 136, "Loading: 90%", pink)
screen.flip()

up = Image.load("images/buttons/up_arrow.png")
x = Image.load("images/buttons/cross_button.png")
splash = Image.load("images/lua.png")

screen:clear()
screen:print(194, 136, "Loading: 99%", pink)
screen.flip()

screen.waitVblankStart(240)
Music.volume(128)

Now those last two lines were copied from the quote, but he says that we are going to do screen.flip again, so I was thinking if I should make it look like this

screen.flip()
screen.waitVblankStart(24 0)
Music.volume(128)

but then again, that would do a double screen clear which would be pointless to put the same line twice, so should I put it after the screen.waitVblankStart(24 0) and before the music volume? or should I ignore that completely?

EDIT: it is now 3:00 am WHERE I LIVE so I'll go to bed and see if I can get an answer tomorrow. hopefully someone will help me so i can become a good coder in the future. I am not going to post any half-witted lua releases when I learn to code, instead, i am going to see if there are any good ideas, and if there arn't any, then I will switch to C, which I will have a basic understanding of programming applications altogether so learning C will make more sense, or i can try to completely master lua and come up with something three-quarters-witted instead of half-witted (i havn't seen any good lua applicaitons or games at all so i can't expect me to break the barrier of lua vs. C)

My point was that there is no difference from coding C++ for the PSP or any other system besides API specific functions in the PSPSDK. If you don't know C++ at all in the first place, then you will have no clue what you are doing. This stuff takes time, it isn't "Get up and go make a 3D game". Learn the basics and syntax of the language first, then move on the the API specific functions provided by the PSPSDK.

[Mistabeen]

Does anyone know if it's possible to create a rectangle, and fill it but with a semi transparant color
I've tried check = Color.new(100,200,200,50) and check = Color.new(100,200,200,210 ) but it stays the same opacity

and another similar question, is it possible to get a PNG semi transparant, becaus I've loaded a PNG with a gradient transparancy, but it just cuts of at about 50% transparancy, everything below isn't shown, everything over is turned opaque

[Gam3freQ]

My point was that there is no difference from coding C++ for the PSP or any other system besides API specific functions in the PSPSDK. If you don't know C++ at all in the first place, then you will have no clue what you are doing. This stuff takes time, it isn't "Get up and go make a 3D game". Learn the basics and syntax of the language first, then move on the the API specific functions provided by the PSPSDK.

If you can't see already, I have already started to learn lua and learning C++ at this point would only confuse me, so there is no reason for you to continue an arguement for no reason.
-= Double Post =-

That is correct to the PSP's screen as it refreshes at 60hz.


No. The refresh rate represents how many times the screen gets drawn per second. Every time the screen is drawn, there is one vblank.

This is why I said you ignored my post. There was a link in brackets that said, "read this" which goes to a Wiki explaining EXACTLY what a vBlank is. Obviously, you didn't read it.

So the vblank is related to the refreshrate, which is 60hz on the psp, which is why 60 vblanks take a second on the psp, because every time a hz blaublahubadung. In other words, it is the time interval between the end of the last line of one frame or field of a raster display, and the beginning of the next.
-= Double Post =-

if remeber correctly i believe it was:

play:sound(sound name here);

I tried once and it didn't work but will try again

[_dysfunctional]

Not it isn't pointless, and who was arguing? I was just saying that by being rude back to me when I was just trying to help and was correct, is ridiculous.

[Urameshi]

i agree with dys, ridiculous

[Gam3freQ]

Not it isn't pointless, and who was arguing? I was just saying that by being rude back to me when I was just trying to help and was correct, is ridiculous.

