Lua Programming Help Thread

I still get this error - "attempt to index global 'mouse' <a nil value>

1 moe queston: how would i make collision for a stick figure?? would i have to do it in seperate parts? :confused: thx.

Zitat:

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Zitat von c5cha7

I am looking for the same thing :icon_wink .
I found a site that has .mod sounds though >
http://www.modarchive.com/

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I found a site http://simplythebest.net/sounds/WAV/WAV_sounds.html

Zitat:

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Zitat von Grimfate126

1 moe queston: how would i make collision for a stick figure?? would i have to do it in seperate parts? :confused: thx.

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i have done if for my game. u just cant use the magic wand tool in photohop. it has to be rectangular. the collision still works fine tho

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Zitat von MaSt3r_ShAk3

i have done if for my game. u just cant use the magic wand tool in photohop. it has to be rectangular. the collision still works fine tho

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??? huh? my stik figure has a round head. i want it so that when u shoot a bullet at a certain part, and it HITS the part,(thats where the collisions come in)then, it will do something. so how would u do that for a circle. sry, if i sound confusing. thx


P.S. to montrob, try this:

Code:

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background = Image.load("background.png")
mouse1 = Image.load("mouse1.png")

mouse.x = 100
mouse.y = 272

while true do

screen:blit(0, 0, background, false)
screen:blit(mouse.x, mouse.y, mouse1)

pad = Controls.read

if pad:up() then
mouse.y = mouse.y + 1
end

if pad:down() then
mouse.y = mouse.y - 1
end

if pad:left() then
mouse.x = mouse.x - 1
end

if pad:right() then
mouse.x = mouse.x + 1
end

screen.waitVblankStart()
screen:flip()
end

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Zitat:

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Zitat von Grimfate126

??? huh? my stik figure has a round head. i want it so that when u shoot a bullet at a certain part, and it HITS the part,(thats where the collisions come in)then, it will do something. so how would u do that for a circle. sry, if i sound confusing. thx


P.S. to montrob, try this:

Code:

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background = Image.load("background.png")
mouse1 = Image.load("mouse1.png")

mouse.x = 100
mouse.y = 272

while true do

screen:blit(0, 0, background, false)
screen:blit(mouse.x, mouse.y, mouse1)

pad = Controls.read

if pad:up() then
mouse.y = mouse.y + 1
end

if pad:down() then
mouse.y = mouse.y - 1
end

if pad:left() then
mouse.x = mouse.x - 1
end

if pad:right() then
mouse.x = mouse.x + 1
end

screen.waitVblankStart()
screen:flip()
end

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Didn't work.. every time i try to do something i get this error

"attempt to index global 'mouse' <a nil value>"

What does that mean?

Ok umm, i need help making sounds play when i die...

Code:

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ballsound = Sound.load("blip.wav", false)
deathsound = Sound.load("magnum.wav", false)

deathsound = death
ballsound = ball
voice = sound:play()

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i get "attempt to index global 'voice' (a nil value)"

your sound variable isnt defined. nothing is assigned to it.
Also what are "death" and "ball"?
You already assigned ballsound and deathsound a value, so what are those that you are assigning directly after?
Try something like this...

Code:

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ballsound = Sound.load("blip.wav", false)
deathsound = Sound.load("magnum.wav", false)

 local sound = deathsound
voice = sound:play()

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Zitat:

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Zitat von montrob

Didn't work.. every time i try to do something i get this error

"attempt to index global 'mouse' <a nil value>"

What does that mean?

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oh, my bad. i figured it out.the correct code:

Code:

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

background = Image.load("background.png")
mouse = Image.load("mouse1.png")

mousex = 100
mousey = 172

while true do

screen:clear()

pad = Controls.read()

screen:blit(0, 0, background, false)
screen:blit(mousex, mousey, mouse)

if pad:up() then
mousey = mousey - 1
end

if pad:down() then
mousey = mousey + 1
end

if pad:left() then
mousex = mousex - 1
end

if pad:right() then
mousex = mousex + 1
end

screen.waitVblankStart()
screen.flip()
end

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the problems:

1. the variable mouse.x and mouse.y both have periods in them. is LUA, that means that you are assigning those values to an array. EXAMPLE: if i had an array like this:

Code:

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mouse = {}

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and then i put mouse.x = 100 and mouse.y= 170 in my code, and started it, the array would now look like this:

Code:

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mouse = { x = 100, y = 170}

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BUT, you didnt have an array so it called it a "nil" value, and gave you an error. get what im saying??

2. u had the variables BEFORE the loading. this is'nt so much a problem, but it could interfere with the coding. so ALWYS load everything first, THEN have the variables, THEN your main code.

3. thisis just a tip: evertime you are blitting the same thing to the screen, NEVER put screen:flip() before each time you blit it. this will cause clipping problems. just put

Code:

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screen.waitVblankStart()
screen.flip()
end

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at the VERY END of your code, IN the main loop.


thats all i saw! hope u understood ur problems, and good luck with whatever ur doing!!:D:D:D

EDIT: PSPMILLIONAIRE, could u help me with my collisions? read my above posts to see the problem i have. thx!

Grim you will have to use what is called "pixel perfect collision" .
There are solutions for doing this posted all over the internet. Find an example with a simple BASIC language. It will be very much like lua.