Lua Programming Help Thread

[the undead]

ok so, ive been reading up on files and what not but i cant find anything usefull that i need. im trying to make it were i have a string like

name = "The undead"
search = name

--and search funtion would be here like
search1 -- and then search stuff....

and i want to search for a file named wehat ever is in the string, then open that file and read it. but i cant figure out how to do this, ive spent months looking....

[SG57]

the_undead, there is no function for that at your disposal right now. But, you can easily make it.

You'd need to make it recursively scan each directory on the memory stick for a file name with the string specified, and if found - try to open it with read-only permission.

Or something similar Im sure...

[the undead]

the_undead, there is no function for that at your disposal right now. But, you can easily make it.

You'd need to make it recursively scan each directory on the memory stick for a file name with the string specified, and if found - try to open it with read-only permission.

Or something similar Im sure...

how would i make it?.....sorry if i ask to many questions im just eager to learn new things.

[TacticalPenguin]

Ill give you an example to scan a single directory:

files = System.listDirectory()
for i = 3, table.getn(files) do
if not files[i].directory then
if files[i].name == "somefilename.someextensi on" then
*whatever you wanna do when it finds it*
end
end
end

[the undead]

Ill give you an example to scan a single directory:

files = System.listDirectory()
for i = 3, table.getn(files) do
if not files[i].directory then
if files[i].name == "somefilename.someextensi on" then
*whatever you wanna do when it finds it*
end
end
end

ok thats basicaly what i needed, ill try it. its not exact but ill change some stuff.

[emericaska8r]

Ill give you an example to scan a single directory:

files = System.listDirectory()
for i = 3, table.getn(files) do
if not files[i].directory then
if files[i].name == "somefilename.someextensi on" then
*whatever you wanna do when it finds it*
end
end
end

ok i have two questions,

1 - why did you start the for loop at 3?
2 - what does (if not file[i].directory) do?

thanks for any answers

[yotop456]

hi i have a few problems that i cant seem to figure out.

can someone tell me if there is a code to unload .wav files? because i seem to run out of memory when i load more then 4 of them ( there very short and small in size).

also when you dofile a script, is the script that is being dofiled being executed over the script before it, meaning the script remains loaded in the memory while the new script is loaded?

Thanks

[the undead]

hi i have a few problems that i cant seem to figure out.

can someone tell me if there is a code to unload .wav files? because i seem to run out of memory when i load more then 4 of them ( there very short and small in size).

also when you dofile a script, is the script that is being dofiled being executed over the script before it, meaning the script remains loaded in the memory while the new script is loaded?

Thanks

try

wavfile = nil

thats all you do

[GuitarGod1134]

hi i have a few problems that i cant seem to figure out.

can someone tell me if there is a code to unload .wav files? because i seem to run out of memory when i load more then 4 of them ( there very short and small in size).

also when you dofile a script, is the script that is being dofiled being executed over the script before it, meaning the script remains loaded in the memory while the new script is loaded?

Thanks

wav = song.wav

wav = nil

all done

as for dofiles

dofiles are like this
say your script is like this

while true do
screen:print(0,0,"I like cake a lot",red)
dofile("bla.lua")
screen.waitVblankStart()
screen.flip()
end

and in the dofile you have

screen:print(0,10,"BUt i also like donuts",red)

then according to the psp and lua player this is what script is

while true do
screen:print(0,0,"I like cake a lot",red)
screen:print(0,10,"BUt I also like donuts",red)
screen.waitVblankStart()
screen.flip()
end

-= Double Post =-
Ok im trying to get my tab reader working and im trying to print all the lines of a tab to the screen from a text file named tab.txt and its not working. So far here is my code

--declare some colors and whatnot
blue = Color.new(0,0,255)
red = Color.new(255,0,0)
background = Image.createEmpty(480,272)
background:clear(blue)
--main loop
while true do
screen:blit(0,0,background)
--now lets read the tab
y = 5
file = io.open("tab.txt","r")
for line in file:lines() do
y = y + 5
screen:print(0,y,line,white)
end
file:close
screen.waitVblankStart()
screen.flip()
end

And here is whats inside my text file
named tab.txt

-3---3--------------2-0-------|
-3-----3---3------3-----3---3-|
-0-------0------2---------2---|
-0------------0---------------|
------------------------------|
-3----------------------------|

Im trying to get scrollign to work also if someone could help me there too. and one more thing this line

file = io.open("tab.txt","r")

What is my tab is in a certain directory wouldnt it be

file = io.open("./tab/tab.txt","r")

right?

Could use some help.
-= Double Post =-
O yah adn the error im getting is like something wrong with the argument screen on line 20 or somethign

[emericaska8r]

can someone look on the page before for my question?

and for guitargod, i don't see anything wrong with that code to read the lines, but i just want to let you know that instead of defining background as an image, and clearing it, and then blitting it; you could just do screen:clear(blue)

and let us all know what you need exactly for scrolling
-= Double Post =-
wait, i don't know if this is right, but could you do:

for 0,  line in file:lines() do

[GuitarGod1134]

like when you press down it scrolls down the lines of text that are being read from the file.

[ZereoX]

Hi does anyone know how to do a Typewriter effect?

