Lua Programming Help Thread

[Gam3freQ]

Big problem. It won't work. here is post of source:

-- ******* RODM: Run or Die Mouse ********
-- This was Made by Mraellis And GamefreQ for your learning purposes. Please do not steal our work, but 
-- give us credit instead, and ask for our permission to use this.
dofile(Color.lua) --This directs to the color file for the colors of the text

-- Images

Bat = Image.load("Images/bat.png")
grass = Image.load("Images/grass.png")
Mouse7 = Image.load("Images/Mouse_UL.png")
Mouse9 = Image.load("Images/Mouse_UR.png")
Mouse8 = Image.load("Images/Mouse_U.png")
Mouse2 = Image.load("Images/Mouse_D.png")
Mouse4 = Image.load("Images/Mouse_L.png")
Mouse6 = Image.load("Images/Mouse_R.png")
Mouse1 = Image.load("Images/Mouse_DL.png")
Mouse3 = Image.load("Images/Mouse_DR.png")

screenwidth = 480 - player:width() -- These are so you cannot move your character off the screen
screenheight = 272 - player:width() -- because the PSP screen has 480 x 272 pixels :)

-- Tables (enemies and Players are here)

Player = { } Player[1] = { x = 200, y = 50 }

-- Sounds

Bat = Sound.load("Sounds/Bat.wav",false)
Mouse = Sound.load("Sounds/Mouse.wav",false)
Boom = Sound.load("Sounds/Boom.wav",false)
Chomp = Sound.load("Sounds/Chomp.wav",false)
heavyweight = Sound.load("Sounds/heavyweight.wav",false)
Shotgun = Sound.load("Sounds/Shotgun.wav",false)
Squash = Sound.load("Sounds/Squash.wav",false)
Levelstart = Sound.load("Sounds/Levelstart.wav",flase)

-- Vars

Win = screen:print(200, 100, "Well Done, You Won!", red)
Lose = screen:print(200, 100, "Sorry, You Lost!", blue)
Score = screen:print(200, 100, "Your score is", red)
MadeBy = screen:print(200, 100, "This Game was made by Mraellis And GamefreQ", blue)

-- Main loop

while true do
pad = Controls.read()
screen:clear()

for a = 0, 14 do
for b = 0,8 do
screen:blit(32 * a, 32 * b, grass)
end
end

screen:blit(Player[1].x,Player[1].y,Mouse8)

if pad:left() and Player[1].x > 0 then
Player[1].x = Player[1].x - 5
end

if pad:right() and Player[1].x < screenwidth then
Player[1].x = Player[1].x + 5
end

if pad:up() and Player[1].y > 0 then
Player[1].y = Player[1].y - 5
end

if pad:down() and Player[1].y < screenheight then
Player[1].y = Player[1].y + 5
end

screen.waitVblankStart()
screen.flip()
end

and here is post of error:

Error: SCRIPT.LUA:19: attempt to index global 'player' (a nil value)

Press start to restart

I don't understand. I have all of the files in the correct place (It is not done yet, no where near completion, but I just wanted to test it. but apparently not

[_-Tiger-_]

Aiight i think i might start coding lua then...if so il hafta save up for a laptop to code on lol

[Gam3freQ]

Aiight i think i might start coding lua then...if so il hafta save up for a laptop to code on lol

I was about 2g2 bed when I say that my thread was bumped up so I got a gleam of hope only to find this LOL no problemo though it's all cool but you can code with notepad on anything so I don't think you NEED to get a laptop jsut to code well gl

[_dysfunctional]

Big problem. It won't work. here is post of source:

-- ******* RODM: Run or Die Mouse ********
-- This was Made by Mraellis And GamefreQ for your learning purposes. Please do not steal our work, but 
-- give us credit instead, and ask for our permission to use this.
dofile(Color.lua) --This directs to the color file for the colors of the text

-- Images

Bat = Image.load("Images/bat.png")
grass = Image.load("Images/grass.png")
Mouse7 = Image.load("Images/Mouse_UL.png")
Mouse9 = Image.load("Images/Mouse_UR.png")
Mouse8 = Image.load("Images/Mouse_U.png")
Mouse2 = Image.load("Images/Mouse_D.png")
Mouse4 = Image.load("Images/Mouse_L.png")
Mouse6 = Image.load("Images/Mouse_R.png")
Mouse1 = Image.load("Images/Mouse_DL.png")
Mouse3 = Image.load("Images/Mouse_DR.png")

screenwidth = 480 - player:width() -- These are so you cannot move your character off the screen
screenheight = 272 - player:width() -- because the PSP screen has 480 x 272 pixels :)

