Lua Programming Help Thread

[yotop456]

alright awsome

[gameo]

Allright, BlackShark helped me before, but im afraid it didn't work.
I need this:

if pad:cross() and (collosion with my cursor, and my button here) then
(blit my new image, as a new menu will pop-up)
end

But i don't have good memories with collosion... (My crappy Ping Pong game...)

So can anyone help me here? I need from Start to End instructions, because i just don't get it sometimes.

[TacticalPenguin]

Here's a simple click function I made for a shell a while back:

function click(ob)
if pad:cross() and (cursor.x > ob.x) and (cursor.x < ob.x + ob.w) and (cursor.y > ob.y) and (cursor.y < ob.y + ob.h) then
return true
else
return false
end
end

You'll just have to add w and h variables to the items that are clickable. Then you can use it like this:

if click(nameofobjectyou'red etectingaclickfor) then
*stuffthathappenswhenitis clicked*
end

[gameo]

Allright, it'll go like this properbly, and ill show what i didn't understand:

function click(menu) -- which is my button

if pad:cross() and (cursor.x > menu.x) and (cursor.x < menu.x + menu.w --? is the the width or something?) and (cursor.y > menu.y) and (cursor.y < menu.y + menu.h -- ?, is that the height or something?) then
return true -- return is not supposed to be there, is it?
else
return false -- Look up.
end
end

And then:

if click(menu) then
screen:blit(where it is, where it is, start, false)
end

[GuitarGod1134]

Are there any tutorials in Lua for reading entire text files and printing them to the screen or can someone help me out on pg 505?

[Anti-QuickJay]

y = 10					
file = io.open("testRead.txt","r")					
for line in file:lines() do
y = y + 10
screen:print(100,y,line,white)
end					
file:close()

http://evilmana.com/tutorials/lua_tutorial_09.php

[BlackShark]

Allright, it'll go like this properbly, and ill show what i didn't understand:

function click(menu) -- which is my button

if pad:cross() and (cursor.x > menu.x) and (cursor.x < menu.x + menu.w --? is the the width or something?) and (cursor.y > menu.y) and (cursor.y < menu.y + menu.h -- ?, is that the height or something?) then
return true -- return is not supposed to be there, is it?
else
return false -- Look up.
end
end

And then:

if click(menu) then
screen:blit(where it is, where it is, start, false)
end

the return true IS suppost to be there, thats how you know if the cursor is in the button, in there, you make an if statement like "if pad:cross() and click(menu) == true (not sure if click(menu) is supposed to be like that but hey, im not so hot in collision niether) then
do your if statement functions, here like load this or do that
end

give that a try, but again, no make sure's it will work (said "make sure's cuz i cant spell garrentie!)

[TacticalPenguin]

The return true/return false is used for telling whether the conditions are true or not AKA whether its been clicked.

w and h are width and height

So use it like this:

menu = {x = something,y = something, w = widthofmenuimage, h = heightofmenuimage}

function click(ob)
if pad:cross() and (cursor.x > ob.x) and (cursor.x < ob.x + ob.w) and (cursor.y > ob.y) and (cursor.y < ob.y + ob.h) then
return true
else
return false
end
end


while true do
pad = controls.read()
screen:clear()
screen:blit(menu.x,menu.y ,menuimg)
screen:blit(cursor.x,curs or.y,cursorimg)
*otherstuffofrcursormovem ent*
if click(menu) then
*stuff you wanna do when menu is clicked*
end
screen.waitVblankStart()
screen.flip
end

[PSPhakkor]

Does anyone know if it's possible to rotate an image being displayed on the screen? Thanks. Hopeing to get a reply...:Punk:

[emericaska8r]

Does anyone know if it's possible to rotate an image being displayed on the screen? Thanks. Hopeing to get a reply...:Punk:

i think i saw something like that on evilmana or something, but i have no time to look right now... sorry
-= Double Post =-

ok i have two questions,

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.someext ensi on" then
*whatever you wanna do when it finds it*
end
end
end

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

thanks for any answers

can someone give me information about this? thanks

[Grimfate126]

Does anyone know if it's possible to rotate an image being displayed on the screen? Thanks. Hopeing to get a reply...:Punk:

there is, but its buggy, and will drop your framerate below 30. so, look for better means to do it.

[Cheez Pirate]

y = 10					
file = io.open("testRead.txt","r")					
for line in file:lines() do
y = y + 10
screen:print(100,y,line,white)
end					
file:close()

http://evilmana.com/tutorials/lua_tutorial_09.php

pspsgamer... I'm pretty sure you had 1,100 posts only last month. It says you post an average of 18 a day... Are you ok?

[SG57]

Grimfate - One way would be to use the GU and rotate a textured quad, the texture being the image you want to rotate.

[HeaD_ShOt]

i keep getting the error:
wrong number of arguments
here is the code

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: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
end

if pad:up() and oldpad:up() ~=pad:down() then
current = current - 1
end

if pad:down() and oldpad:down() ~=pad:down() then
current = current + 1
end

if current == 0 then
current = 3
end
if current == 4 then
current = 1
end

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

[TacticalPenguin]

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

No xy coordinates.

[SG57]

Itd help immensly if you gave us a line number...

Until then, try adding some X and Y coordinate values to lines 20,23 and 26.

EDIT

Weird, my thing didnt show someone already answered...

[emericaska8r]

can someone answer my post at the top please?

[Yongobongo]

Anyone know some good AI tuts?
Also, can anyone help me with using netlib? I REALLY need both these things :)
Thanks to anyone who can help me out ;)

[TacticalPenguin]

I havent written any games with netlib but I do know how to use it if you need help.

[yaustar]

Anyone know some good AI tuts?

Here is a start. Look around Gamedev for more or get a good book: http://www.gamedev.net/reference/art...article784.asp

[Yongobongo]

I havent written any games with netlib but I do know how to use it if you need help.

You do? Great :) I'll PM you when i need you :)
Thanks Tactical!

[pspfreak9]

Hey yoyobongo try this site: (it shows you how to make a infastructure game with netlib.)
http://www.cools.biaklan.com/Tutorial/netlibtut.html

[Yongobongo]

Thanks, ill have a look at it :)

[Cheez Pirate]

Is there a limit in Lua on how many images you can load? In my index.lua I can only load 13 images... Any more and i'll get an error that it can't load it. They're all 480x272.

[yaustar]

The limit is the amount of memory you have available for LuaPlayer, the large the image, the more memory you take up.

[Cheez Pirate]

Well maybe i dont need an image anymore? How do I delete it from RAM or wherever it goes when I preload it.

[Grimfate126]

Well maybe i dont need an image anymore? How do I delete it from RAM or wherever it goes when I preload it.

name_of_image = nil

that will free the memory.

and, 13 480x272 images is WAYYY too much. you wont even be able to load 6 detailed ones.

[TacticalPenguin]

nameofimage = nil will clear it from ur ram. same goes for anything else
-= Double Post =-
whoa thats odd i didnt see grimfates post

[Cheez Pirate]

Hey thanks TacticalPenguin

[eyece]

this is more of a general programing question, but how do you get the angle and distance between 2 points, (x1,y1,x2,y2).