Lua Scripts/Examples/Snippets

[yaustar]

Yes, especially in Lua (because it is a dynamically typed language) you can do this:

color = Color.new;
pad = Controls.read;

-- use
red = color( 255, 0, 0 );
curentPadState = pad();

[FaT3oYCG]

this will let you check for a file

assert()

so to make a file check function

function file_check(file_path)
file = assert(io.open(file_path))
if file == nil then
screen:print(10, 10, "the file path was invalid")
else
screen:print(10, 10, "the file path was valid")
end
end

by using assert there is no need to actually open the file or close it so it should be much quicker

you can also return custom error messages using this command and create an error handler for your programs

- i dont have an example error handler but this is sort of how assert is used

if condition then
assert(test, "message")
end

this code means that if the condition is met then it will carry out the assert command so say if file == nil then you would use

if file == nil then
assert(file == nil, "this file is invalid")
end

if there is no message then the command can be used to check values and will return either false or nil so if the error or condition is false it wont be executed, but if it is nill it will assert the command given

- an example of this is the code used at the top of my post

that is the part of the code that is seen as the test

io.open(file_path)

in the top post no message was passed

the error messages come out the same was as if an error is returned in lua player with a black screen and a white error message

thanks

[FaT3oYCG]

oh here is a handy little charge bar function i made all you need to do is put this

above while true do

function charge_bar_horizontal(xpos, ypos)

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

Charge = {}
Charge.percentage = System.powerGetBatteryLifePercent()

screen:fillRect(xpos, ypos, 138, 12, white)
screen:fillRect(xpos + 1, ypos + 1, Charge.percentage, 10, green)
screen:drawLine(xpos + 1, ypos + 1, xpos + 1, ypos + 10, black)
screen:drawLine(xpos + 11, ypos + 1, xpos + 11, ypos + 10, black)
screen:drawLine(xpos + 21, ypos + 1, xpos + 21, ypos + 10, black)
screen:drawLine(xpos + 31, ypos + 1, xpos + 31, ypos + 10, black)
screen:drawLine(xpos + 41, ypos + 1, xpos + 41, ypos + 10, black)
screen:drawLine(xpos + 51, ypos + 1, xpos + 51, ypos + 10, black)
screen:drawLine(xpos + 61, ypos + 1, xpos + 61, ypos + 10, black)
screen:drawLine(xpos + 71, ypos + 1, xpos + 71, ypos + 10, black)
screen:drawLine(xpos + 81, ypos + 1, xpos + 81, ypos + 10, black)
screen:drawLine(xpos + 91, ypos + 1, xpos + 91, ypos + 10, black)
screen:drawLine(xpos + 101, ypos + 1, xpos + 101, ypos + 10, black)

screen:fillRect(xpos + 104, ypos + 1, 33, 10, black)

screen:print(xpos + 106, ypos + 2, Charge.percentage .. "%", white)

end

and then to use it it only takes two arguments and x co-ordinate and a y co-ordinate like this

charge_bar_horizontal(10, 10)

if you wanted to blit it to an empty image that has been created then you could use this

function charge_bar_horizontal(display, xpos, ypos)

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

Charge = {}
Charge.percentage = System.powerGetBatteryLifePercent()

display:fillRect(xpos, ypos, 138, 12, white)
display:fillRect(xpos + 1, ypos + 1, Charge.percentage, 10, green)
display:drawLine(xpos + 1, ypos + 1, xpos + 1, ypos + 10, black)
display:drawLine(xpos + 11, ypos + 1, xpos + 11, ypos + 10, black)
display:drawLine(xpos + 21, ypos + 1, xpos + 21, ypos + 10, black)
display:drawLine(xpos + 31, ypos + 1, xpos + 31, ypos + 10, black)
display:drawLine(xpos + 41, ypos + 1, xpos + 41, ypos + 10, black)
display:drawLine(xpos + 51, ypos + 1, xpos + 51, ypos + 10, black)
display:drawLine(xpos + 61, ypos + 1, xpos + 61, ypos + 10, black)
display:drawLine(xpos + 71, ypos + 1, xpos + 71, ypos + 10, black)
display:drawLine(xpos + 81, ypos + 1, xpos + 81, ypos + 10, black)
display:drawLine(xpos + 91, ypos + 1, xpos + 91, ypos + 10, black)
display:drawLine(xpos + 101, ypos + 1, xpos + 101, ypos + 10, black)

display:fillRect(xpos + 104, ypos + 1, 33, 10, black)

display:print(xpos + 106, ypos + 2, Charge.percentage .. "%", white)

end

then to use that

blank_image = Image.createEmpty(200, 200)
blank_image:clear()

screen:blit(10, 10, blank_image)

charge_bar_horizontal(blank_image, 10, 10)

