Lua Programming Help Thread

[SG57]

Yes, set a bool...

-- Note, I dont know LUAs syntax 100%, but I do understand the 'coding' 
--concept very well IMO, AKA LUA isnt C, so if you see C syntax, just ignore it ;)
run = false

while true do
    if run~=true then 
        function_needed_to_run_once_here()
        run = true
     end
end

... SG57... out!

[mark.sparky]

ok thanks. How did i not think of that

[SG57]

'Your young and naieve...' lol, jk... Id be a hypicrit for such a thought ;)

[mark.sparky]

dont worry i am only 12 so yeah i am young

[SG57]

I am only 14, and I get judged/treaed differently then the average... I want to say 16 ish coder... Most are around there Im assuming.

[mark.sparky]

hey is there a way to make the controls less sensitive because sometimes when you press x it goes straight through two scripts because the game thinks i pressed it twice

[Bronx]

yeah add a

screen.waitVblankStart(10)

somewhere in you code. remember each number in that is a millisecond.
Also you could incorporate a timer, but thats the hard way ;)

[Branin]

i had this problem too , i put pad = oldpad in the function and it worked for me... i could be wrong so dont get mad if it dosent work out..
-= Double Post =-
is that even remotely right? check my above post.. sorry for the double post if it dosent merge it.

[Jeremy1026]

hey is there a way to make the controls less sensitive because sometimes when you press x it goes straight through two scripts because the game thinks i pressed it twice

have it be

if pad:cross and oldpad ~= pad then
--your code
end

oldpad = pad

[mark.sparky]

ok thnx

[pspsalv2]

if anyone could i would like to know how to fix a problem with my fps cause it slows down when i blit a background and since i screen clear whenever the player moves or jumps it slows down with the background in but without it its perfect:Argh: please help.....thanks

[Branin]

@mark.sparky

Nice Game! Actually seeing how hard lua can be i have a differant outlook on LUA coders.. i know that took alot of work so... good job!

[vettefan]

if someone could help me with a problem I'm having.

I'm trying to make a game, and have everything I need already done, except I need to be able to get the color of certain pixels as the game goes on.
I tried using

Color image:pixel(x, y)

buit had to change it to screen:pixel, instead of image:pixel before it would do anything.

what I want to know is, is it possible to get the r,g,b,a values out of the table made with that function and put the values into variables.

[SG57]

How did you try to use it? That function right there returns a color strctured like:

Color.new(r,g,b)

So make a variable = imageixel(x,y) If this isnt what u were saying, sorry but i didnt quite understand..

[vettefan]

edit- nvm I figured it out and fixed it.

but is it possible to extract the color values from a color?
for example can I extract the Blue value into a variable?

[SG57]

Yes im sure it is... Id need to look at the pixel function in LUA players source though, as i may make it into a structure and easily extract the blue data from it...

[vettefan]

I think I have something that does what I need it to.


thanks for the help though, I was getting something with the pixel colors wrong, now everything's fine :Jump:

[mark.sparky]

Hey what does this erorr mean. "<eof> expected near 'end'" .
Any help would be useful

[Grimfate126]

Hey what does this erorr mean. "<eof> expected near 'end'" .
Any help would be useful

usually (for me) it means that u have an exta a "end" in ur code.

im not 100% sur tho.

[mark.sparky]

thnx. The code thought there was an extra end because i didnt declare the function

[Grimfate126]

thnx. The code thought there was an extra end because i didnt declare the function

no prob.

BTW, is there any command that gives u how many sub-sets are in an array??

E.g.:

bob = {}

bob[1] = "joe"
bob[2] = "zOMG"
bob[3] = "can we build it??"

the array "bob" would have 3 sub-sets.

[SG57]

In C, the equivalent is the 'sizeof' operator...

char bob[3] = { 'S','G','5','7' };
int bob_size = (sizeof(bob));

VERY useful when allocating memory (for me, i need it alot for my 3d texture loading...)

So if ther eis a LUA equivalent, you got it ;)

[Grimfate126]

In C, the equivalent is the 'sizeof' operator...

char bob[3] = { 'S','G','5','7' };
int bob_size = (sizeof(bob));

VERY useful when allocating memory (for me, i need it alot for my 3d texture loading...)

So if ther eis a LUA equivalent, you got it ;)

thx! ill reseach it.

[Shadox75]

Anything wrong with this, I keep getting an error saying "no script found"

 -- Functions
file = io.open("counter.txt", "r")
counter = file:read("*n")
file:close()
selector = { image = Image.createEmpty(145,15), x = 147,y = 77 }
selector.image:clear(blue)
function drawMenu()
screen:clear()
pad = Controls.read()
screen:blit(selector.x,selector.y,selector.image)
screen:print(150,80,"Start Game (Black)",white)
screen:print(150,100,"Start Game (Blue)",white)
if pad:up() and oldpad:up() ~= pad:up() then
selector.y = 77
startcolor = black
local sound = menusound
voice = sound:play()
end

if pad:down() and oldpad:down() ~= pad:down() then
selector.y = 97
startcolor = blue
local sound = menusound
voice = sound:play()
end

if pad:cross() and oldpad:cross() ~= pad:cross() then
gamestate = "game"
counter = counter + 1
file = io.open("counter.txt","w")
file:write(counter)
file:close()
end
end

function playGame()
screen:clear(startcolor)
pad = Controls.read()

screen:print(100,100,"This program has been executed " .. counter .. " times.",white)
screen:print(100,110,"Press Start to exit to Menu",white)

if pad:start() then
gamestate = "menu"
local sound = goodbye
voice = sound:play()
end
end

