Lua Programming Help Thread

[yaustar]

can anyone point me to some code that can rotate an image?

With or without the GU?

[Merick]

hmm...

well, right now my program is only using 2d, I haven't even looked at the 3d GU yet, but if the GU can be combined with my 2d stuff without problems, and if it works better than a 2d function would....

Basically, I'm making a tile map editor and I'd like to be able to rotate the tile images by 1/4, 1/2, and 3/4 turns

[eldiablov]

gu works better than any other way. but i dont know if it will cooperate with your 2d stuff easily

[yaustar]

Doing it without the GU is (very?) slow but still possible.

This will help: http://forums.qj.net/f-psp-developme...lua-98105.html

[Merick]

thanks, I will eventually be looking into the gu, but for now it looks like this will do what I need

[TacticalPenguin]

Round a number:

function roundnum(roundnum_num)
return math.floor(roundnum_num+0.5)
end

Or just use

math.floor(number+0.5)

[sulfer]

hii all,
I want to copy a file, but i don't know how...
It shoud work like when you are in level 5 of my game a photo need to be copied
to the photo map

[Merick]

Sulfer, do you mean like copy a file that's already on your memcard, or do you want to make a screenshot or something?

[pspfreak9]

Hey in netlib you need netget(id)? Becuase i looked at some online games and they dont use netget when reciing from yourgame_room..room_numbe r. They just netrecv() and netvalue, so I took out netget from the example and it didn't work?? Is there a reason for this.

[sulfer]

@Merick, i want copy file's that are already on my memstick, could you help me whit that? thx
(ps don't flame me for my english :o )

[the undead]

Is it possible to disable a button in lua?....like lets say the "home" button. if so how

[Merick]

this will copy a file:

file = io.open("filename.ext","r")
filecopy = file:read("*a")
file:close()

copiedfile = io.open("newfile.ext", "w")
copiedfile:write(filecopy)
copiedfile:close()

[the undead]

wont that just copy whats in a file and paste it in a already created file?

[Merick]

only if "newfile.ext" already exists. If you use the io.open and write commands with a filename for a file that doesn't exist, then it will create a new file with that name to write to

[Access_Denied]

Is it possible to disable a button in lua?....like lets say the "home" button. if so how

No, there is not. If you would like to disable people from using the HOME button, modify the LuaPlayer src to disable the callbacks. Takes about 5 seconds.

[Merick]

Well, I have successfully integrated KleptoOne's image rotate function into my prog. It works fine, except that the rotated images it produces end up a bit distorted. It'll do for now but eventually I'll need to find a better way.

[the undead]

No, there is not. If you would like to disable people from using the HOME button, modify the LuaPlayer src to disable the callbacks. Takes about 5 seconds.

ok, so do i need to install psptoolchain and cgwin or w/e?

[KleptoOne]

Well, I have successfully integrated KleptoOne's image rotate function into my prog. It works fine, except that the rotated images it produces end up a bit distorted. It'll do for now but eventually I'll need to find a better way.

I found out the best way is to use the GU. what you do is draw four triangles with starting points in the center forming a square. Then you texture your image over it and modify the z value to change its size and (depending on how you drew the triangles) modify the roll to rotate. If you want some sample code, let me know.

[eyece]

2 triangles would be easier, or one rectangle.
and using gu over top of the rest of your game is kind of a bad idea, make it all gu rendered or none of it gu rendered.

[GuitarGod1134]

ok, so do i need to install psptoolchain and cgwin or w/e?

Well yah because you would need to recompile it after you disables the callbacks.

[KleptoOne]

2 triangles would be easier, or one rectangle.
and using gu over top of the rest of your game is kind of a bad idea, make it all gu rendered or none of it gu rendered.

I found that 2 triangles rotates the image at the corner rather than the center. Is it just the way I drew the triangles that gives me that glitch? Also how do you draw rectangles in lua?

[eyece]

its how to have positioned the texture, it should be in the center.
(middleOfSquare - (widthOfTexture / 2)) basically

[Joel Van]

Can someone tell me what the exact .WAV audio support is for LUA?

[Merick]

Seeing as I haven't even looked at the GU yet, I'm not even sure how I would convert my current tile drawing routines to use it. On the other hand, If i could use the GU to blit a rotated image to the screen and then use a screen capture function to save it as a regular 2d image in my tile array, then that should be pretty easy to combine with what I already have

[the undead]

Can u open up a prx in lua and change a specific part of the code?

[eldiablov]

right guys another day, another question. Im still not sure if im doing the right thing. Right im using scanf to remember the letters that i enter but here's my problem when scaning for an integer you just do int NAME OF VARIABLE;
what would you enter for a string ?

[sulfer]

this will copy a file:

file = io.open("filename.ext","r")
filecopy = file:read("*a")
file:close()

copiedfile = io.open("newfile.ext", "w")
copiedfile:write(filecopy)
copiedfile:close()

thx for the help, but how can you define wher it's need to be copied?

[Merick]

Just put in the name of the folder where you want it to go:

"./folder name/filename.ext"

[the undead]

y doesnt this work?....it doesnt write to the file, or print it
here is my code

irsignal = nil
System.irdaInit()

while true do
pad = Controls.read()
screen:clear()
if irsignal == nil then
irsignal = System.irdaRead()
end
if irsignal ~= nil then
screen:print(10, 10, irsignal)
end
if pad:cross() then
copiedfile = io.open("remote.txt", "w")
copiedfile:write(irsignal)
copiedfile:close()
end
screen.flip()
end

[Merick]

I don't really know anything about using the irda, but are you sure that you've got the sensor lined up properly with whatever device you're trying to read from?