Lua Programming Help Thread

[Grimfate126]

ok. this is to ALL CODERS. i have seen a lot of code such as:

screen:print(100, 130, "blah", red)
screen:flip()

if you put this code:

screen.waitVblankStart()
screen.flip()
end

at the VERRRYYYY END of your codem you dont have to worry about screen:flip() for your ENTIRE CODE. it becomes much easier that way.

[PSPHax0r9]

Umm...I'm having a slight problem. Is there any way to "pause" a loop? I ask this because I have an options menu that comes up whenever you press start, the only problem is that when it comes up, the player will keep moving while the menu is up. The menu actually has its own loop because of some stuff I added in there, but this still happens no matter what I do. Does anyone have any suggestions? Thanks guys.

[montrob]

Ive never done it but you could try this

while not pad:start() do
-- main loop --
end

if pad:start() then
--menu --
end

[Grimfate126]

Umm...I'm having a slight problem. Is there any way to "pause" a loop? I ask this because I have an options menu that comes up whenever you press start, the only problem is that when it comes up, the player will keep moving while the menu is up. The menu actually has its own loop because of some stuff I added in there, but this still happens no matter what I do. Does anyone have any suggestions? Thanks guys.

you could have a boolean:

pause = false

then:

if pause == false then
--the code for you character moving..etc
end

after:

if pad:start() and pause == false then
pause = true
end

and finally:

if pause == true then
--your menu code
end

if pad:start() and pause == true then
pause = false
end

try it out.

[PSPHax0r9]

Yea, that's what I was planning on doing but I just wanted to know if there was a simple command I was missing so I wouldn't have to cater my whole game around the options menu.

[natan333]

Look

if true then
screen:blit(x1, y1, player2)
x1 = x1 + 2 
end

if true and pause == true then

screen:blit(x0, y0, up2)
screen.flip()
screen.waitVblankStart(10)

screen:blit(x0, y0, up1)
screen.flip()
screen.waitVblankStart(10)

y0 = y0 - 2 
end


if pad:up() then
pause = true
end

This is a better example.

picture "player2" will atomatically move right.
If i press Up, It will not move smooth and will start to skip some pixels

The good thing i liked about the "screen.waitVblankStart(1 0)" is that it makes picture "up1" and "up2" to keep changing atomatically.

The bad thing is that "screen.waitVblankStart(1 0)" Makes picture "player2" movement and the picture "up1" and "up2" movement not smooth and skipping some pixels.

My question is:
Is there a way to fix the bad thing ?

[montrob]

Hey, a notepad question.. If you go to Edit.. theres an option called GoTo.. This option allows you to go to a certain line in the text, but when i try to click on it nothing happens.. any help?

[TheMarioKarters]

Hey, a notepad question.. If you go to Edit.. theres an option called GoTo.. This option allows you to go to a certain line in the text, but when i try to click on it nothing happens.. any help?

I have the same problem.

[montrob]

I have the same problem.

Figured it out! Just go to View and uncheck Word Wrap. Then it works.

[TheMarioKarters]

Figured it out! Just go to View and uncheck Word Wrap. Then it works.

Ah, thanks mate.

[SG57]

ok my new game is going to be a car game. i want to know how you would make it so if you hit the top, bottom, or sides of the other car your health is decreased. how would i do that?

Collision..

Im planning on making a lib for questions asked alot that will be available to all... it will be a simple function... converted from my C to LUA (ravine). then maybe add rotation adn such... I dunno still... maybe someone else is maing somethin alike to it? that i could just addthe collision to it.

[Altair]

well I know that in LUA-player 0.19 there is a function that lets you rotate images.

A collision lib would be very nice.

[Altair]

Umm...I'm having a slight problem. Is there any way to "pause" a loop? I ask this because I have an options menu that comes up whenever you press start, the only problem is that when it comes up, the player will keep moving while the menu is up. The menu actually has its own loop because of some stuff I added in there, but this still happens no matter what I do. Does anyone have any suggestions? Thanks guys.

If you use a function for your menu, and there's a loop in it then everything will pause except for timers. This is how i do it and it works perfectly.
This is also logical, since when the program is in the menu loop it cant run in the game loop.

