Lua Programming Help Thread

[Anti-QuickJay]

Ok, I guess i might have to test it out to see if i can notice a difference.

[Grimfate126]

Why would you free than load an image? Im sure you can load an image into another one....

image = Image.load("blah.png")

image = Image.load("blah2.png")

while true do
     screen:blit(0,0,image)
     screen.waitVblankStart()
     screen.flip()
end

Im too lazy to test that out.

that would just overwrite the first definition. not sure if thats what you wanted though.

[SG57]

Gah - you guys are idiots... That snippet was for TP, he said nil frees an image, true, but i said reload, meaning just overwrite it with another image's data as ive done in the snippet. AS for loading from memory, there wont be any noticeable difference, since your still loading an image off the memory stick into RAM, than into an image class if you wish... To be honest, take snakesp that comes with luaplayer, change all image loading routines with a load from memory routine, and see if there is a difference.

[BlackShark]

I got a question!

Im editing TP's browser snippet, and I want to make it so that if you click on a directory with an "index.lua" OR "index.LUA" in it, it runs that file.

this is what i have so far.....

	if pad:cross() and bfold == true and fl[s].directory == true then
	System.currentDirectory("./APPS/"..fl[s].name)
	dofile("index.LUA")
	System.currentDirectory("./../..")
end

first off,

fl=System.listDirectory()
and

fl[s].name = the file/directory that you are curretly on
and

nf=table.getn(fl)

I hope that helps, Thanks in advance

[HeaD_ShOt]

now i got a new question
with this bullet fireing method

bullet = Image.createEmpty(4,4)
bullet:clear(red)

oldpad = Controls.read()
currentBullet = 0
direction = "left"

Player = {}
Player[1] = { x = 180, y = 117 }

BulletInfo = {}
for a = 1,5 do
BulletInfo[a] = { pic = bullet , firing = false, direction = "left", x = Player[1].x + 32,
y = Player[1].y + 16 }
end

function bulletSetup()
if currentBullet < 5 then
currentBullet = currentBullet + 1
else
currentBullet = 1
end

if direction == "left" then
BulletInfo[currentBullet].x = Player[1].x
BulletInfo[currentBullet].y = Player[1].y + 16
end

BulletInfo[currentBullet].direction = direction
BulletInfo[currentBullet].firing = true
end

function bulletFire()
for i = 1,5 do
if BulletInfo[i].firing == true then
if BulletInfo[i].direction == "left" then BulletInfo[i].x = BulletInfo[i].x - 10 end
screen:blit(BulletInfo[i].x,BulletInfo[i].y,BulletInfo[i].pic)
end
if BulletInfo[i].x < 0 or BulletInfo[i].x > 480 or BulletInfo[i].y < 0 or BulletInfo[i].y > 272 then
BulletInfo[i].firing = false
end
end
end

then the collision

function collisionCheck2()
if BulletInfo[i].y == ufo1.y then
ufo1.x = 0
ufo1.y = 120
end
end

it says
error
attempt to index feild '?' (a nil value)
for the bolded line

what is the y coordinant of the bullet???

[Urameshi]

I get a bad blit error on line 123, and I need help fixing it

thanks in advance

dofile("animLib.lua")

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

Background=Image.load("training.png")

spritesheet=Image.load("naruto8ad.png")
spritesheet1=Image.load("naruto8ad1.png")
Punch1=Image.load("punchrt1.png")
Punch2=Image.load("punchrt2.png")
Punch3=Image.load("punchrt3.png")
Sasuke=Image.load("sasukeleft.png")

r1=Image.createEmpty(30,38)
r2=Image.createEmpty(30,38)
r3=Image.createEmpty(30,38)
r4=Image.createEmpty(30,38)
l1=Image.createEmpty(30,38)
l2=Image.createEmpty(30,38)
l3=Image.createEmpty(30,38)
l4=Image.createEmpty(30,38)
l1:blit(0,0,spritesheet1,430,103,30,38)
l2:blit(0,0,spritesheet1,432,155,30,38)
l3:blit(0,0,spritesheet1,399,155,30,38)
l4:blit(0,0,spritesheet1,366,155,30,38)
r1:blit(0,0,spritesheet,52,104,30,38)
r2:blit(0,0,spritesheet,49,155,30,38)
r3:blit(0,0,spritesheet,83,155,30,38)
r4:blit(0,0,spritesheet,116,155,30,38)


r={r1,r2,r3,r4}
l={l1,l2,l3,l4}
rt={rt1,rt2,rt3}

Player={x=0,y=200,w=30,h=38,d=r,s=1,animt=0,img=r1,oldimg=l1,}
Sasuke={x=400,y=200,w=32,h=38,img=Sasuke}