EDIT:

here is what it looks like


thanks

[TurtlesPwn]

simpler less cpu-using charge function that only redraws the battery bar when the battery life goes down enough to change the size of the bar:

cb = {w = 100, h = 10,c = Color.new(255,0,0)}
cb.i = Image.createEmpty(cb.w,cb.h)
cb.lbpc = (cb.w+2)*(100/cb.w)
function updateCB()
	cb.bp = System.getBatteryLifePercent()
	if math.abs(cb.lbpc-cb.bp)*100 >= cb.w then
		cb.lbpc = cb.bp
		cb.i:clear()
		cb.i:fillRect(0,0,cb.w*cb.bp/100,cb.h,cb.c)
	end
end

[FaT3oYCG]

here is the code for a menu that is as simple as i can get it at the moment

-- to add more items variables need to be changed and to accept input more code must be added but if you run this code you will see what it does and why it is simple

white = Color.new(255,255,255)
red = Color.new(255,0,0)

option = { "spot - 1 -", "spot - - 2 - -", "spot - - - 3 - - -" }

current = 1

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

for i = 1, 3 do
screen:print(10, 10 * i, option[i], white)
screen:print(10, 10 * current, option[current], red)
end

if pad:up() and oldpad:up() ~= pad:up() and current > 1 then
current = current - 1
end
if pad:down() and oldpad:down() ~= pad:down() and current < 3 then
current = current + 1
end

screen.flip()
screen.waitVblankStart()

oldpad = pad

end

and here is a very advanced menu code that uses functions for the variable values to save time for the coder

white = Color.new(255,255,255)
red = Color.new(255,0,0)

option = { "spot - 1 -", "spot - - 2 - -", "spot - - - 3 - - -" }

current = 1

function menu_setup(table_name, start_index, end_index)
for i = start_index, end_index do
screen:print(10, 10 * i, table_name[i], white)
screen:print(10, 10 * current, table_name[current], red)
end
end

function menu_controls(min_index, max_index)
if pad:up() and oldpad:up() ~= pad:up() and current > min_index then
current = current - 1
end
if pad:down() and oldpad:down() ~= pad:down() and current < max_index then
current = current + 1
end
end

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

menu_setup(option, 1, 3)
menu_controls(1, 3)

screen.flip()
screen.waitVblankStart()

oldpad = pad

end

use that if you want it straight in your code and a layout like this if you want it in a separate file - you need to use pad and oldpad or change the menu.lua file corresponding to what you have used instead of pad and oldpad

menu.lua

function menu_setup(table_name, start_index, end_index)
for i = start_index, end_index do
screen:print(10, 10 * i, table_name[i], white)
screen:print(10, 10 * current, table_name[current], red)
end
end

function menu_controls(min_index, max_index)
if pad:up() and oldpad:up() ~= pad:up() and current > min_index then
current = current - 1
end
if pad:down() and oldpad:down() ~= pad:down() and current < max_index then
current = current + 1
end
end

index.lua

white = Color.new(255,255,255)
red = Color.new(255,0,0)

option = { "spot - 1 -", "spot - - 2 - -", "spot - - - 3 - - -" }

current = 1

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

menu_setup(option, 1, 3)
menu_controls(1, 3)

screen.flip()
screen.waitVblankStart()

oldpad = pad

end

ok here is the code in a file that will just run it will display the amount of items chosen by the user maximum and move the menu up one every time down is pressed and up one every time up is pressed if you wanted the menu to come from the bottom of the screen then you would just reverse the the y code

white = Color.new(255,255,255)
red = Color.new(255,0,0)

option = { "s1", "s2", "s3", "s4", "s5", "s6", "s7", "s8", "s9", "s10", "s11", "s12", "s13", "s14", "s15", "s16", "s17", "s18", "s19", "s20", "s21", "s22", "s23", "s24", "s25", "s26", "s27", "s28", "s29", "s30", "s31", "s32", "s33", "s34", "s35" }

current = 1

function menu_setup(table_name, max_index)
for i = current, max_index do
screen:print(10,10 + 10 * i - current * 10, table_name[i], white)
screen:print(10,10 + 10 * current - current * 10, table_name[current], red)
end
end

function menu_controls(min_index, max_index)
if pad:up() and oldpad:up() ~= pad:up() and current > min_index then
current = current - 1
end
if pad:down() and oldpad:down() ~= pad:down() and current < max_index then
current = current + 1
end
end

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

screen:print(10, 0, current, red)

menu_setup(option, 30)
menu_controls(1, 30)

screen.flip()
screen.waitVblankStart()

oldpad = pad

end

this could easily be modified to be a file browser by putting the_end = table.getn(System.listDir ectory()) and then changing this line

menu_setup(option, 30)

to

menu_setup(table.getn(System.listDirectory()), the_end)

and setting the rest up as a file browser so that the other controls e.g. cross go to the next directory you would do this by putting current.name

like this

if pad:cross() and oldpad:cross() ~= pad:cross() then
System.currentDirectory(option[current])
current = 1
the_end = table.getn(System.listDirectory())
end

thanks

[email protected]

p.s. i will post a more advanced menu than this soon when i modify it to automatically change the menu's position depending on the current menu item

p.p.s. turtlespwn wouldn't your code constantly check if the new value is smaller or bigger than the old one therefore using the same amount of cpu maybe even more than mine, if not could you please explain why