[EminentJonFrost]

Umm...I'm having a slight problem. Is there any way to "pause" a loop? I ask this because I have an options menu that comes up whenever you press start, the only problem is that when it comes up, the player will keep moving while the menu is up. The menu actually has its own loop because of some stuff I added in there, but this still happens no matter what I do. Does anyone have any suggestions? Thanks guys.

Use a new function, like Altair said.
It'll pause whatever you have running, then when it breaks, it'll go back to whatever to you were doing before pausing.

[montrob]

OK i need to make my game so that you have to press the button more than once to blow up all the bombs EX - There are 2 circle bombs, right now if you hit circle both blow up, but I need it so that you have to hit circle twice for each one to blow up!

[Altair]

Depends on how you have your bombs made. Im assuming you use a table.

Just say that if you you press circle ones, make the bomb[n] blow up. And each time you press circle add 1 to n.

[montrob]

Depends on how you have your bombs made. Im assuming you use a table.

Just say that if you you press circle ones, make the bomb[n] blow up. And each time you press circle add 1 to n.

Ya it works.. Almost ready for a public beta of my game!

[slicer4ever]

question!!!(sorry just thought i make myself clear) is their anyway to attach an image to another image without going into a the image and manually because this would make scrolling for my game easyier

--thanks in advance

[Vaza]

?
U mean like create a image canvas that is double the length of your map and blit both oin there, cos i think thats possible.
?

[slicer4ever]

no i mean so i can scroll my map and the other images are attached to my map so they scroll with it else i well have to set them all to scroll individually but if i can attach them to my main map then it all works out=-)

[SG57]

Ohh... i understand... theres multiple ways...

[EminentJonFrost]

I'm just making a for-fun script that has a visual effect, well, what I'm trying to achieve is a visual effect.

an error that keeps popping up: lua: 36 : argument was incorrect

heres my short script:

black = Color.new(0, 0, 0)
white = Color.new(255, 255, 255)
red = Color.new(255, 0, 0)
green = Color.new(0, 255, 0)
blue = Color.new(0, 0, 255)

width = 480
height = 272

while true do

pad = Controls.read()

if pad:cross() then
break
end

screen:clear(black)

h = math.random(1, 100)

x = width/h
y = height/h

z = math.random(1, 4)

if z == 1 then
screen:pixel(x, y, white)
end

if z == 2 then
screen:pixel(x, y, red)
end

if z == 3 then
screen:pixel(x, y, green) -- this is line 36
end

if z == 4 then
screen:pixel(x, y, blue)
end

screen.flip()
screen.waitVblankStart()
end

whats wrong?

[Grimfate126]

I'm just making a for-fun script that has a visual effect, well, what I'm trying to achieve is a visual effect.

an error that keeps popping up: lua: 36 : argument was incorrect

heres my short script:

black = Color.new(0, 0, 0)
white = Color.new(255, 255, 255)
red = Color.new(255, 0, 0)
green = Color.new(0, 255, 0)
blue = Color.new(0, 0, 255)

width = 480
height = 272

while true do

pad = Controls.read()

if pad:cross() then
break
end

screen:clear(black)

h = math.random(1, 100)

x = width/h
y = height/h

z = math.random(1, 4)

if z == 1 then
screen:pixel(x, y, white)
end

if z == 2 then
screen:pixel(x, y, red)
end

if z == 3 then
screen:pixel(x, y, green) -- this is line 36
end

if z == 4 then
screen:pixel(x, y, blue)
end

screen.flip()
screen.waitVblankStart()
end

whats wrong?

try this:

math.randomseed(os.time())

black = Color.new(0, 0, 0)
white = Color.new(255, 255, 255)
red = Color.new(255, 0, 0)
green = Color.new(0, 255, 0)
blue = Color.new(0, 0, 255)

width = 480
height = 272

h = math.random(1, 100)
z = math.random(1, 4)

x = width/h
y = height/h


while true do

pad = Controls.read()

if pad:cross() then
break
end

screen:clear()

if z == 1 then
screen:pixel(x, y, white)
elseif z == 2 then
screen:pixel(x, y, red)
elseif z == 3 then
screen:pixel(x, y, green)
elseif z == 4 then
screen:pixel(x, y, blue)
end

screen.flip()
screen.waitVblankStart()
end

you should use elseif statemnts, they lower the chance of an error bigtime.

