Lua Programming Help Thread

Allright, i need a code to a kind of clock. Look at my game, its kind of a refleks test. I need it to start when the RanNumer executes and i need it to stop after.

Script:

Zitat:

---

--Colours hehe.

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

--Ok loading.

--Err, no loading, lol.

--So images then.

buttonbg = Image.load("button.png")

buttonbg2 = Image.load("button2.png")

--Timer for refleks.

gametimer=Timer.new()
time=60
gametimer:start()

--ok game now.

while true do

pad = Controls.read()

screen:blit(0, 0, buttonbg, false)
screen.flip

RanNumber = math.random(120,360)
gamestime=gametimer:time( )
screen:clear(black)
screen:blit(0, 0, buttonbg2, false)

if gamestime>1000 then time=time - 1 gametimer:reset(0) gametimer:start()
end

if pad:cross then
gametimer:stop()
end

if pad:start then
break
end

end

---

NOTE: This is ONLY a part of the game. Thats why there is no colours or menu's.

How can i make my player move forward when im holding a button and then move in a circular angle when the directionals are pressed ?

Hehe, we both have very good questions, we both need very good answers.

Zitat:

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Zitat von SG57

Anyways, im still thinking up methods of fading, but i cant seem to set an image to transparent completely, ratheri can only set an image to a completely black color and a transprency %. Know of any LUA app that fades from one image to another?

---

SG57: http://forums.evilmana.com/index.php?topic=157.0
-= Double Post =-

Zitat:

---

Zitat von eldiablov

How can i make my player move forward when im holding a button and then move in a circular angle when the directionals are pressed ?

---

Code:

---

local COLOUR_WHITE = Color.new( 255, 255, 255 );

local imgPlayer = Image.createEmpty( 32, 32 );
imgPlayer:clear( COLOUR_WHITE );

local bQuitGame = false;
local bFirstUpdate = true;

local iPlayerX = 0;
local iPlayerY = 0;

local fPlayerDirX = 0;
local fPlayerDirY = 0;

local iPlayerAngle = 0;

local PLAYER_SPEED = 2;
local FULL_CIRCLE_ANGLE = 360;
local CROSS_HAIR_ROTATION_SPEED = 2;
local DEGREE_TO_RADIAN_CONVERSION = 0.0174532925;

function CalculatePlayerDir( iAngle )
        fPlayerDirX = math.sin( iAngle * DEGREE_TO_RADIAN_CONVERSION );
        fPlayerDirY = -math.cos( iAngle * DEGREE_TO_RADIAN_CONVERSION );
end

while not bQuitGame do
       
        if bFirstUpdate then
                bFirstUpdate = true;
                CalculatePlayerDir( iPlayerAngle );
        end
       
        padCurrentState = Controls.read();
       
        if padCurrentState:start() then
                bQuitGame = true;
        end
       
        if padCurrentState:up() then
                iPlayerX = iPlayerX + math.ceil( fPlayerDirX * PLAYER_SPEED );
                iPlayerY = iPlayerY + math.ceil( fPlayerDirY * PLAYER_SPEED );
        end
       
        if padCurrentState:down() then
                iPlayerX = iPlayerX - math.floor( fPlayerDirX * PLAYER_SPEED );
                iPlayerY = iPlayerY - math.floor( fPlayerDirY * PLAYER_SPEED );
        end
       
        if padCurrentState:left() then
                iPlayerAngle = iPlayerAngle - CROSS_HAIR_ROTATION_SPEED;
                CalculatePlayerDir( iPlayerAngle );
        end
       
        if padCurrentState:right() then
                iPlayerAngle = iPlayerAngle + CROSS_HAIR_ROTATION_SPEED;
                CalculatePlayerDir( iPlayerAngle );
        end
       
        screen:clear();
       
        screen:blit( iPlayerX, iPlayerY, imgPlayer );
        screen.flip ();
       
        screen.waitVblankStart();       
end

---

-= Double Post =-

Zitat:

---

Zitat von gameo

Allright, i need a code to a kind of clock. Look at my game, its kind of a refleks test. I need it to start when the RanNumer executes and i need it to stop after.

---

gameo: What does RanNumber represent? How does it tie in with the timer? What do you need to start? What do you need to finish? When does what stop?

Scrool a little bit up, i posted my code.

SG67 gave me the function RanNumber = math.random

Hey wait a minute... i think i know whats wrong!