-- Tables (enemies and Players are here)

Player = { } Player[1] = { x = 200, y = 50 }

-- Sounds

Bat = Sound.load("Sounds/Bat.wav",false)
Mouse = Sound.load("Sounds/Mouse.wav",false)
Boom = Sound.load("Sounds/Boom.wav",false)
Chomp = Sound.load("Sounds/Chomp.wav",false)
heavyweight = Sound.load("Sounds/heavyweight.wav",false)
Shotgun = Sound.load("Sounds/Shotgun.wav",false)
Squash = Sound.load("Sounds/Squash.wav",false)
Levelstart = Sound.load("Sounds/Levelstart.wav",flase)

-- Vars

Win = screen:print(200, 100, "Well Done, You Won!", red)
Lose = screen:print(200, 100, "Sorry, You Lost!", blue)
Score = screen:print(200, 100, "Your score is", red)
MadeBy = screen:print(200, 100, "This Game was made by Mraellis And GamefreQ", blue)

-- Main loop

while true do
pad = Controls.read()
screen:clear()

for a = 0, 14 do
for b = 0,8 do
screen:blit(32 * a, 32 * b, grass)
end
end

screen:blit(Player[1].x,Player[1].y,Mouse8)

if pad:left() and Player[1].x > 0 then
Player[1].x = Player[1].x - 5
end

if pad:right() and Player[1].x < screenwidth then
Player[1].x = Player[1].x + 5
end

if pad:up() and Player[1].y > 0 then
Player[1].y = Player[1].y - 5
end

if pad:down() and Player[1].y < screenheight then
Player[1].y = Player[1].y + 5
end

screen.waitVblankStart()
screen.flip()
end

and here is post of error:

Error: SCRIPT.LUA:19: attempt to index global 'player' (a nil value)

Press start to restart

I don't understand. I have all of the files in the correct place (It is not done yet, no where near completion, but I just wanted to test it. but apparently not

If you read the error that luaplayer gave you, you would see that on line 19 and 20 a variable called 'player' is used, yet it is not defined any where in the script. Remember, lua is case sensitive. 'Player' is not the same as 'player'. It is also linear, so things are interpreted from top to bottom.

-- Test Lua Application

T_Player[1].x = 10; -- Undefined table

T_Player = {} -- Table defined after table-menu

[Gam3freQ]

If you read the error that luaplayer gave you, you would see that on line 19 and 20 a variable called 'player' is used, yet it is not defined any where in the script. Remember, lua is case sensitive. 'Player' is not the same as 'player'. It is also linear, so things are interpreted from top to bottom.

-- Test Lua Application

T_Player[1].x = 10; -- Undefined table

T_Player = {} -- Table defined after table-menu

ok so also if I fix this then will my Player width and height be the same as Mouse8's width and height? (look at the code for Mouse8) Thank you for all of that

I also got an error on line 35: error loading sound, so I saw that it sad flase instead of false, so I fixed it, and I got the same error
-= Double Post =-
ZOMG! I downloaded colors.lua from evilmana.com and realized that there are NO SPACES! If there arn't any spaces then that means they won't work! Also they don't work without the spaces I tried! oh no! is there an alternate download with the spaces because that's a good 1000 colors that are now goin to waste

[michaelp]

yes it will....
the only thing spaces do are make your code look nicer

[Gam3freQ]

yes it will....
the only thing spaces do are make your code look nicer

no it gave me error dude


GhostWhite=Color.new(248, 248,255)
does not work BUT

GhostWhite = Color.new(248, 248, 255)

works perfectly and does NOT display error message so I said screw it and spaced out the ones I wanted to use and deleted the rest, and the program works, but I want to change the controls. I do NOT want it to be, up goes up, right goes right, left goes left, down goes down, etc. I want UP on the dpad to move your character whatever direction it is facing, and then left and right to turn or change the direction you're facing like in the flash game.

[coolguy5678]

You could have just used search-replace to fix the spaces...

[michaelp]

I'm having a bit of a problem with an image.
The image just looks like a button. (Sort of, not from the way I made it)
It has a black background, but when I blit it to the screen(without a background, or black) the background will show up as grey, not black.
I've tried using the True and false value's for the alpha, but same thing.
Anyone know why?

edit: nvm, fixed

[Da_MerV]

As for putting it into an image, for some reason using img:blit(0,0, screen) does not capture anything that was drawn with the Gu.

