Lua Programming Help Thread

[mark.sparky]

well have you put a number in the highscore text

[Nutterbutter]

these are the variables at the start. theres nothing wrong cos it can display them in the game:

highscore = io.open("hiscore.txt","r")
theHighScore = highscore:read() --this is where it reads the file, it doesnt read it as a number
score = 0

Im not great with lua but you opened the file with an "r" tag? Wont that mean you can only read?

[Grimfate126]

these are the variables at the start. theres nothing wrong cos it can display them in the game:

highscore = io.open("hiscore.txt","r")
theHighScore = highscore:read() --this is where it reads the file, it doesnt read it as a number
score = 0

-= Double Post =-


yer, it cant read the info in the document as a number, help!

NVM, read mark.sarpkys post.

[JaSo PsP]

here:

levelTimer = Timer.new(100000)
levelTimer:start()
red = Color.new(255,0,0)
background = Image.load("cloud.png")
smiley = Image.load("smile.png")
sad = Image.load("sad.png")
math.randomseed(os.time())
rx = math.random(0,442)
ry = math.random(0,234)
highscore = io.open("hiscore.txt","r")
whighscore = io.open("hiscore.txt","w")
theHighScore = highscore:read()
boost = 2000
score = 0
x = 0
y = 5
TotalTimeLimit = 130

-= Double Post =-

well have you put a number in the highscore text

yes i have, it was 0 but i changed it to 10 and thats all thats there.

cmon help me!!!

[yaustar]

The problem here is that when you read from a file, its reading it in as a string, not a number. Therefore you cannot compare a number with the string.

[JaSo PsP]

The problem here is that when you read from a file, its reading it in as a string, not a number. Therefore you cannot compare a number with the string.

so how can i save a high score?

[yaustar]

At the moment I am looking for a string to number/integer function in Lua (I really don't fancy writing one myself) but can't find any.

[JaSo PsP]

At the moment I am looking for a string to number/integer function in Lua (I really don't fancy writing one myself) but can't find any.

k, im gonna fishish off the game and post it without the hiscore thing.
-= Double Post =-
what do i write to make the whole thing restart? well?

[yaustar]

Note that this code is for a standalone project only. You MUST press start to exit otherwise the file doesn't not get saved:

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

highscore = io.open("hiscore.txt","r")
theHighScore = highscore:read("*number")
highscore:close()

currentScore = 0

while true do

    PspPadState = Controls.read();

    if PspPadState:start() then
	    break;
	end
	
	if PspPadState:circle() then
	    currentScore = currentScore + 1
	end

	screen:clear(WHITE)
	screen:print(1,1, "High Score    " .. theHighScore)
	screen:print(1,9, "Current Score " .. currentScore)
	
	screen.waitVblankStart();
	screen.flip();
end

if currentScore > theHighScore then
    highscore = io.open("hiscore.txt","w")
    highscore:write(currentScore)
    highscore:close()
end

[JaSo PsP]

Note that this code is for a standalone project only. You MUST press start to exit otherwise the file doesn't not get saved:

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

highscore = io.open("hiscore.txt","r")
theHighScore = highscore:read("*number")
highscore:close()

currentScore = 0

while true do

    PspPadState = Controls.read();

    if PspPadState:start() then
	    break;
	end
	
	if PspPadState:circle() then
	    currentScore = currentScore + 1
	end

	screen:clear(WHITE)
	screen:print(1,1, "High Score    " .. theHighScore)
	screen:print(1,9, "Current Score " .. currentScore)
	
	screen.waitVblankStart();
	screen.flip();
end

if currentScore > theHighScore then
    highscore = io.open("hiscore.txt","w")
    highscore:write(currentScore)
    highscore:close()
end

it works but the mem stik light keeps flashing, when i exit the app after bout 10 seconds of flashing it has saved the score?
-= Double Post =-
sorted it out with the flashing..

[yaustar]

Nothing I can do about that. Looks like LuaPlayer syncs to the memory card when the file is closed whcih ensures that the data is written to card and flushes the buffer. I wouldn't have thought it be 10 secs though.