I know you posted your code but it tells me nothing about what is RanNumber is used for.

Zitat:

---

I need it to start when the RanNumer executes and i need it to stop after.

---

What is 'it'? Need it to stop after what?

Wait, here is something modified:

Zitat:

---

--Colours hehe.

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

--Ok loading.

--Err, no loading, lol.

--So images then.

buttonbg = Image.load("button.png")

buttonbg2 = Image.load("button2.png")

--Timer for refleks.

gametimer=Timer.new()
time=60
gametimer:start()

RanNumber = math.random(120,360)

--ok game now.

while true do

pad = Controls.read()

screen:blit(0, 0, buttonbg, false)
screen.flip

gamestime = gametimer:time(RanNumber)
screen:clear(black)
screen:blit(0, 0, buttonbg2, false)

if gamestime>1000 then time=time - 1 gametimer:reset(0) gametimer:start()
end

if pad:cross then
gametimer:stop()
end

if pad:start then
break
end

end

---

Its basically the wholel timer i need, that gametimer:time() thing i got from evilmana.

gamestime = gametimer:time(RanNumber)

The function time() doesn't take any parameters.
http://wiki.ps2dev.org/psp:lua_playe...lisecond_timer

No-one will be able to answer your question until you start explictly saying what you need to know.

Zitat:

---

Zitat von head_54us

I know you posted your code but it tells me nothing about what is RanNumber is used for.


What is 'it'? Need it to stop after what?

---

Thanks so much. I didnt know it was on evilmana. I would have never been able to do that on my own. Thanks man :D It would be nice though if you could ind something similar to this http://www.lapoo.nl/batandmouse/

Zitat:

---

Zitat von eldiablov

Thanks so much. I didnt know it was on evilmana. I would have never been able to do that on my own. Thanks man :D It would be nice though if you could ind something similar to this http://www.lapoo.nl/batandmouse/

---

It isn't, the evilmana link was for SG57. The code above is 100% my own.

The game you linked to would mean adding basic physics in such as acceleration, momentum and friction (or at least fake it).

Sorry about that. How easy is it to introduce acceleration ?

fairly easy if you use a timer

Ok then i'll go look around.

Allright, what i basically need is, a random timer to execute a function, as in this case, change the image to a button that is pressed.

I'm working on a refleks game, so i also need the random timer to execute another timer, but which is a timer that counts seconds, for how long you are to react.

Here is my code. You'll see where i need the functions. (I made that clear.)

Zitat:

---

--Colours hehe.

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

--Ok loading.

--Err, no loading, lol.

--So images then.

buttonbg = Image.load("button.png")

buttonbg2 = Image.load("button2.png")

--Timer for refleks.

(INSERT CODE HERE)

--ok game now.

while true do

pad = Controls.read()

screen:blit(0, 0, buttonbg, false)
screen.flip

( I H )
( N C E )
( S O D E R )
( E E )
( RT )

if pad:cross then
gametimer:stop()
end

if pad:start then
break
end

end

---

Help is highly appresiated.

change the image to a button that is pressed.

--create a variable to store which button
cb = buttonbg

Make X switch between them:

if pad:cross() and not oldpad:cross() and cb == buttonbg then cb = buttonbg2
elseif pad:cross() and not oldpad:cross() and cb == buttonbg2 then cb = buttonbg
end

Now please be more detailed on what exactly you need the timer to do EXACTLY.

I need 2 Timers.

Listed very clearly what i want them to do:

1: This timer executes the action to change the background after a random time. For example if you could: screen.waitVblankStart(75-250)

2: This will be executed by the other timer, when timer1 has started, this start counting how long you are to react. like 0,46s.

And then:

if pad:cross() then
(something like timer2 stop)
end

Zitat:

---

Zitat von gameo

I need 2 Timers.

Listed very clearly what i want them to do:

1: This timer executes the action to change the background after a random time. For example if you could: screen.waitVblankStart(75-250)

2: This will be executed by the other timer, when timer1 has started, this start counting how long you are to react. like 0,46s.

And then:

if pad:cross() then
(something like timer2 stop)
end

---

ok, for the first timer, you could do:

Code:

---

timer1:start(0)
random = math.random(75, 250)
--and then in your loop
if timer1:time() > random then
random = math.random(75, 250)
backgrounddisplay = background[current + 1]
timer:reset(0)
timer:start()
end

---

then for your second timer, do like:

Code:

---

reactiontimer:start(0)
while true do--for 'X' lets say
pad = Controls.read()
if pad:cross() then
reactiontimer:stop()
screen:print(5, 5, reactiontimer:time())
end
end

---

hope all that helps or makes sense

I'm curious, how do you find out the FPS of your game/app?