[TurtlesPwn]

each loop to draw the bar, yours does this:
-declare three colors
-create a table, put System.getBatteryLifePerc ent() into it
-3 screen:fillRect()s
-11 screen:drawLine()s
-a screen print
-lots of math among all of that

each loop, mine does this:
-1 screen:blit()
-update the battery percentage value
-check if the battery charge percentage has changed enough to affect the size of the bar
------if so redraw the battery bar

And, all but the first part of mine needn't even be done every loop. If you want, you could run them every 3600 loops - once per minute (about the time it takes to charge 1% during the fast charge stage (pre-80% charge))

Trust me, if you want, I'll make a speed comparison test and the results will show that mine is SIGNIFICANTLY faster than yours.

Also, if you want a true SUPER SIMPLE menu, make each option able to be given a function to execute when X is pressed with it chosen, and turn the entire thing into about 15 lines. Yes, it is possible.

edit: also, your filebrowser modification guide will not work. System.listDirectory returns in a much different way than you seem to be using it. You set current to a number and then use current.name as a string when current is a table index. You also attempt to use System.currentDirectory without checking that the selected item is actually a directory.

[FaT3oYCG]

each loop to draw the bar, yours does this:
-declare three colors
-create a table, put System.getBatteryLifePerc ent() into it
-3 screen:fillRect()s
-11 screen:drawLine()s
-a screen print
-lots of math among all of that

each loop, mine does this:
-1 screen:blit()
-update the battery percentage value
-check if the battery charge percentage has changed enough to affect the size of the bar
------if so redraw the battery bar

And, all but the first part of mine needn't even be done every loop. If you want, you could run them every 3600 loops - once per minute (about the time it takes to charge 1% during the fast charge stage (pre-80% charge))

Trust me, if you want, I'll make a speed comparison test and the results will show that mine is SIGNIFICANTLY faster than yours.

Also, if you want a true SUPER SIMPLE menu, make each option able to be given a function to execute when X is pressed with it chosen, and turn the entire thing into about 15 lines. Yes, it is possible.

edit: also, your file browser modification guide will not work. System.listDirectory returns in a much different way than you seem to be using it. You set current to a number and then use current.name as a string when current is a table index. You also attempt to use System.currentDirectory without checking that the selected item is actually a directory.

- i wasn't having a go at you i just wanted to know why yours was faster
- where did i use System.listDirectory() ?
- current is the number, current is the numbers name in the table - the table is the memory stick directory - sorry my bad i have fixed it now i was wrong
- i dont need to check if it is a directory - i have made a file browser but i didn't check if it was a dir or not and it worked fine i think that it is if it is a file it has an extension so doesn't open it if it doesn't have an extension then it opens it as a new directory

- i didn't complete the code to make it a file browser it was just a suggestion

- also i could have made a simpler charge bar but i was going for aesthetics not speed - which doesn't really matter in lua player any way



EDIT:

a while ago now i took a look at sg57's lua state snippet but since then i have improved it and added some more functions in that are very useful here it is

white = Color.new(255, 255, 255)
black = Color.new(0, 0, 0)
red = Color.new(255, 0, 0)
green = Color.new(0, 255, 0)
blue = Color.new(0, 0, 255)
orange = Color.new(235, 115, 0)
yellow = Color.new(255, 255, 0)

state = { loading = 1, menu = 2, game = 3 }

current_state = state.loading

function Set_State(state_to_change_to)
current_state = state_to_change_to
end

function Get_State()
return current_state
end

function Start_States()
if Get_State() == state.loading then
-- do loading stuff
screen:print(10, 10, "loading state", white)
if pad:cross() and oldpad:cross() ~= pad:cross() then
Set_State(state.menu)
end
elseif Get_State() == state.menu then
-- do menu stuff
screen:print(10, 10, "menu state", white)
if pad:cross() and oldpad:cross() ~= pad:cross() then
Set_State(state.game)
end
elseif Get_State() == state.game then
-- do game stuff
screen:print(10, 10, "game state", white)
if pad:cross() and oldpad:cross() ~= pad:cross() then
Set_State(state.loading)
end
end
end

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

-- main

Start_States()

-- main

if Controls.read():start() then
break
end

screen.flip()
screen.waitVblankStart()

oldpad = pad

end

[TurtlesPwn]