[JaSo PsP]

i now just need to know, when the game ends, and it says game over, how to i make triangle make the game restart? what tells the game to restart?
-= Double Post =-

Nothing I can do about that. Looks like LuaPlayer syncs to the memory card when the file is closed whcih ensures that the data is written to card and flushes the buffer. I wouldn't have thought it be 10 secs though.

nah thats sorted.
-= Double Post =-
finished game...

[JoeDaStudd]

restart button
put this in/near your game over function/loop

if pad:triangle() then
dofile(".index.lua")
end

[Gonrai]

I keep getting this weird error:
Heres my code:

-- Alien Cross Hair Menu Screen

-- Create Colors
white = Color.new(255,255,255)
red = Color.new(255,69,0, 195)


-- Load Background
Background_Menu = Image.load("./Images/back_menu.png")

-- Load Arrow Image
arrow = Image.load("./Images/arrow_down.png")


-- The Loop
while true do
screen:blit(0,0,Backgroun d_Menu)
screen:blit(208,193,arrow )
oldpad = Controls.read()
pad = Controls.read()

-- Prints our 4 menu options
screenrint(208,96,"Start Game",white)
screenrint(128,144,"Credits",wh ite)
screenrint(208,192,"How To Play",white)
screenrint(288,144,"Exit To XMB",white)
-- These make it so when the variable "current" changes
-- so does the current menu selection
if current == 1 then
screenrint(208,96,"Start Game",red)
screen:blit(208,97,arrow)
end
if current == 2 then
screenrint(128,144,"Credits",re d)
screen:blit(128,145,arrow )
end
if current == 3 then
screenrint(208,192,"How To Play",red)
end
if current == 4 then
screenrint(288,144,"Exit To XMB",red)
screen:blit(288,145,arrow )
end

if pad:up then
current = 1
end

if pad:left then
current = 2
end

if pad:down then
current = 3
end

if pad:right then
current = 4
end

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

Heres my error:
Error: menu.lua:45: function arguments expected near /then/
??????

[Access_Denied]

if pad:down() then
if pad:left() then
if pad:right() then
if pad:left() then

You have to have function arguments after buttons.
-= Double Post =-
http://evilmana.com/tutorials/codebase/simple_menu.php

I would use that to make a menu. It's much better.

[Gonrai]

Hey guys, sorry for that long code, I figured out the problem, I just forgot to put the () infront of my pads
LOL, aha.
EDIT:
aww, someone beat me to it.

Hold on, I have another question.
Whats the correct coding for getting back to the XMB?

[Branin]

there is no code to get back to XMB from luaplayer. but you can the eboot from the modded luaplayer and use the System.Quit() command as LMelior stated before.. PM me if you need help with that.

[JaSo PsP]

where does it actually define the variable 'current'?

[jamz1825]

ok...
you know how when u screen:blit it makes the image show up?
well is there a way you can do the opposite?

like i want it so when i press r my first image dissapeers and a new one comes up.

i have thing sort of working but when i press r the new image shows up just on top of the old one. and they both continue to like they are spossed too.
please tell me what i have to do to make the original dissapear when r is pressed. here is my code..


Player = { }
Player[1] = { x = 200, y = 197 }

while true do
pad = Controls.read()
screen:clear()
screen:blit(Player[1].x,Player[1].y,player)

if pad:l() and Player[1].x > 0 then
Player[1].x = Player[1].x - 2
end

if pad:r() and Player[1].x < screenwidth then
Player[1].x = Player[1].x + 2
screen:blit(Player[1].x,Player[1].y,player2)
end

[Nutterbutter]

@ Jamz, when you blit an image it isnt actually written to the screen. Its written to the buffer. When flip.Screen is executed the buffer is drawn to the screen. So you put what you want blitted in an if loop. I dont know lua, but ill try.

if playerblit = 1 then

 //* Blit code for player.

end

//* Then set up a pad input so that if R is pressed playerblit equals 0

[jamz1825]

ok thnx ill try that

[xsorifc28]

how do you display text on a coordinate and keep it their while on another coordinate, display text and keep changing it? get what im saying?