1 divided by the time it takes to process one frame.

how would i code that? i'm not familiar with timers yet.

is it possible to write japanese text with lua?

Why dont you try, Do a screen print but replace it with jap text...

Zitat:

---

Zitat von EminentJonFrost

how would i code that? i'm not familiar with timers yet.

---

Same here. Anyone care to give an example of acceleration ?

Is there a way to crash the PSP or shut it down with lua?
If yes, can someone post ?

I need help with animation and pausing,

i need it so when my charactors state is == "dead"
i need it to display the death animation ONCE then restart or dofile ("FFF.lua")

i am using grimface's animLib 3.5 (awsome btw :D) if you need that peace of code i can put it up if you need it.

Zitat:

---

Zitat von BlackShark

I need help with animation and pausing,

i need it so when my charactors state is == "dead"
i need it to display the death animation ONCE then restart or dofile ("FFF.lua")

i am using grimface's animLib 3.5 (awsome btw :D) if you need that peace of code i can put it up if you need it.

---

post the code your trying. you will have to use the advanced blit.


lol @ grimface

Zitat:

---

Zitat von kimd41

Is there a way to crash the PSP or shut it down with lua?
If yes, can someone post ?

---

use the function:

os.exit()
end

i cant figure out how to get this menu to work:(

Zitat:

---

Zitat von 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()

screen:print(10,10,"Quick Japanese",white)
screen:print(10,20,"by Cheese the Psp, from the QJ forums",white)
screen:print(192,95,"Cate gories",white)
screen:print(192,105,"Alp habet",white)
screen:print(192,115,"Use full Phrases",white)
screen:print(192,125,"Dic tionary",white)

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

if pad:up() then
current = current - 1
end
if pad:down() then
current = current + 1
end
if current == 4 then
current = 1
end
if current == 0 then
current = 3
end

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

if current == 1 and pad:cross() then
dofile("alphabet.lua")
end
if current == 2 and pad:cross() then
dofile("usefullphrases.lu a")
end
if current == 3 and pad:cross() then
dofile("dictionary.lua")
end

---

i'll assume you mean buttons dont work...
also, the code works more efficiently like this:

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,"Cate gories",white)
screenrint(192,105,"Alp habet",white)
screenrint(192,115,"Use full Phrases",white)
screenrint(192,125,"Dic tionary",white)

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

if pad:up() then
current = current - 1
if current == 0 then
current = 3
end
end

if pad:down() then
current = current + 1
if current == 4 then
current = 1
end
end

--move these into the 'while true do' loop, now they'll work
--i also shortened it, though it works the same.
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

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

---

-= Double Post =-

Zitat:

---

Zitat von eldiablov

Same here. Anyone care to give an example of acceleration ?

---

i went to the psDevwiki and looked it up until it made sense.

Code:

---

Timer Timer.new([startTime])
--basically this:
variable_name = Timer.new() -- you've made a timer object.

time = variable_name:start() -- the 'variable_name' timer is started, and its value is kept as 'time'.

what_time_is_it = variable_name:time() -- tells you how much time passed, and that time is kept as 'what_time_is_it'.

time = variable_name:stop() -- stops variable timer.

time = variable_name:reset() -- resets 'time' to zero and stays there until you say so.

---

i tend to ask questions before actually doing research. it took about five minutes to figure it out. (those minutes passed by like hours though, it took alot of concentration, my head hurt afterward. lol)

hey is their a way to do a search in lua?

Like type in a word, then it searches folders for text with a name like the one you typed then print the text file?

Wow... you are asking alot... Try reading up on LUA i/o and learn how to do a recursive search and you should know what todo from there...