I'm sorry, you were right, but I can't even figure out how to play comp.wav in lua so how can I figure out how to do C++:Cry:

[michaelp]

soundvar = Sound.load("sound.wav")

soundvar:play()

Understanding how the pixels in memory are displayed on the screen is important for writing games. The concept of many displays, including the one for the PSP, are the same like for the old cathode ray tube: A beam starts at top left and scans all lines top down. At the bottom it needs some time for returning to the top left, which is called the vertical blank (vblank), because the beam is deactivated while moving back to it’s start position. Of course, in PSP there is no real beam, but you can think of it as if it works like this. With “screen.waitVblankStart() ” the script waits for the start of this vblank. While the vblank time no pixels are written to the display, which gives you the time to flip the screen and offscreen to avoid flickering.

[Gam3freQ]

soundvar = Sound.load("sound.wav")

soundvar:play()

on the first quote - thanks i was able to figure out Sound.load but not how to play it

on the second quote - yes that does help alot - increases understanding of why when I was doing screen.flip() instead of the vblank thing it wouldn't let me press more than one button at a time but now it makes alot more sense thank you for both quotes they really helped we need more people like you around here :Punk:

[michaelp]

you said you want to play comp.wav...

comp = Sound.load("comp.wav") --This loads your sound file
some code
some code
--Now, if you wanted to play the file, you'd do this:
comp:play() --This plays your sound

Also, you only need one "screen.flip" in your script.

[Gam3freQ]

you said you want to play comp.wav...

comp = Sound.load("comp.wav") --This loads your sound file
some code
some code
--Now, if you wanted to play the file, you'd do this:
comp:play() --This plays your sound

Also, you only need one "screen.flip" in your script.

This is what i did and it worked, but if I press the button twice it will play twice over itself

INFO: COMP.wav is in the musc folder, so I put "music/comp.wav" and it worked, then I wanted it to play the sound for every button I press, so I put the complay() under each Pad:variable

Spoiler for my source code:

System.usbDiskModeActivate()
pink = Color.new(255, 0 , 153)
blue = Color.new(0 , 153, 255)
orange = Color.new(255, 102, 0)
gray = Color.new(150, 150, 150)
black = Color.new(0 , 0 , 0)
screen:print(194, 136, "Loading: 0%", pink)
screen.flip()
background = Image.load("images/background.jpg")
screen:clear()
screen:print(194, 136, "Loading: 20%", pink)
screen.flip()
circle = Image.load("images/buttons/circle_button.png")
down = Image.load("images/buttons/down_arrow.png")

screen:clear()
screen:print(194, 136, "Loading: 40%", pink)
screen.flip()

l = Image.load("images/buttons/left_trigger.png")
left = Image.load("images/buttons/left_arrow.png")

screen:clear()
screen:print(194, 136, "Loading: 60%", pink)
screen.flip()

r = Image.load("images/buttons/right_trigger.png")
right = Image.load("images/buttons/right_arrow.png")
boltsnd = Sound.load("music/comp.wav")

screen:clear()
screen:print(194, 136, "Loading: 80%", pink)
screen.flip()

square = Image.load("images/buttons/square_button.png")
triangle = Image.load("images/buttons/triangle_button.png")

screen:clear()
screen:print(194, 136, "Loading: 90%", pink)
screen.flip()

up = Image.load("images/buttons/up_arrow.png")
x = Image.load("images/buttons/cross_button.png")
splash = Image.load("images/lua.png")

screen:clear()
screen:print(194, 136, "Loading: 99%", pink)
screen.flip()

screen.waitVblankStart(240)
comp = Sound.load("music/comp.wav")
Music.volume(128)

while true do
	screen:blit(0, 0, background, false)
	
	pad = Controls.read()
	
	screen:print(135, 251, "Press 'Start' to restart", blue)
	screen:print(110, 261, "Press 'Select' for a screenshot", blue)
	screen:print(383, 35, "Support:", black)
	screen:print(365, 45, "PS3Lounge.net", orange)
	screen:print(365, 55, "scriptscribbler.com/psp", gray)
	
	if pad:cross() then
		screen:blit(50, 228, x)
                comp:play()
	end
	
	if pad:circle() then
		screen:blit(90, 195, circle)
                comp:play()
	end
	if pad:triangle() then
		screen:blit(45, 165, triangle)
                comp:play()
	end
	