However, although I haven't tried it, I believe that if you use screen:save("screen.png") to save a screenshot to an image file, then you can load that image and use it like you would any other

i've been trying to find a way around this since saturday and i finally found one! yes its true that a screenshot will capture the scaled image but it would take way too long to write to the ms. remember the weird things that were happening with fillRect and print? well those weird things helped me to figure it out. when it blits from the screen, all it sees is alpha=0. when you fillRect or print before Gu.blit, it sees this as alpha=255. we can use this to our advantage to create masks! so in short, the quick fix is:

screen:fillRect(x,y,image:width(), image:height())

before the call to Gu.start3d()

[Gam3freQ]

You could have just used search-replace to fix the spaces...

tell me how

[_-Tiger-_]

Hows the game going? Im definatly gonna start learning Lua. I think ill start tomorrow, after i workout....gotta get ready for football lol

[a_noob]

Ok well i am not normally a Lua dev i would rather work with C/C++ any day but i have to work in Lua for a little while (if you are active at the luaplayer forums you would know what i am working on). Ok well i have setup the GU in the luaplayer and have it all working but i am wanting to run opacity on my objects so natuarally i enable GU_BLEND and run a normal Gu BlendFunc with (GU_ADD GU_SRC_ALPHA GU_ONE_MINUS_SRC_ALPHA) but my draw back is with the Luaplayer Color object i believe. I think that it does not support an alpha value. please correct me if im wrong but how would i go about having an Color object of an object drawn at ~50% opacity

EDIT====

MY BAD I OVER LOOKED IT ON THE DOCUMENTATIONS

[coolguy5678]

tell me how

Search-replace (you do know how to use search-replace, right?) "=" with " = " (without the quotes).

[Mraellis]

ok guys... we've been doing some work on it and we've hit a problem. the bat doesn't appear and u can go offscreen.

 -- ******* RODM: Run or Die Mouse ********
-- This was Made by Mraellis And GamefreQ for your learning purposes. Please do not steal our work, but 
-- give us credit instead, and ask for our permission to use this.

-- Colors

cyan = Color.new(0, 255, 255)
red1 = Color.new(255, 0, 0)
salmon1 = Color.new(255, 140, 105)
burlywood4 = Color.new(139, 115, 85)

math.randomseed(os.time()) --/// prevent same random numbers from occuring each run of the game///

-- Images

Bat = Image.load ("Images/bat.png")
grass = Image.load("Images/Grass.png")
Mouse7 = Image.load("Images/Mouse_UL.png")
Mouse9 = Image.load("Images/Mouse_UR.png")
Mouse8 = Image.load("Images/Mouse_U.png")
Mouse2 = Image.load("Images/Mouse_D.png")
Mouse4 = Image.load("Images/Mouse_L.png")
Mouse6 = Image.load("Images/Mouse_R.png")
Mouse1 = Image.load("Images/Mouse_DL.png")
Mouse3 = Image.load("Images/Mouse_DR.png")

-- Sounds

Bat = Sound.load("Sounds/Bat.wav",false)
Mouse = Sound.load("Sounds/Mouse.wav",false)
Boom = Sound.load("Sounds/Boom.wav",false)
Chomp = Sound.load("Sounds/Chomp.wav",false)
heavyweight = Sound.load("Sounds/heavyweight.wav",false)
Shotgun = Sound.load("Sounds/Shotgun.wav",false)
Squash = Sound.load("Sounds/Squash.wav",false)
Levelstart = Sound.load("Sounds/Levelstart.wav",false)

-- Vars

Win = screen:print(200, 100, "Well Done, You Won!", red1)
Lose = screen:print(200, 100, "Sorry, You Lost!", cyan)
Score = screen:print(200, 100, "Your score is", salmon1)
MadeBy = screen:print(200, 100, "This Game was made by Mraellis And GamefreQ", burlywood4)

-- Tables (enemies and Players are here)

Player = { } Player = { x = 200, y = 50 }
Enemy = { } Enemy = { x = 50, y = 50 }

screenwidth = 480 - Mouse8:width() -- These are so you cannot move your character off the screen
screenheight = 272 - Mouse8:height() -- because the PSP screen has 480 x 272 pixels :)

function movePlayer() --/// function to move our player when directionals are pressed///
pad = Controls.read()
if pad:left() then
Player.x = Player.x - 5
end
if pad:right() then
Player.x = Player.x + 5
end
if pad:up() then
Player.y = Player.y - 5
end
if pad:down() then
Player.y = Player.y + 5
end
end

function chasePlayer() --/ function to make the enemy chase the player/
stallchase = math.random(2) 
if stallchase == 1 then 
if Enemy.x > Player.x then
Enemy.x = Enemy.x - 2
elseif Enemy.x < Player.x then
Enemy.x = Enemy.x + 2
end
end
stallchase = math.random(2)
if stallchase == 1 then
if Enemy.y > Player.y then
Enemy.y = Enemy.y - 2
elseif Enemy.y < Player.y then
Enemy.y = Enemy.y + 2
end
end
end --///end the function///