Is there a special way to make a variable a negative number or do I just do

variable = -90

?
-= Double Post =-

Spoiler for Snow Simultor:

Code:

---

-- Snow Simulator By GuitarGod1134
-- just simulates a snow weather condition
--color
white = Color.new(255,255,255)
--pics
snow = Image.create(10,10)
snow:clear(white)
background = Image.load("background.png")
--x = width y = hieght
snowxy = {}
snowxy[1] = { x = 30, y = -300}
snowxy[2] = { x = 200, y = -300}
snowxy[3] = { x = 110, y = -300}
snowxy[4] = { x = 97, y = -300}
snowxy[5] = { x = 400, y = -300}
snowxy[6] = { x = 300, y = -390}
snowxy[7] = { x = 250, y = -300}
--is the snow falling
falling = true
--main loop
while true do
screen:clear()
--blit the background
screen:blit(0,0,background)
--blit the snow
snowy = true
if snowy == true then
screen:blit(snowxy[1].x, snowxy[1].y, snow)
end
if snowy == true then
screen:blit(snowxy[2].x, snowxy[2].y, snow)
end
if snowy == true then
screen:blit(snowxy[3].x, snowxy[3].y, snow)
end
if snowy == true then
screen:blit(snowxy[4].x, snowxy[4].y, snow)
end
if snowy == true then
screen:blit(snowxy[5].x, snowxy[5].y, snow)
end
if snowy == true then
screen:blit(snowxy[6].x, snowxy[6].y, snow)
end
if snowy == true then
screen:blit(snowxy[7].x, snowxy[7].y, snow)
end
--make the snow fall
if falling == true then
snowxy[1].y = snowxy[1].y + 2
end
if falling == true then
snowxy[2].y = snowxy[2].y + 2
end
if falling == true then
snowxy[3].y = snowxy[3].y + 2
end
if falling == true then
snowxy[4].y = snowxy[4].y + 2
end
if falling == true then
snowxy[5].y = snowxy[5].y + 2
end
if falling == true then
snowxy[6].y = snowxy[6].y + 2
end
if falling == true then
snowxy[7].y = snowxy[7].y + 2
end
--now we reset them back to true so they can
--fall down again
if snowxy[6].y == 272 then
falling = false
end
--all the snow flakes
--are reset back
--to thier original
--y coordinates
if falling == false then
backup = true
snowxy[1].y = -300
snowxy[2].y = -300
snowxy[3].y = -300
snowxy[4].y = -300
snowxy[5].y = -300
snowxy[6].y = -390
snowxy[7].y = -300
end
--once they reach the bottom
--falling is declared true again
--so that it makes the affect
--that the snow is always falling
if backup == true then
falling = true
end
screen.waitVblankStart()
screen.flip
end

---

Ok when I try to run this I get this really annoying error that for some reason is common in a lot of games I try to make. The error is

error:script.lua:98: '=' expected near 'end'

and Im using windows lua player to test my games if that makes a difference.

And I know there might be some sloppy code in there or something I wrote it in 10 minutes with breakfast in my mind.

Allright, something is properbly wrong still, but here it is:

Zitat:

---

--Colours hehe.

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

--Ok loading.

--Err, no loading, lol.

--So images then.

buttonbg = Image.load("button.png")

buttonbg2 = Image.load("button2.png")

--Timer for refleks.

timer1:start(0)
random = math.random(75, 250)

--ok game now.

while true do

pad = Controls.read()

screen:blit(0, 0, buttonbg, false)
screen.flip


if pad:start then
break
end

if timer1:time() > random then
random = math.random(75, 250)
backgrounddisplay = background[current + 1] -- I dont understand this one.
timer:reset(0)
timer:start()
end

reactiontimer:start(0)

while true do--for 'X' lets say

pad = Controls.read()

if pad:cross() then
reactiontimer:stop()
screen:print(5, 5, reactiontimer:time())
end
end

---

Just for fun i included the button images. I know, very ugly ones...

Zitat:

---

Zitat von SG57

Wow... you are asking alot... Try reading up on LUA i/o and learn how to do a recursive search and you should know what todo from there...

---

ok, ill do that. Thanx

Zitat:

---

Zitat von GuitarGod1134

Is there a special way to make a variable a negative number or do I just do

variable = -90

?
-= Double Post =-

Spoiler for Snow Simultor:

Code:

---

-- Snow Simulator By GuitarGod1134
-- just simulates a snow weather condition
--color
white = Color.new(255,255,255)
--pics
snow = Image.create(10,10)
snow:clear(white)
background = Image.load("background.png")
--x = width y = hieght
snowxy = {}
snowxy[1] = { x = 30, y = -300}
snowxy[2] = { x = 200, y = -300}
snowxy[3] = { x = 110, y = -300}
snowxy[4] = { x = 97, y = -300}
snowxy[5] = { x = 400, y = -300}
snowxy[6] = { x = 300, y = -390}
snowxy[7] = { x = 250, y = -300}
--is the snow falling
falling = true
--main loop
while true do
screen:clear()
--blit the background
screen:blit(0,0,background)
--blit the snow
snowy = true
if snowy == true then
screen:blit(snowxy[1].x, snowxy[1].y, snow)
end
if snowy == true then
screen:blit(snowxy[2].x, snowxy[2].y, snow)
end
if snowy == true then
screen:blit(snowxy[3].x, snowxy[3].y, snow)
end
if snowy == true then
screen:blit(snowxy[4].x, snowxy[4].y, snow)
end
if snowy == true then
screen:blit(snowxy[5].x, snowxy[5].y, snow)
end
if snowy == true then
screen:blit(snowxy[6].x, snowxy[6].y, snow)
end
if snowy == true then
screen:blit(snowxy[7].x, snowxy[7].y, snow)
end
--make the snow fall
if falling == true then
snowxy[1].y = snowxy[1].y + 2
end
if falling == true then
snowxy[2].y = snowxy[2].y + 2
end
if falling == true then
snowxy[3].y = snowxy[3].y + 2
end
if falling == true then
snowxy[4].y = snowxy[4].y + 2
end
if falling == true then
snowxy[5].y = snowxy[5].y + 2
end
if falling == true then
snowxy[6].y = snowxy[6].y + 2
end
if falling == true then
snowxy[7].y = snowxy[7].y + 2
end
--now we reset them back to true so they can
--fall down again
if snowxy[6].y == 272 then
falling = false
end
--all the snow flakes
--are reset back
--to thier original
--y coordinates
if falling == false then
backup = true
snowxy[1].y = -300
snowxy[2].y = -300
snowxy[3].y = -300
snowxy[4].y = -300
snowxy[5].y = -300
snowxy[6].y = -390
snowxy[7].y = -300
end
--once they reach the bottom
--falling is declared true again
--so that it makes the affect
--that the snow is always falling
if backup == true then
falling = true
end
screen.waitVblankStart()
screen.flip
end

---

Ok when I try to run this I get this really annoying error that for some reason is common in a lot of games I try to make. The error is

error:script.lua:98: '=' expected near 'end'

and Im using windows lua player to test my games if that makes a difference.

And I know there might be some sloppy code in there or something I wrote it in 10 minutes with breakfast in my mind.

---

half of your code code be replaced with a for loop for a start.. replacing the 1,2,3,4,5,6 with c = 1 to 6 for example.

I cant see any errors in the code, (i dont know lua all that well) but maybe try the PSP Lua player.

And i dont think there is any special way to set a negative number. variable = -x should be fine.

How do I do things like
variable = 1 to 6 ?
And I tried it with psp lua player and I get the same exact error.

what does it mean when you get an error saying 'loop ingettable'. is that a memory related error? (i'm guessing so because i load ALOT of stuff in the beginning of my script.)

ok sincce im on christmas break im giving lua another shot but i ran across a problem. Im simply just trying to blit an image to te screen and it wont work. This were i always get stuck.:Argh:
heres my code:

Spoiler for code:

Code:

---

red = Color.new(255,0,0)
player = Image.load("a.png")
Player = {}
Player[1] = {x=200,y=50}
screen:blit(Player[1].x,Player[1].y,player)
screen.flip()
while true do
screen.waitVblankStart()
end

---

Zitat:

---

Zitat von %chrono trigger%

Spoiler for code:

Code:

---

red = Color.new(255,0,0)
player = Image.load("a.png")
Player = {}
Player[1] = {x=200,y=50}
while true do
screen:clear()
screen:blit(Player[1].x, Player[1].y, player)
screen.flip()
screen.waitVblankStart()
end

---

---

that SHOULD work...

Zitat:

---

Zitat von %chrono trigger%

ok sincce im on christmas break im giving lua another shot but i ran across a problem. Im simply just trying to blit an image to te screen and it wont work. This were i always get stuck.:Argh:
heres my code:

Spoiler for code:

Code:

---

red = Color.new(255,0,0)
player = Image.load("a.png")
Player = {}
Player[1] = {x=200,y=50}
screen:blit(Player[1].x,Player[1].y,player)
screen.flip()
while true do
screen.waitVblankStart()
end

---

---

i just tried it and it worked for me