"- where did i use System.listDirectory() ?"
When you set values based on table.getn(System.current Directory()), you should have been using it. currentDirectory returns a string of the current working directory that you're navigated to, not a table of the files in the current directory.
"- i dont need to check if it is a directory - i have made a file browser but i didn't check if it was a dir or not and it worked fine i think that it is if it is a file it has an extension so doesn't open it if it doesn't have an extension then it opens it as a new directory"
I don't think you've run it before - half your code for this one is broken. If you tried to cd to a file, I'm fairly certain it would get an error because it cannot find the folder. Lua isn't smart enough to check if something has an extension, and folder names can be named as if they have an extension anyways just as files can be named as if they don't.
"- i didn't complete the code to make it a file browser it was just a suggestion"
I know, but if you're going to walk people through how to do it, at least make sure your code will work - it is IMPOSSIBLE to make a filebrowser without System.listDirectory and you have it NOWHERE in your code.
"- also i could have made a simpler charge bar but i was going for aesthetics not speed - which doesn't really matter in lua player any way"
Speed doesn't matter in lua? Speed (or, code efficiency) is the most important thing in lua - lua being a fourth level language and using the slow graphics.h libraries and other restraints slowing it down, you MUST code as efficiently as possible, and you cannot let background things like a battery bar be slowing down your program. Besides, I could make my chargebar have the same aesthetics as yours while still being just as efficient as my current one.

[FaT3oYCG]

ok ill change it to System.listDirectory() - i just looked at my code again i must have read it wrong

- i dont know why the direcory thing works but i get no error

here is the dir code - which is much the same as tacticalpenguins as i used his code to understand how file browsers work

if
pad:cross() and oldpad:cross() ~= pad:cross()
then
System.currentDirectory(listitem[current].name)
current = 1
listitem = System.listDirectory()
number = table.getn(listitem)
end

- and here is the file code

if
pad:cross() and listitem[current].directory == false
then
if
string.sub(listitem[current].name, -4) == ".lua"
then
screen:clear()
dofile(listitem[current].name)
end
end

and that works fine no errors

- i did not know that lua player was that inefficient but i will think about the way i code now thanks

- i dont like starting arguments and i wasn't trying too but on the Internet the way you word a reply decides the mood or tone that the reader thinks it was in when i reply to messages it tends too look like i am having a go at people but im not trying to sorry

thanks

[email protected]

p.s. woooooooooo this was my 777'th post lol

here is a simple script that will help you to understand how draw line works it also helps for when you are trying to see from perspective

screenie:

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

x = 20
y = 20
x1 = 10
y1 = 10
gap = 20
block = Image.createEmpty(gap * 2, gap * 2)
block:clear(white)

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

-- insert your main code here

screen:print(10, 10, x .. " " .. y, white)

screen:blit(x - gap, y - gap, block)

screen:drawLine(0, 0, x - gap, y - gap, white)
screen:drawLine(480, 0, x + gap, y - gap, white)
screen:drawLine(0, 272, x - gap, y + gap, white)
screen:drawLine(480, 272, x + gap, y + gap, white)

if pad:left() then
x = x - 5
end
if pad:right() then
x = x + 5
end
if pad:up() then
y = y - 5
end
if pad:down() then
y = y + 5
end
if pad:square() then
x1 = x1 - 5
end
if pad:circle() then
x1 = x1 + 5
end
if pad:triangle() then
y1 = y1 - 5
end
if pad:cross() then
y1 = y1 + 5
end

if pad:l() then
screen:save("C:\\sc.png")
end

-- insert your main code here

if Controls.read():start() then
	break
end

oldpad = pad

screen.flip()
screen.waitVblankStart()

end

[TurtlesPwn]

ok ill change it to System.listDirectory() - i just looked at my code again i must have read it wrong

- i dont know why the direcory thing works but i get no error

here is the dir code - which is much the same as tacticalpenguins as i used his code to understand how file browsers work

if
pad:cross() and oldpad:cross() ~= pad:cross()
then
System.currentDirectory(listitem[current].name)
current = 1
listitem = System.listDirectory()
number = table.getn(listitem)
end

- and here is the file code

if
pad:cross() and listitem[current].directory == false
then
if
string.sub(listitem[current].name, -4) == ".lua"
then
screen:clear()
dofile(listitem[current].name)
end
end

and that works fine no errors

It's really bad when you can't even make stolen code work. If you're going to try to only take bits and pieces (of which there are like, 3 in a filebrowser) then at least learn to make it still work when you're done butchering it. What you've done is just as bad as stealing the whole thing and passing it off as your own. How could you have read it wrong while saying it works fine? Your code that you repeatedly insist works fine will not work.

- i did not know that lua player was that inefficient but i will think about the way i code now thanks

Luaplayer itself isn't inefficient, it's people who code like you do and use up all the cpu power in the world for the smallest little things that make it appear that way. You just have to make your code actually do as little as possible to do what you want. You obviously have never made a decent project that needs all the CPU it can get - a battery bar like yours would kill everything.