[ZereoX]

how can i do

if player.y == 138(pixel on my screen) then gravity = 138 so tha when i jump i don't past trugh the floor. cause the floor im jumping on is higher

[EminentJonFrost]

how can i do

if player.y == 138(pixel on my screen) then gravity = 138 so tha when i jump i don't past trugh the floor. cause the floor im jumping on is higher

you need to post a little more coding up.

[ZereoX]

Here is the part of my code

player = {}
player.gravity = 160
player.y = 230
player.x = 50
player.jumpspeed = 10
player.jumpstate = "ground"


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

screen:blit(0,0,Background1)

if pad:r() and oldpad:r() ~= pad:r() then
bulletSetup()
end


if pad:left() then
player.x = player.x - 2
end
if pad:right() then
player.x = player.x + 2
end

if pad:cross() and player.jumpstate == "ground" then player.jumpstate = "jumping" end

if player.jumpstate == "jumping" then
player.jumpspeed = player.jumpspeed - 0.5
player.gravity = player.gravity - player.jumpspeed
end

if player.gravity < 0 then
player.jumpstate = "falling"
end

if player.gravity < 160 and player.jumpstate == "falling" then
player.gravity = player.gravity + (player.jumpspeed + 3)
end

if player.gravity == 160 then
player.jumpspeed = 10
player.jumpstate = "ground"
end

if player.gravity > 160 then player.gravity = 160 end

player.y = player.gravity

screen:blit(player.x,player.y,player1)
screen:blit(0,0,ground)

i want to do when the legs of the player that mean the player.y touches the floor where its higher then the normal floor the gravity changes so that he stay on and not pass true it up to the same high as the prvious floor.

[EminentJonFrost]

player = {}
player.gravity = 160
player.y = 230
player.x = 50
player.jumpspeed = 10
player.jumpstate = "ground"


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

screen:blit(0,0,Background1)

if pad:r() and oldpad:r() ~= pad:r() then
bulletSetup()
end


if pad:left() then
player.x = player.x - 2
end
if pad:right() then
player.x = player.x + 2
end

if pad:cross() and player.jumpstate == "ground" then player.jumpstate = "jumping" end

if player.jumpstate == "jumping" then
player.jumpspeed = player.jumpspeed - 0.5
player.gravity = player.gravity - player.jumpspeed
end

if player.gravity < 0 then
player.jumpstate = "falling"
end

if player.gravity < 160 and player.jumpstate == "falling" then
player.gravity = player.gravity + (player.jumpspeed + 3)
end

if player.gravity == 160 then
player.jumpspeed = 10
player.jumpstate = "ground"
end

if player.gravity > 160 then player.gravity = 160 end

player.y = player.gravity

screen:blit(player.x,player.y,player1)
screen:blit(0,0,ground)

second_floor = {}
second_floor.y = 220 -- made it lower, just in case the player cant reach.
second_floor.x1 = 100
second_floor.x2 = 200

if player.y <= second_floor.y and player.x >= second_floor.x1 and player.x <= second_floor.x2  then
player.y = second_floor.y -- I forgot the ".y" last time.
end

try it now.
i made two changes from the last time, one correcting a stupid mistake on my part.

[ZereoX]

does't work it don't even change somthing.
Want me to send everything or you still have.

[montrob]

does't work it don't even change somthing.
Want me to send everything or you still have.

Well instead of changing player.gravity you could say

 if player.y >= 138 then
player.y = 138

[natan333]

if true then
screen:blit(x1, y1, player2)
x1 = x1 + 2 
end

if true and pause == true then

screen:blit(x0, y0, up2)
screen.flip()
screen.waitVblankStart(10  )

screen:blit(x0, y0, up1)
screen.flip()
screen.waitVblankStart(10  )

y0 = y0 - 2 
end


if pad:up() then
pause = true
end

noone yet helped me yet, (i think noone knows how to fix it).
anyways, is there a way to make the up1 and up2 change after each move?