PlayerHeight=38
PlayerWidth=32


function collision(ob1,ob2)
if (ob1.x + ob1.w > ob2.x) and (ob1.x < ob2.x + ob2.w) then
ob1.x=ob1.img
end
end

function anim(ob)
	ob.animt = ob.animt + 1
	if ob.animt > 30 then
		ob.animt = 1
	end
	if ob.animt < 6 then
		ob.img = ob.d[1]
	end
	if ob.animt > 5 then
		ob.img = ob.d[2]
	end
	if ob.animt > 10 then
		ob.img = ob.d[3]
	end
	if ob.animt > 15 then
		ob.img = ob.d[4]
	end
	
end		

function movePlayer()
pad=Controls.read()
if pad:right() then 
		Player.d=r
		anim(Player)
		Player.x=Player.x+Player.s
else
Player.img=Player.d[1]
		end		
	if pad:left() then
		Player.d=l
		anim(Player)
		Player.x=Player.x-Player.s
		end
	if pad:cross() then
		Player.oldimg = Player.img
		if Player.d == r then Player.img=block elseif Player.d == l then 

Player.img = block1 end
		defending=true
		end
		if defending and not pad:cross() then
		defending=false Player.img=Player.oldimg
		end
	if pad:down() then
		Player.oldimg = Player.img
		if Player.d == r then Player.img=crouch elseif Player.d == l then 

Player.img=crouch1 end		
		crouching=true
		end
		if crouching and not pad:down() then
		crouching=false Player.img=Player.oldimg
		end
end


oldpad=Controls.read()
block1=Image.load("block1.png")
block=Image.load("block.png")
crouch=Image.load("crouch.png")
crouch1=Image.load("crouch1.png")
crouching=false
defending=false
punching=false

while true do	

movePlayer()

--check collision for Sasuke
if collision(Player,Sasuke) then
	Sasuke.img=Sasuke.img	
	screen:print(100,100,"It works",white)
end
	
--paste player to screen
screen:blit(0,0,Background,true)
screen:blit(Player.x,Player.y,Player.img)
screen:blit(400,200,Sasuke.img)

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

[TacticalPenguin]

Hey blackshark, add me on MSN or AIM and I can help you with whatever you're trying to do with my filebrowser snippet.

Also, SG, you said REload. But when you UNload an image (making it need REloading) it has been set to nil and dropped from ram. I know that you can change an images value and stuff, your interpretation of reload was just different from mine.

Also [email protected] bullet snippet. You want a real bullet system to use?

Also kinghiei, here's your problem:

You're defining Sasuke = Image.load("sasukeleft.pn g")

And then redefining it as a table with its original value inside:

Sasuke = {blahblah,img = Sasuke}

Either change the name of the imageload or the table. You cant use the image of Sasuke any more since you redefined Sasuke as a table.

E.G. Sasukeimg = Image.load("sasukeleft.pn g")
Sasuke = {blahblah,img = Sasukeimg}

[Urameshi]

I still got the bad blit error

[HeaD_ShOt]

Also [email protected] bullet snippet. You want a real bullet system to use?

yes,
i want a real bullet system

[eyece]

kinghiei, your missing the clip part of the blit function:

screen:blit(0, 0, Background, 0, 0, Background.width(), Background.height(), true)

[SG57]

A 'real' bullet system is game specific.

[TacticalPenguin]

Yea, it usually is, but if the evilmana one will do what he needs so will the one I sent him.

[BlackShark]

Hey blackshark, add me on MSN or AIM and I can help you with whatever you're trying to do with my filebrowser snippet.

I do not have either, sorry.

[eyece]

can i ask everyone what they think of this:
http://www.sendspace.com/file/e44t0q
its a game i just started, just tried to add a walking animation witch didn't work as well as i had hoped so its kind of low on fps and moving looks lame IMO.

[HeaD_ShOt]

i tried using os.exit() to exit to the xmb
but all it does is cause a freeze...