Also, your drawLine example could be cleaned up and simplified a lot:

white = Color.new(255, 255, 255)
x = 0
y = 0
bs = 10
b = Image.createEmpty(bs,bs)

while true do
	pad = Controls.read()
	screen:clear(white)
	screen:blit(x,y,b)

	screen:drawLine(0,0,x,y)
	screen:drawLine(479,0,x+bs,y)
	screen:drawLine(0,271,x,y+bs)
	screen:drawLine(479,271,x+bs,y+bs)

	ax = pad:analogX()
	ay = pad:analogY()
	if math.abs(ax) > 24 then
		x = x + ax/32
	end
	if math.abs(ay) > 24 then
		y = y + ay/32
	end

	if pad:start() then break end
	screen.flip()
	screen.waitVblankStart()
end

[Anti-QuickJay]

TurtlesPwn sure does Pwn alot.

[FaT3oYCG]

file operations

i hadnt really looked into file operations much before but after looking at how Nielkie used binary file io i have come up with some custom commands that you might find useful

- i will post them on the snippets thread too so they can bee looked at and found easily

ok there are two files or sections that you need

if you use separate files, which i like to do to keep the main file clean, but i usually just have a functions.lua file or something alike, then this would be your file operations.lua or whatever you want to call it

function file_io_reset(operand)
if operand == nil then
end
if operand == 1 then
source_file = ""
elseif operand == 2 then
output_file = ""
elseif operand == 3 then
source_file = ""
output_file = ""
elseif operand == 4 then
file_io_data_store = ""
end
end

function file_io(source_io_file, output_io_file, mode)
if mode == nil then
end
if mode == "cut" then
source_file = io.open(source_io_file, "rb")
file_io_data_store = source_file:read("*a")
source_file:close()
System.removeFile(source_io_file)
file_io_reset(1)
elseif mode == "paste" then
output_file = io.open(output_io_file, "wb")
output_file:write(file_io_data_store)
output_file:close()
file_io_reset(4)
file_io_reset(2)
elseif mode == "copy" then
source_file = io.open(source_io_file, "rb")
file_io_data_store = source_file:read("*a")
source_file:close()
output_file = io.open(output_io_file, "wb")
output_file:write(file_io_data_store)
output_file:close()
file_io_reset(4)
file_io_reset(3)
end
end

that basically just holds all of the commands for the file io that i have made

- if you just keep it in your main file then put it above while true do

ok now this would be your main file if you referenced to the file io commands file

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

dofile("./file_operations.lua")

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

-- insert your main code here

if pad:cross() and not oldpad:cross() then
file_io("./a.png", nil, "cut")
end

if pad:circle() and not oldpad:circle() then
file_io(nil, "./b.png", "paste")
end

if pad:square() and not oldpad:square() then
file_io("./b.png", "./a.png", "copy")
file_io("./b.png", nil, "cut")
end

-- insert your main code here

if Controls.read():start() then
	break
end

oldpad = pad

screen.flip()
screen.waitVblankStart()

end

that is a quick example that works with any type of file i just used an image named a.png to test it

i have only made copy, cut, and paste commands but that is all you need as moving a file would just be cut and paste at the same time, if you want to delete a file, just cut it, if you then cut another file that files data will take its place

it can only obviously cut and paste certain sized files as there is limited memory in lua player

- these functions could be optimized if you feel like it you could optimize them yourself and post it or just keep it to yourself, i just thought i would post these here for reference

[Deathinnate]

white = Color.new(255,255,255)
counter = Timer.new()
counter:start()
while true do
screen:clear()
currentTime = counter:time()
screen:print(10,10,"Counter Time: " .. currentTime,white)
if currentTime < 1000 then
screen:print(100,100,"Less than 1000",white)
end
if currentTime > 1000 and currentTime < 2000 then
screen:print(100,100,"Greater than 1000",white)
end
if currentTime > 2000 then
counter:reset(0)
counter:start()
end
screen.waitVblankStart()
screen.flip() end

Creates a little counter and says if the number is above or below 1000.

[SG57]

Here's a visualizer I found on my PSP I wrote a long time ago. It can create the Window's screensaver Lines among many other neat visualizations.

It's very readable, efficient and easily configurable. Mess with the constants for some pretty neat effects :o

-- General Constants
Screen = { leftBound = 0,    topBound = 0,
           rightBound = 480, bottomBound = 272 }

BACKGROUND_COLOR = Color.new(0,0,0) -- black bg

-- Line specific constants
NUM_LINES = 5
NUM_LINES_PER_LINE = 5

COLORS = {} -- manage respectively to match NUM_LINES
COLORS[1] = Color.new(255,255,255)
COLORS[2] = Color.new(255,0,0)
COLORS[3] = Color.new(0,255,0)
COLORS[4] = Color.new(0,0,255)
COLORS[5] = Color.new(0,255,255)