-- Main loop

while true do
screen:clear()

for a = 0, 14 do
for b = 0,8 do
screen:blit(32 * a, 32 * b, grass)
end
end

screen:blit(Player.x,Player.y,Mouse8)
screen:blit(Enemy.x,Enemy.y,Bat)

movePlayer() --///call movePlayer function///

chasePlayer() --///call chasePlayer function////

screen.waitVblankStart()
screen.flip()
end

can someone help plz.

[Mraellis]

ok guys... we've been doing some work on a game and we've hit a problem. the bat doesn't appear and u can go offscreen.

 -- ******* RODM: Run or Die Mouse ********
-- This was Made by Mraellis And GamefreQ for your learning purposes. Please do not steal our work, but 
-- give us credit instead, and ask for our permission to use this.

-- Colors

cyan = Color.new(0, 255, 255)
red1 = Color.new(255, 0, 0)
salmon1 = Color.new(255, 140, 105)
burlywood4 = Color.new(139, 115, 85)

math.randomseed(os.time()) --/// prevent same random numbers from occuring each run of the game///

-- Images

Bat = Image.load ("Images/bat.png")
grass = Image.load("Images/Grass.png")
Mouse7 = Image.load("Images/Mouse_UL.png")
Mouse9 = Image.load("Images/Mouse_UR.png")
Mouse8 = Image.load("Images/Mouse_U.png")
Mouse2 = Image.load("Images/Mouse_D.png")
Mouse4 = Image.load("Images/Mouse_L.png")
Mouse6 = Image.load("Images/Mouse_R.png")
Mouse1 = Image.load("Images/Mouse_DL.png")
Mouse3 = Image.load("Images/Mouse_DR.png")

-- Sounds

Bat = Sound.load("Sounds/Bat.wav",false)
Mouse = Sound.load("Sounds/Mouse.wav",false)
Boom = Sound.load("Sounds/Boom.wav",false)
Chomp = Sound.load("Sounds/Chomp.wav",false)
heavyweight = Sound.load("Sounds/heavyweight.wav",false)
Shotgun = Sound.load("Sounds/Shotgun.wav",false)
Squash = Sound.load("Sounds/Squash.wav",false)
Levelstart = Sound.load("Sounds/Levelstart.wav",false)

-- Vars

Win = screen:print(200, 100, "Well Done, You Won!", red1)
Lose = screen:print(200, 100, "Sorry, You Lost!", cyan)
Score = screen:print(200, 100, "Your score is", salmon1)
MadeBy = screen:print(200, 100, "This Game was made by Mraellis And GamefreQ", burlywood4)

-- Tables (enemies and Players are here)

Player = { } Player = { x = 200, y = 50 }
Enemy = { } Enemy = { x = 50, y = 50 }

screenwidth = 480 - Mouse8:width() -- These are so you cannot move your character off the screen
screenheight = 272 - Mouse8:height() -- because the PSP screen has 480 x 272 pixels :)

function movePlayer() --/// function to move our player when directionals are pressed///
pad = Controls.read()
if pad:left() then
Player.x = Player.x - 5
end
if pad:right() then
Player.x = Player.x + 5
end
if pad:up() then
Player.y = Player.y - 5
end
if pad:down() then
Player.y = Player.y + 5
end
end

function chasePlayer() --/ function to make the enemy chase the player/
stallchase = math.random(2) 
if stallchase == 1 then 
if Enemy.x > Player.x then
Enemy.x = Enemy.x - 2
elseif Enemy.x < Player.x then
Enemy.x = Enemy.x + 2
end
end
stallchase = math.random(2)
if stallchase == 1 then
if Enemy.y > Player.y then
Enemy.y = Enemy.y - 2
elseif Enemy.y < Player.y then
Enemy.y = Enemy.y + 2
end
end
end --///end the function///

-- Main loop

while true do
screen:clear()

for a = 0, 14 do
for b = 0,8 do
screen:blit(32 * a, 32 * b, grass)
end
end

screen:blit(Player.x,Player.y,Mouse8)
screen:blit(Enemy.x,Enemy.y,Bat)

movePlayer() --///call movePlayer function///

chasePlayer() --///call chasePlayer function////

screen.waitVblankStart()
screen.flip()
end

can someone help plz.