	if pad:square() then
		screen:blit(15, 195, square)
                comp:play()
	end
	
	if pad:up() then
		screen:blit(60, 40, up)
                comp:play()
	end
	
	if pad:right() then
		screen:blit(90, 65, right)
                comp:play()
	end
	
	if pad:down() then
		screen:blit(60, 80, down)
                comp:play()
	end
	
	if pad:left() then
		screen:blit(30, 65, left)
                comp:play()
	end
	
	if pad:l() then
		screen:blit(4, 6, l)
                comp:play()
	end
	
	if pad:r() then
		screen:blit(403, 4, r)
                comp:play()
	end
	
	if pad:select() then 
		screen:save("screenshot.tga") 
                comp:play()
	end
	
	if pad:start() then
		break
	end
	
	screen.waitVblankStart()
	screen.flip()

end

[xpack]

if pad:circle() and comp=true then
--Whatever for this
end

I think

[Gam3freQ]

if pad:circle() and comp=true then
--Whatever for this
end

I think

? what? I posted my code above which works

http://wiki.ps2dev.org/psp:lua_player:tutorial
http://www.evilmana.com/tutorials/lua_tutorial_list.php

both links above provide little explanation which I don't like. I feel like I need to :rtfm: but only if I could find the manual

[SG57]

you said you want to play comp.wav...

comp = Sound.load("comp.wav") --This loads your sound file
some code
some code
--Now, if you wanted to play the file, you'd do this:
comp:play() --This plays your sound

Also, you only need one "screen.flip" in your script.

Not necesarily, it depends on the effect you're trying to produce.

Run this script hten look at it and you'll see
http://jordansg57.googlepages.com/Tr...ionCircles.lua

[Da_MerV]

hmm thats weird, my latest project has semitransparent colors that blit perfectly. is it the darker half of the png that gets cut off?
-= Double Post =-
btw, nevermind my question on text width, i found something on the ps2dev forums that answered my question. looks like he had the same problem...

I already found out myself: I forgot the quotation marks. Should be
Code:
ActFont:getTextSize(Bonus TXT[LastB+1])["width"]


for the height, you probably need ["height"]

[Gam3freQ]

http://dl.qj.net/PSP-LUA-Software-St...3462/catid/193
Will this help me code? I have downloaded it... because it says that it will help debug... but I have no idea on how to use it as the readme is a 0kb file...

[almost219]

it has basic coding help, but nothing too technical

[Gam3freQ]

Not necesarily, it depends on the effect you're trying to produce.

Run this script hten look at it and you'll see
http://jordansg57.googlepages.com/Tr...ionCircles.lua

I'm not good enough to be compared at all with SG57, so that's besides the point
-= Double Post =-

it has basic coding help, but nothing too technical

I can't even use it properly. when I click debug it launches a pc version of luaplayer. and I don't know the pc controls either. I don't get why it has a compiler because you can't compile lua. I don't understand the usage of "quick notepad" in this application either, so I guess I'm better off without this and using notepad

[KleptoOne]

Does anyone know if it's possible to create a rectangle, and fill it but with a semi transparant color
I've tried check = Color.new(100,200,200,50) and check = Color.new(100,200,200,210 ) but it stays the same opacity

and another similar question, is it possible to get a PNG semi transparant, becaus I've loaded a PNG with a gradient transparancy, but it just cuts of at about 50% transparancy, everything below isn't shown, everything over is turned opaque

are you testing your app on your psp or are you using windows luaplayer? windows luaplayer does not handle transparencies correctly.

[SG57]

Nor Lua Player itself. I believe you can't make a half transparent rectangle without it being an image. It's either 100% transparent or 0%.

[FaT3oYCG]

wtf r u all talkin about if you want to make an IMAGE transparrent then you have to do this screen:blit(0, 0, image, transparency in %)

you cant create a colour with transparrency you have to apply it to the image

i dont know if it works for image.createempty() or rect.createempty() shapes but if u want that then just make an image the size you want and apply transparrency to that

[Grimfate126]

windows luaplayer isnt compatible with transparent images. it the image is anything more than 0% transparent, windows luaplayer shows the image as if it werent transparent.