SPEEDS = {} -- manage respectively to match NUM_LINES
SPEEDS[1] = 2
SPEEDS[2] = 4
SPEEDS[3] = 6
SPEEDS[4] = 3
SPEEDS[5] = 5

-- General declarations and initiation(s)
bPaused = false

-- Line specific declarations and initiation(s)
Line = {}
for i = 1, NUM_LINES do
  Line[i] = { x = {}, y = {}, xspeed = {}, yspeed = {}, color = COLORS[i] }
  
  for j = 1, NUM_LINES_PER_LINE do
    Line[i].x[j] = math.random(Screen.leftBound,Screen.rightBound)
    Line[i].y[j] = math.random(Screen.topBound,Screen.bottomBound)
    Line[i].xspeed[j] = SPEEDS[i]
    Line[i].yspeed[j] = SPEEDS[i]
  end
end

-- All input-specific code should go in here
function Input()
  bPaused = Controls.read():cross() -- hold X to freeze the visualizer
end

-- All thinking-specific code should go in here
function UpdateLine(i)
  for j = 1, NUM_LINES_PER_LINE do
    if (Line[i].x[j] >= Screen.rightBound) then
      Line[i].xspeed[j] = -SPEEDS[i]
    elseif (Line[i].x[j] <= Screen.leftBound) then
      Line[i].xspeed[j] = SPEEDS[i]
    end
    
    if (Line[i].y[j] >= Screen.bottomBound) then
      Line[i].yspeed[j] = -SPEEDS[i]
    elseif (Line[i].y[j] <= Screen.topBound) then
      Line[i].yspeed[j] = SPEEDS[i]
    end

    if not bPaused then
      Line[i].x[j] = Line[i].x[j] + Line[i].xspeed[j]
      Line[i].y[j] = Line[i].y[j] + Line[i].yspeed[j]
    end
  end
end

-- All drawing-specific code should go in here (only exception is clearing the screen each loop)
function DrawLine(i)
  for j = 1, NUM_LINES_PER_LINE do
    if j == NUM_LINES_PER_LINE then
      screen:drawLine (Line[i].x[j],   Line[i].y[j],
                       Line[i].x[1],   Line[i].y[1],
                       Line[i].color)
    else
      screen:drawLine (Line[i].x[j],   Line[i].y[j],
                       Line[i].x[j+1], Line[i].y[j+1],
                       Line[i].color)
    end
  end
end

while true do
  screen:clear(BACKGROUND_COLOR)
  
  Input()         -- input

  for i = 1, NUM_LINES do
    UpdateLine(i) -- think
    DrawLine(i)   -- draw
  end

  screen.waitVblankStart()
  screen.flip()
end

Thought someone may find it useful.

[SG57]

Oh, here's another thing i found embedded in a maze of folders in my COMMON folder :)

It doesn't really have a name (?) but it's basically particles affected by gravity with varying speeds (darker the color, slower it goes). Makes some pretty neat visualizations when the particles form a line and it waves around and wiggles.

(if your a fan of bleach - think of it like Byakuya's senbonsakura (spelling) where you can control where they go (looks like it))

The last date modified says August 2006 and, IMO, isn't structured and designed as well as it could be. It gets the job done however and is relatively easy to configure and have fun with ;) If you can see a use for it (visualizer in an mp3 player, make it a weapon (be neat :P), etc.) go for it.

width = 480
height = 272
maxCells=500

cells = {}

for i = 1, maxCells do
  cells[i] = {nr = 0, x = 0.0, y = 0.0,
         diago = 551.7100687,
         xpos = 0, ypos = 0,
         lastXpos = 0, lastYpos = 0,
         speed = 0.0, xmov = 0.0, ymov = 0.0,
         cr = 0, cg = 0, cb = 0}
end

started=false
mouseX = 240
mouseY = 272

function initCell(x,y,i)
    cells[i].nr=i
    cells[i].x=x
    cells[i].y=y
    cells[i].xpos=x
    cells[i].ypos=y
    cells[i].lastXpos=cells[i].xpos
    cells[i].lastYpos=cells[i].ypos
    while (cells[i].xmov==0 and cells[i].ymov==0) do
      cells[i].xmov=math.random(-1.0,1.0)
      cells[i].ymov=math.random(-1.0,1.0)
    end
    cells[i].speed=0.6+(i/(maxCells+0.0))*0.8
    cells[i].cr=255
    cells[i].cg=255*(cells[i].speed-0.6)/0.8
    cells[i].cb=128+127*(cells[i].speed-0.6)/0.8
end

function initialize()
  xs = 0.0
  ys = 0.0
  rx = 0.0
  ry = 0.0
  for i=1, maxCells do
    rx=width/4+math.random(-width/8,width/8)
    ry=height/4+math.random(-height/8,height/8)
    xs=width/2+rx*math.cos(6.28318*i/maxCells) -- 6.28318 is 2pi
    ys=height/2+ry*math.sin(6.28318*i/maxCells)
    initCell(xs,ys,i)
  end
end