[Anti-QuickJay]

http://evilmana.com/tutorials/codeba...ter_effect.php

[HeaD_ShOt]

i cant seem to figure out y none of the menus i have coded work
here is my code

--Quick Japanese
--By Cheese the psp
--Thank you to all those that have writen a tutorial

System.usbDiskModeActivat e()

white = Color.new(255,255,255)
red = Color.new(255,0,0)

current = 1
oldpad = Controls.read()
while true do
pad = Controls.read()
screen:clear()

screenrint(10,10,"Quick Japanese",white)
screenrint(10,20,"by Cheese the Psp, from the QJ forums",white)
screenrint(192,95,"Categories", white)
screenrint(192,105,"Alphabet",w hite)
screenrint(192,115,"Usefull Phrases",white)
screenrint(192,125,"Dictionary" ,white)

if current == 1 then
screenrint("Alphabet",red)
end
if current == 2 then
screenrint("Usefull Phrases",red)
end
if current == 3 then
screenrint("Dictionary",red)
end

if pad:up() then
current = current - 1
if current == 0 then
current = 3
end
end

if pad:down() then
current = current + 1
if current == 4 then
current = 1
end
end

if pad:cross() then
if current == 1 then
dofile("alphabet.lua")
elseif current == 2 then
dofile("usefullphrases.lu a")
elseif current == 3 then
dofile("dictionary.lua")
end

screen.waitvblankStart()
screen.flip()
oldpad = pad
end
end

[Anti-QuickJay]

i cant seem to figure out y none of the menus i have coded work
here is my code

You will see your problems when you compare your code to this,
http://evilmana.com/tutorials/codebase/simple_menu.php
Also, You should try this

if pad:cross() and current == 1 then
     dofile("alphabet.lua")
end

Also, Where is this suppose to screenprint?

if current == 1 then
screen:print("Alphabet",red)
end
if current == 2 then
screen:print("Useful Phrases",red)
end
if current == 3 then
screen:print("Dictionary" ,red)
end

You forgot the coordinates.

[EminentJonFrost]

its supposed to be:

dofile("./file.lua")

you didnt put these: ./

[Anti-QuickJay]

its supposed to be:

dofile("./file.lua")

you didnt put these: ./

Since when do you have to do that? I neve have to do it.

[HeaD_ShOt]

u dont have to put those in

[Anti-QuickJay]

Yea, i thought so.

[yotop456]

hey

for my program i have an image 2300 pixels in hight, and 200 pixels in width. I need this picture to scroll down the screen vertically at a speed i chose,

does anyone no any code that would allow me to do this?

thanks

[TacticalPenguin]

You need to first of all divide it into increments smaller than 512x512.

[yotop456]

k then what do i need to

[BlackShark]

blit them scrolling down, if one goes off the bottom of the screen, blit it above the screen.

[TacticalPenguin]

Yea use a variable and then blit them based off the variable. Then icrease/decrease that variable.

[PSPhakkor]

I need to know how to get the color of a pixel. I am using the code:

check=screen:pixel(checkx, checky)

and when I run the program, the error is "An argument was incorrect"

So I'm probably not using the pixel command correctly. If I wanted to check if the pixel at (checkx, checky) has RGB values of (255, 255, 0) How would I do that? would I have to try:

check=color.new(screen:pixel(checkx, checky))
if check==(255, 255, 0) then
... end

Is that how to do it? I doubt that...

Please help me!
-= Double Post =-

hey

for my program i have an image 2300 pixels in hight, and 200 pixels in width. I need this picture to scroll down the screen vertically at a speed i chose,

does anyone no any code that would allow me to do this?

thanks

If you still need the exact code:

imageY=0
image=Image.load(imagelocation)
for imageY=0, 2300, 1 do
screen:blit(0, imageY, image)

and to change the speed, just change the "1" in the line "for imageY..."

I hope I did that right. I'm still new to this:dj:

[jamz1825]

grass = Image.load("menu.png")

while true do

screen:clear()

screen:blit(0, 0, grass)

screen.waitVblankStart()
screen.flip()
end


y wont that work please help

[PSPhakkor]

You're clearing the screen on every loop, so you can't really see your image. Try this instead:

grass = Image.load("menu.png")
screen:clear()
while true do



screen:blit(0, 0, grass)

screen.waitVblankStart()
screen.flip()
end

[jamz1825]

ah never mind the problem is i dont have enough memory for all my images.
is there a way to solve this.

the images that are taking up the space are only viewed when x is pressed or w/e is there a way around this

[SG57]

jamz1825 - Yes. Think logically about this first though... Theres 2 ways I see to work... One - combine the images into a sprite sheet (probably your easiest method) and use offsets to blit them from certain images.

Two - when X is pressed, load the image and blit it at the same time, but you;d need that old pad thing so it only would load the image once, while still blitting the image if held down (so 2 if pad:cross, one with the oldpad, one without). Then, you could free the image once cross is let go. This would be the best way to be memory efficient, but not so much framerate and whatnot, as that means each time you press X and let go, it would load the image, display it, then free the image, so if you pressed X again, itd do it all over again. Does anyone have a different way then the 2 i listed?

[emericaska8r]

u dont have to put those in

the reason he thought so was because on earlier versions of lua you did have to put them in.