-- Main Loop
while true do

if gamestate == "menu" then
drawMenu()
end

if gamestate == "game" then
playGame()
end

screen.flip()
oldpad = pad
end

[Grimfate126]

Anything wrong with this, I keep getting an error saying "no script found"

 -- Functions
file = io.open("counter.txt", "r")
counter = file:read("*n")
file:close()
selector = { image = Image.createEmpty(145,15), x = 147,y = 77 }
selector.image:clear(blue)
function drawMenu()
screen:clear()
pad = Controls.read()
screen:blit(selector.x,selector.y,selector.image)
screen:print(150,80,"Start Game (Black)",white)
screen:print(150,100,"Start Game (Blue)",white)
if pad:up() and oldpad:up() ~= pad:up() then
selector.y = 77
startcolor = black
local sound = menusound
voice = sound:play()
end

if pad:down() and oldpad:down() ~= pad:down() then
selector.y = 97
startcolor = blue
local sound = menusound
voice = sound:play()
end

if pad:cross() and oldpad:cross() ~= pad:cross() then
gamestate = "game"
counter = counter + 1
file = io.open("counter.txt","w")
file:write(counter)
file:close()
end
end

function playGame()
screen:clear(startcolor)
pad = Controls.read()

screen:print(100,100,"This program has been executed " .. counter .. " times.",white)
screen:print(100,110,"Press Start to exit to Menu",white)

if pad:start() then
gamestate = "menu"
local sound = goodbye
voice = sound:play()
end
end

-- Main Loop
while true do

if gamestate == "menu" then
drawMenu()
end

if gamestate == "game" then
playGame()
end

screen.flip()
oldpad = pad
end

does it give a line number?? or it just could be that ur using windows luaplayer and u named ur script wonrg.

[Shadox75]

I forgot to include some of the code.

 -- Colors
white = Color.new(255,255,255)
blue = Color.new(0,0,255)
black = Color.new(0,0,0)

-- Variables
oldpad = Control.read()
startcolor = black
gamestate = "menu"
menusound = Sound.load("Sounds/beep.wav",false)
goodbye = Sound.load("Sounds/goodbye.wav",false)

-- Functions
file = io.open("counter.txt", "r")
counter = file:read("*n")
file:close()
selector = { image = Image.createEmpty(145,15), x = 147,y = 77 }
selector.image:clear(blue)
function drawMenu()
screen:clear()
pad = Controls.read()
screen:blit(selector.x,selector.y,selector.image)
screen:print(150,80,"Start Game (Black)",white)
screen:print(150,100,"Start Game (Blue)",white)
if pad:up() and oldpad:up() ~= pad:up() then
selector.y = 77
startcolor = black
local sound = menusound
voice = sound:play()
end

if pad:down() and oldpad:down() ~= pad:down() then
selector.y = 97
startcolor = blue
local sound = menusound
voice = sound:play()
end

if pad:cross() and oldpad:cross() ~= pad:cross() then
gamestate = "game"
counter = counter + 1
file = io.open("counter.txt","w")
file:write(counter)
file:close()
end
end

function playGame()
screen:clear(startcolor)
pad = Controls.read()

screen:print(100,100,"This program has been executed " .. counter .. " times.",white)
screen:print(100,110,"Press Start to exit to Menu",white)

if pad:start() then
gamestate = "menu"
local sound = goodbye
voice = sound:play()
end
end

-- Main Loop
while true do

if gamestate == "menu" then
drawMenu()
end

if gamestate == "game" then
playGame()
end

screen.flip()
oldpad = pad
end

It won't work.

It says

error: index.lua:7: attempt to index global 'Control' (a nil value)
ERROR: No script file found

I am using LUA on my PSP.

[Access_Denied]

At line 7 it's Controls.read() not Conrol.read(). You have to put the "s" in controls.
-= Double Post =-
Does anyone know of a way where if I hold down the UP/DOWN button, it scrolls fast, but if I just tap it, it scrolls one at a time. Like in the PSP's XMB.

[vettefan]

if your using lua player through eloader you may get no script found error.
that kept happening to me when I had to use eloader.

[Shadox75]

I was using 1.50, I got to it work.

[slicer4ever]

@access_denied just try the following:

blue = Color.new(0,0,255)
screen:clear()
player = Image.createNew(5,5) -- i know it's sometin like that
player:clear(blue)

button = "no"
time_held = 0
x = 240
y = 0
oldpad = pad
while true do
pad = controls.read()
if time_held < 20
if pad:left() then
time_held = time_held + 1
endif
if pad:left() and oldpad:left() ~= pad:left() then
x = x - 1
end
end
if oldpad:left() ~= pad:left() then
time_held = 0
end
if time_held > 19 then
if pad:left() then
x = x - 1
end
end
screen:blit(x,y,player)
screen.flip()
screen.waitVblankStart()
oldpad = pad
end

somtin like that should work