function setup()
  initialize()
  started=true
end

function dist(x,y,x2,y2)
  return math.sqrt( math.pow((x2 - x), 2) + math.pow((y2 - y), 2) )
end

function update(i)
    d = dist(cells[i].x,cells[i].y,mouseX,mouseY)
    attrac=0.0010*(cells[i].diago-d)/cells[i].diago

    turn=false

    for i=1, 5 do
      iran=1+math.random(0,maxCells-1)
      md=math.random(1,4)
      if (dist(cells[iran].x,cells[iran].y,cells[i].x,cells[i].y)<md) then
        turn=true
        i=5
      end
    end
    if (turn) then
      cells[i].xmov=cells[i].xmov+math.random(-0.8,0.8)
      cells[i].ymov=cells[i].ymov+math.random(-0.8,0.8)
    end

    if (cells[i].x>width or cells[i].x<1) then
      cells[i].xmov=cells[i].xmov*-1
    end
    if (cells[i].y>height or cells[i].y<1) then
      cells[i].ymov=cells[i].ymov*-1
    end

    cells[i].xmov=cells[i].xmov+(mouseX-cells[i].x)*attrac
    cells[i].ymov=cells[i].ymov+(mouseY-cells[i].y)*attrac
    cells[i].xmov=cells[i].xmov+math.random(-0.02,0.02)
    cells[i].ymov=cells[i].ymov+math.random(-0.02,0.02)

    for j=1, 5 do
      if (cells[i].nr>j) then
        cells[i].xmov=cells[i].xmov+0.001*cells[cells[i].nr-j].xmov
        cells[i].ymov=cells[i].ymov+0.001*cells[cells[i].nr-j].ymov
      end
    end

    cells[i].xmov=cells[i].xmov*0.992
    cells[i].ymov=cells[i].ymov*0.992
    cells[i].x=cells[i].x+cells[i].xmov*cells[i].speed
    cells[i].y=cells[i].y+cells[i].ymov*cells[i].speed
    cells[i].xpos=cells[i].x
    cells[i].ypos=cells[i].y

    screen:drawLine(cells[i].xpos,cells[i].ypos,cells[i].lastXpos,cells[i].lastYpos, Color.new(cells[i].cr,cells[i].cg,cells[i].cb))
    cells[i].lastXpos=cells[i].xpos
    cells[i].lastYpos=cells[i].ypos
end

function draw()
  screen:clear(Color.new(0,0,0))

  if (started) then
    for i=1, maxCells do
      update(i)
    end
  end
  
  screen:drawLine(mouseX,mouseY,mouseX+5,mouseY+5,Color.new(0,255,0))
  screen:drawLine(mouseX,mouseY+5,mouseX+5,mouseY,Color.new(0,255,0))
end

function input()
  if Controls.read():cross() then
    setup()
  end
  
  if Controls.read():left() then mouseX = mouseX - 2 end
  if Controls.read():right() then mouseX = mouseX + 2 end
  if Controls.read():up() then mouseY = mouseY - 2 end
  if Controls.read():down() then mouseY = mouseY + 2 end
  
  if mouseY >= height then mouseY = height end
  if mouseY <= 0 then mouseY = 0 end
  if mouseX <= 0 then mouseX = 0 end
  if mouseX >= width then mouseX = width end
end

setup()

while true do
  input()
  draw()

  screen.waitVblankStart()
  screen.flip()
end

One really sweet visual is to gather up speed by holding the X button. Let it loose and watch as this really cool 3dimensional figure slowly forms and rotates and slowly gets smaller and disappears :)

[andyauff]

This reduces a fraction to it's simplest form. If the denominator is 1, it returns the numerator (i.e., if the fraction is 2/1, it returns 2), and if the denominator is 0 it returns undefined. It is based off of Euclid's algorithm, and thanks go to LMelior over at evilmana.com for pointing me to the following page, which describes the algorithm.
http://en.wikipedia.org/wiki/Euclidean_algorithm

function simplify(num,denom)
         num2 = num
         denom2 = denom

         while (denom ~= 0) do
               t = denom
               denom = math.fmod(num,denom)
               num = t
         end
         
         gcf = num
         
         if (denom2/gcf) ~= 1 and (denom2/gcf ~= 0) then
            simplified = (num2/gcf .. "/" .. denom2/gcf)
         elseif (denom2/gcf) == 1 then
            simplified = (num2/gcf)
         elseif (denom2/gcf) == 0 then
            simplified = "undefined"
         end
end

[FaT3oYCG]

hi another snippet here, i decided to make a scrolling marquee function for lua player, i messed around trying to make a function that would work well in many different ways but found that the best way was to print the string onto images and scroll the images from one side to the other, the function has options for the string to be used, the y position, the background colour, the text colour and the speed at which the string will cycle from one side of the screen to the other

the direction of the marquee is determined by the speed if it is positive then the marquee will scroll from left to right if it is negative it will scroll from right to left, before circulating again