[SG57]

eyece - Check out my game, Be Thou' for the People - it is a FMA Beat em up and has all animations in, except alchemic animations.

http://JordanSg57.googlepages.com/Be...rThePeople.rar

WAlking animation, kicking animation, jumping animation, and enemies.

Maybe take a look? Or if you really want tohelp me, do the enemies AI ;) Ive done everything except that, and thats the only thing stopping me from completeing hte game.

[emericaska8r]

can i ask everyone what they think of this:
http://www.sendspace.com/file/e44t0q
its a game i just started, just tried to add a walking animation witch didn't work as well as i had hoped so its kind of low on fps and moving looks lame IMO.

its pretty cool. i'm not sure what moving the legs actually does, but I think it's a good idea to actually use physics concepts in a game like you do.

good luck with it.

[myschoo]

i tried using os.exit() to exit to the xmb
but all it does is cause a freeze...

use System.Quit()
but u must have cools Luaplayer mod

-= Double Post =-

can anyone explain why this:

print("about " .. System.getFreeMemory() / 1024 / 1024 .. " megabytes free memory available")

doesnt work....

but when i use this:

System.getFreeMemory() / 1024 / 1024 * 16,37152777777777778

then it works ok... o_O

[TacticalPenguin]

Try something like:

memfree = System.getFreeMemory()/1024/1024
print("About "..math.floor(memfree+0.5 ).." megabytes of free memory")

The math.floor(memfree+0.5) part rounds it to the nearest number. It's about, not exactly.

[emericaska8r]

did that person ever change their name so you could be penguin again?

[HeaD_ShOt]

i have a question
is there any way to have mutiple locations of x
like enemy.x = enemy.x and everything between enemy.x + 15
?

[EminentJonFrost]

i have a question
is there any way to have mutiple locations of x
like enemy.x = enemy.x and everything between enemy.x + 15
?

um..no.
but you could use tables instead.

enemy[1].x = enemy[2].x
or
enemy.1.x = enemy.2.x (tables inside tables lol)

[HeaD_ShOt]

so u cant do
like
enemy.x through enemy.x + 15
in lua

[pspfreak9]

Hey guys in my code this wont work:

netget("p1")


while true do
	netrecv()
	buffer = netvalue("p1")
		if buffer == "0" then 
			screen:print(0,0,buffer,red)
screen.waitVblankStart(); 
screen.flip()
			
		end
end

But when I modded the netlib example and did this it worked in the example:

netget("p1")


while true do
	netrecv()
	buffer = netvalue("p1")
		if buffer == "0" then 
			print(buffer)
			break
		end

The first one is from my game dosent work thx for all help.

[andyauff]

Does anyone know of a way to do something if a certain button is being pressed and it hasn't been pressed for a certain amount of time? For example, I want to use the l trigger to go back one "page" in my new app, Todo Espanol. However, I don't want it to go back so quickly that it just flies through. I want it to go back just one page, and be able to press it again to go back again (no oldpad stuff). Thanks for any help.

[TheBressman]

Tryin my hand at making a simple program in LUA.
Need to know two things:
1. Is it possible to copy a file and then paste it in another folder using LUA ?
2. I heard speak of LUA being able to write to flash1 (I'm not interested in flash0, too risky). Is this possible ? And if so, how ? :)

[BlackShark]

you MIGHT be able to write to flash1 (not flash0) MIGHT...not too sure...but you CAN read flash1 and flash0 easily.
as for copying and pasteing to a file, I don't know, good question though.

[TacticalPenguin]

To copy and paste a file try somethin like:

copyingfile = io.open("fileyouwannacopy .ext","r")
copyingtofile = io.open("nameoffileuwanna copyitto.ext","w")
for line in copyingfile:lines() do
copyingtofile:write(line. ."\n")
end

The copyingtofile doesnt have to exist, itll create it.

[TheBressman]

I get an error with that code:
error: modified.lua:85: attempt to index global 'copyingfile' (a nil value)

function backup()
System.currentDirectory(" c:\directory")
copyingfile = io.open("file.ext","r")
for line in copyingfile:lines() do
System.currentDirectory(" c:\directory2")
copyingtofile = io.open("file.ext","w")
copyingtofile:write(line. ."\n")
end
end

Any insights TP ?

[Anti-QuickJay]

To copy and paste wouldn't you copy the file then make a new file and paste?