[Mistabeen]

I know I should have tested it on my psp more, but when it are such trival changes you just check them on your computer :)
thanks for the help tho

got another problem tho, can I resize an image to a variable size?
I found something on Evilmana but that uses a fixed size te resize it to, what I want to do is change the size constantly to whatever my variable tells it to be

the other small thing is that I need to rotate an image on a buttonpress, the rotation is so subtle that using images would require about 200 different images, wich would be a bit to much, how do I do this in LUA? I think it uses the 3D GU rotate function, but I can't find any relevant information on that.

[michaelp]

Not necesarily, it depends on the effect you're trying to produce.

Run this script hten look at it and you'll see
http://jordansg57.googlepages.com/Tr...ionCircles.lua

I see.
And, the compile feature probably makes a "Game and Game%" folders so you don't need luaplayer to test it on your PSP.

Also, Lua can be compiled.(Prevents source from being read, small speedup. Useless for small scripts.)

[Gam3freQ]

I see.
And, the compile feature probably makes a "Game and Game%" folders so you don't need luaplayer to test it on your PSP.

Also, Lua can be compiled.(Prevents source from being read, small speedup. Useless for small scripts.)

Regaurdless, even though I have some basics of lua, I could never program one bit without a tutorial teaching me how to do something (as in code the whole thing by hand). I understand the BARE BONES basics (BBB) of the language but it isn't good enough to be a second language; I need to be fluent in the language like it was my second language; be able to type it, speak it, and know it, but I can only read it BBB style, not even understand fully. I need a tutorial that gives a great understanding and a cheat sheet to help me code, and a bunch of functions that work and how to use them correctly, which I know there must be somewhere on the internet.

[FaT3oYCG]

one site and one site only when it comes to the more advanced stuff there arent any tuts u have to look at other peeps code and figure it out urself

site:
http://www.evilmana.com/tutorials/

[michaelp]

finish the tutorials at evilmana first (click on the link the last poster gave you)
i can now understand lua, and i used to be bigger noob than you
here's what happened
I started to learn Lua, and eventually made a script that blitted specific images when you pressed a button. I thought "Oh, this is easy, I'm gonna try to learn C since it's more powerful than Lua and it will help in the long run".
Bad idea.
I looked at the tutorials at psp-programming. I got to the 5th one until I said: "Wow. This is too hard, and I suck at it. Time to stop programming."
So, for about a month or so (give or take a bit) I started to learn Lua again.
I still had all the tutorials I found on the internet in .txt files, so I used those, got some more from evilmana, and picked up Lua and thought "How didn't I understand this before?"

I'm not saying you should go through the same process, I'm saying that one day, something just "clicked" and I understood it all. Just keep using some tutorials, and you'll understand soon enough.

[FaT3oYCG]

about the resize thing that would be a long piece of code even just for 2 sizes but i could tell you how to do it if u be more specifc and tell me what you need it for and weather it is on a button press and wether you want it to have a menu

[FaT3oYCG]

good advice dude

EDIT:

there are three steps

1. figure out what you need to tell the psp to do first
2. tell yourself in english or american how it is done e.g. load the image then put it on the screen
3. learn what the functions do so you know when to use them

[Gam3freQ]

Thanks for all the help. I will be spending alot of time at evilmania now. Michaelp, I thought that eventually it would click and everything would make perfect sense, but it hasn't happened yet, so I will try to master lua (no wannabe applications are going to released)

However, when I start to learn more about lua, I think that this would be a fairly challenging start to try to clone/port this http://scarymonkey.net/Flash/batmouse.swf but maybe that is too chalenging because of the AI, but this would be alot easier http://scarymonkey.net/Flash/squares.swf I think, because there is only one level and EVERYBODY loves squarez so everybody would love to see a squares 2 or for a start maybe fishy http://www.xgenstudios.com//fishy/fishyxgen.swf