[jamz1825]

ok nutterbuter i did what u said but now when i press "r" the value of player is permannently changed to zero. is there a way to temporarily change the value so it is zero only when r is pressed


EDIT: nvm i fixed it

[Nutterbutter]

ok nutterbuter i did what u said but now when i press "r" the value of player is permannently changed to zero. is there a way to temporarily change the value so it is zero only when r is pressed


EDIT: nvm i fixed it

Yay, i actually used my skills for good!

[Dr.Gringo]

When you screenrint text is there a way to automatically skip a certain amount of pixels down once the text has filled the screen. If you need any more details please post... Any help would be really appreciated. Im looking for a way to make a paragraph without alot of hassle.

[Access_Denied]

There is no way to automatically go to the next line. The best way to do it is as follows.
1. Open up Photoshop or the Gimp
2. Open up you picture
3. Write the text on the picture
4. Save it as a .PNG file

[yaustar]

Unless string.gfind is implemented in the latest LuaPlayer, this is the best I can do (Note the chopping of text at the end of the line). Probably really slow as well. Press left and right to narrow widen the text width.

WHITE = Color.new(255, 255, 255);
BLACK = Color.new(0, 0, 0);

-- Just wrapping text round a screen. Problem. Chops words
Str_BigStringOfTextFromFile = "I can't tell you all how great it is to finally talk about what we've really been building in the XNA team. At GDC this year we showed off managed code running on an Xbox 360. We positioned it as a tool to help the professional industry, which it is. I expect it to be an excellent environment for casual games of all types and it will make inroads into FPS and other big games over time."
Int_TextWidth = 40;

Int_StartLineY = 1;
Int_LineHeight = 9;

while true do

    PspPadState = Controls.read();

    if PspPadState:start() then
	    break;
	end
	
	if PspPadState:left() and Int_TextWidth > 1 then
	    Int_TextWidth = Int_TextWidth - 1;
	end
	
	if PspPadState:right() and Int_TextWidth < 60 then
	    Int_TextWidth = Int_TextWidth + 1;
	end
	
	screen:clear(WHITE);

	-- Get the current length of the screen
	local Int_LengthOfString = string.len(Str_BigStringOfTextFromFile);

	-- Get the number of lines in the string
	local Int_NumberOfLines = math.abs(Int_LengthOfString / Int_TextWidth);

	Int_CurrentLine = 0;
	for i=0,Int_NumberOfLines do
	    local Str_Line = string.sub(Str_BigStringOfTextFromFile, (i*Int_TextWidth)+1, ( (i+1)*Int_TextWidth) );
	    screen:print(1, (Int_StartLineY+(Int_LineHeight*Int_CurrentLine)), Str_Line);
	    Int_CurrentLine = Int_CurrentLine + 1;
	end

	screen.waitVblankStart();
	screen.flip();
end

[LMelior]

When you screenrint text is there a way to automatically skip a certain amount of pixels down once the text has filled the screen. If you need any more details please post... Any help would be really appreciated. Im looking for a way to make a paragraph without alot of hassle.

I wrote a function to do this a while ago, it might help you. There are tons of comments, so read the ones at the top (just below the function definition) and see if it fits your application. It looks pretty cluttered with all of the in-code comments, but they explain what the code is doing so it should be easy to modify.

function printMLtext(x, y, str, color, maxlen, vspacing, maxlines)