[Urameshi]

because you have a bat image, and a bat sound that are named the same

[michaelp]

you never put in a function or anything so that the bat/mouse can't go offscreen
also, with all those sounds and pictures, don't you get some sort of memory error, or the game is a bit slow?
also, a suggestion for your "movePlayer" function: make it less than + or - 5, that (i think) will be quite choppy

Your variables should be:
1. functions
or
2. just words

I'm pretty sure you can't be a built-in luaplayer function in a variable
just put the words you want in, and when you want to print it to the screen, do this:
screenrint(x, y, variable, colour)

[Gam3freQ]

yes it will....
the only thing spaces do are make your code look nicer

DONT ARGUE. it doesn't work i have tred it OK?! also look at the post above and help us with that source code somebody, and I do not know how to do "find and replace" or w/e

[Mraellis]

i'll explain f & r later

[Gam3freQ]

i'll explain f & r later

oh ok
:Punk:

[_-Tiger-_]

Hey does anyone know how to edit my code while having it on my psp w/o exiting Luaplayer? I've tried this

System.usbDiskModeActivat e()

But i cant edit my code... any help?

Edit: Ok im following tutorial #2 from psp-programming.com and when i try it i says
Error SCRPIT.LUA:130: /=/ expected near /pad/. Any help?

[Gam3freQ]

Hey does anyone know how to edit my code while having it on my psp w/o exiting Luaplayer? I've tried this

System.usbDiskModeActivat e()

But i cant edit my code... any help?

Edit: Ok im following tutorial #2 from psp-programming.com and when i try it i says
Error SCRPIT.LUA:130: /=/ expected near /pad/. Any help?

look at line 130 in your code

[_-Tiger-_]

I did i tried to fix it about 10 times and still nothing... lol

[Mraellis]

post the full code and we can see where the problem is

[Merick]

i've been trying to find a way around this since saturday and i finally found one! yes its true that a screenshot will capture the scaled image but it would take way too long to write to the ms. remember the weird things that were happening with fillRect and print? well those weird things helped me to figure it out. when it blits from the screen, all it sees is alpha=0. when you fillRect or print before Gu.blit, it sees this as alpha=255. we can use this to our advantage to create masks! so in short, the quick fix is:

screen:fillRect(x,y,image:width(), image:height())

before the call to Gu.start3d()

Thanks for the tip, I was wondering about that.

Also, here's Gu.blit2:

function Gu.blit2(x, y, image, img_x, img_y, width, height, scale, flip)
	
	if not scale or type(scale) == "string" then 
		flip = scale
		scale = 1
	end
	
	
	if flip then
		if flip == "H" then
			x_start = img_x + width
			y_start = img_y
			x_end  = img_x
			y_end = img_y + height
		elseif  flip == "V" then
			x_start = img_x
			y_start = img_y + height
			x_end  = img_x + width
			y_end = img_y
		elseif flip == "HV" then
			x_start = img_x + width
			y_start = img_y + height
			x_end = img_x
			y_end = img_y
		end
	else
		x_start = img_x
		y_start = img_y
		x_end = img_x + width
		y_end = img_y + height
	end
	
	
	
	
	width = (width*scale)+y or (image:width()*scale)+x
	height = (height*scale)+y or (image:height()*scale)+y
	temp = {
	{x_start, y_start, x, y, 0},
	{x_end, y_end, width, height, 0}
	}
	Gu.enable(Gu.TEXTURE_2D)
	Gu.texImage(image)
	Gum.drawArray(Gu.SPRITES, Gu.TEXTURE_32BITF+Gu.VERTEX_32BITF+Gu.TRANSFORM_2D, temp)
end

it's basically the same as the first Gu.blit, except this version can draw parts of the image:

Gu.blit2(10, 10, image, 10, 10, 40, 90, 1.5, "HV")

[EminentJonFrost]

Hey does anyone know how to edit my code while having it on my psp w/o exiting Luaplayer? I've tried this

System.usbDiskModeActivat e()

But i cant edit my code... any help?

Edit: Ok im following tutorial #2 from psp-programming.com and when i try it i says
Error SCRPIT.LUA:130: /=/ expected near /pad/. Any help?

are you sure you completely exited your app or game and were in Lowser when trying to edit your code?

[Anti-QuickJay]

Once you edit your going to need to quit your game and restart lowser.

[EminentJonFrost]

Once you edit your going to need to quit your game and restart lowser.

you dont need to restart lowser, just exit the app then restart the app after editing it.

[Anti-QuickJay]

Thats if you include a exit call.