   -- DESCRIPTION
   -- Divides strings to allow for easy multiline printing.  Designed to be similar in syntax
   -- to the screen:print command, and actually can be used as a replacement for the
   -- command entirely.  Note that this has been tested for the default font and default
   -- text size only, although it should work with any mono-spaced font and text size. 
   -- LMelior 7/18/2006
   --
   -- INPUTS
   -- "x" and "y" - the horizontal and vertical pixel location of the first character.
   -- "str" - the input string
   -- "color" - the color of the text
   -- "maxlen" (optional, but you probably want to set this) - maximum number of
   -- -- characters you want to allow on one line. 
   -- -- -- The default value is 60 (it is the maximum number of characters that will fit on the
   -- -- -- -- PSP screen when using the PSP's default font).
   -- "vspacing" (optional) - vertical spacing, in pixels,  between consecutive lines of text
   -- -- The default value is 15 pixels.
   -- "maxlines" (optional) - allows you to define the maximum number of lines of text that
   -- -- you want to display, and it will wait for player input to continue to the next line.  If
   -- -- -- the input string exceeds these parameters, it will only print the first screen, but it
   -- -- -- -- will return the remainder of the string, so you can easily run it through again
   -- -- -- -- -- (see Example 2).
   -- -- -- -- -- -- The default value is 18 lines, because along with the other defaults, this
   -- -- -- -- -- -- -- will fill up the entire PSP screen with text.   
   -- Note: if you want to define "vspacing" or "maxlines," you must define the
   -- -- parameter(s) before it!
   --
   -- EXAMPLES
   -- Example 1:
   -- -- stra="This string is too long to fit on one line if the "
   -- -- strb="maximum length of the line is 30 characters."
   -- -- printMLtext(230, 10, stra .. strb, Color.new(255,255,255), 30)
   --
   -- Example 2:
   -- str=(very long string)
   -- while true do
   --   screen:clear()
   --   pad=Controls.read()
   --   nextpage=printMLtext(230, 10, str, Color.new(255,255,255), 30, 15, 10)
   --   if pad:cross() and nextpage~=nil then
   --      screen.waitVblankStart(8)
   --       str=nextpage
   --   end
   --   screen.waitVblankStart()
   --   screen.flip()
   -- end

   -- Check for optional input
   if maxlen==nil then
      maxlen=60
   end
   if vspacing==nil then
      vspacing=15
   end
   if maxlines==nil then
      maxlines=18
   end
   
   -- Initialize remainder (will be overwritten if remainder exists)
   local remainder=nil
   
   if string.len(str)<=maxlen then   -- you didn't need to use this!
      screen:print(x,y,str,color)
   else
      local laststr=str   -- initialize variable to hold reduced string
      local strk=0      -- loop counter
      local substr={}      -- initialize substring table
      
      while string.len(laststr)>maxlen do
         strk=strk+1
         
         -- Chop off string at the max length plus one and reverse it (if there's a space at maxlen+1 it's OK!)
         -- -- This doesn't work on Luaplayer 0.14 for Windows, but it probably works in Luaplayer 0.20:
         -- local revstr=string.reverse(string.sub(laststr,1,maxlen))
         
         -- -- This works on Luaplayer 0.14 for windows:
         local tmp=string.sub(laststr,1,maxlen+1) -- chops off string at maxlen+1
         local revstr=""   -- initialize revstr and then build it
         
         for k=1,string.len(tmp) do
            revstr=revstr .. string.sub(tmp,-k,-k)
         end
         
         tmp=maxlen+1-string.find(revstr," ") -- find the index of last space
         
         -- use index to define the substring
         substr[strk]=string.sub(laststr,1,tmp)
         
         -- chop off the first substring to get ready for next loop
         laststr=string.sub(laststr,tmp+2)
      end
      
      -- add the last part of the string to the table (loop terminates before this step)
      strk=strk+1
      substr[strk]=laststr

      -- check of number of lines will fit on the screen in one printing (remainder = nil)
      if strk<=maxlines then
      
         for k=1,strk do
            screen:print(x,y+(k-1)*vspacing,substr[k],color)
         end
         
      else   -- print first screen and then build up remainder string from the unused substrings
      
         for k=1,maxlines do
            screen:print(x,y+(k-1)*vspacing,substr[k],color)
         end
         
         remainder=substr[maxlines+1]
         
         for k=2,strk-maxlines do
            remainder=remainder .. " " .. substr[maxlines+k]
         end
         
      end

   return remainder

   end
end

[Dr.Gringo]

Thanks guys your help is really appreciated! Sorry to ask such a common question but how do i make the text bigger like 12pts to 16pts...

--Thanks

[TheEmulatorGuy]

Thanks guys your help is really appreciated! Sorry to ask such a common question but how do i make the text bigger like 12pts to 16pts...

--Thanks

You can't do that with the in-built font, but if you use your own font you must specify the size.