- i found that a nice quick speed where the text is still readable is 1.2 and -1.2, and a good slow scrolling speed is 0.5 and -0.5, but that is just my opinion

- i wouldn't choose speeds such as 20 as the letters and words will become unreadable

- this code may be unefficient but it works perfectly with a small amount of calculations

ok here is the code - this code will run if put into an lua file and played with either windows or psp lua player versions, without any modification

white = Color.new(255, 255, 255)
black = Color.new(0, 0, 0)

xpos = 0

function scrolling_marquee(marquee_string, y_position, background_colour, text_colour, speed)

xpos = xpos + speed

string_len = (string.len(marquee_string) * 8)

images_needed = math.ceil(string_len / 64)
for i = 1, images_needed do
text_image = {  }
text_image[i] = Image.createEmpty(512, 10)
text_image[i]:clear(background_colour)
marquee_string_part = string.sub(marquee_string, (64 * i) - 64, 64 * i)
text_image[i]:print(0, 1, marquee_string_part, text_colour)
screen:blit(xpos + (512 * i) - 512, y_position, text_image[i])
end

if speed > 0 then
if xpos > 480 then
xpos = 0 - (string_len)
end
elseif speed < 0 then
if xpos < (0 - string_len) then
xpos = 480
end
end

end

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

-- insert your main code here

scrolling_marquee("test string for marquee and it is a really long string so it will go off the end of the screen but i am going to test it with lots of images as it will be quick and also it will create the right amount of images for the strings length which is an added bonus so the string can be as long as you want it to be", black, white, 1.2)

-- insert your main code here

if Controls.read():start() then
	break
end

oldpad = pad

screen.flip()
screen.waitVblankStart()

end

thanks

[email protected]

p.s. thanks to eldiablov for suggesting to use images

[FaT3oYCG]

resize image function

this function resizes an image to the maximum size that you set, if you want the image to be smaller than 100 width or height and you dont know which is bigger on the image it wont matter it works it out for you

how it woks
you input the image you want to use and the maximum size
it then works out weather the height or width is larger
it then takes an aspect ratio based on that
it then makes the larger size width or height the maximum size you requested
it then makes the other width or height relevant to that based on the aspect ratio

usage

my_resized_image = resize_image(Image.load("picture.png", 200)

screen:blit(10, 10, my_resized_image)

the code

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

function resize_image(the_image, max_size)

image_height = the_image:height()
image_width = the_image:width()

	if image_height ~= max_size or image_width ~= max_size then

		if image_width > image_height then
			resize_type = width
			image_aspect = (image_width / image_height)
		elseif image_width < image_height then
			resize_type = height
			image_aspect = (image_height / image_width)
		elseif image_width == image_height then
			resize_type = width
			image_aspect = (image_width / image_height)
		end

		if resize_type == width then
			new_image_width = max_size
			new_image_height = max_size / image_aspect
		elseif resize_type == height then
			new_image_height = max_size
			new_image_width = max_size / image_aspect
		end

	scaled_image = Image.createEmpty(new_image_width, new_image_height)

		for x = 1, new_image_width do
			for y = 1, new_image_height do
				scaled_image:blit(x,y , the_image, math.floor(x*(the_image:width()/new_image_width)), math.floor(y*(the_image:height()/new_image_height)),1,1)
			end
		end

		return scaled_image
	else
		return the_image
	end
end

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear()

-- insert your main code here

an_image = resize_image(Image.load("picture.png"), 100)

screen:print(10, 10, an_image:width(), white)
screen:print(10, 20, an_image:height(), white)
screen:blit(10, 40, an_image)

-- insert your main code here

if Controls.read():start() then
	break
end

oldpad = pad

screen.flip()
screen.waitVblankStart()

end

EDIT:

i just changed this line

if image_height > max_size or image_width > max_size then

to this

if image_height ~= max_size or image_width ~= max_size then

so it can make images smaller or larger

[FaT3oYCG]

ok im here again with another sample, before anyone says no i didn't copy any of it and no i did not use any examples the only thing i had to look up was the table.remove function that i have used from the lua users wiki, other than that i spent quite a while creating the priority system, it is useful for more things than this but adding it to this is one of the main features

ok so i know now your asking what the hell has he made, well i have made ...

a windowing system, it mixes a nice looking interface with speed and control

ok so here is the code

white = Color.new(255, 255, 255)
black = Color.new(0, 0, 0)
red = Color.new(255, 0, 0)
green = Color.new(0, 255, 0)
blue = Color.new(0, 0, 255)
orange = Color.new(235, 115, 0)
yellow = Color.new(255, 255, 0)
ubuntu_brown = Color.new(220, 170, 130)

windows = { }
duplicate_window_number = 0

function create_window(window_x, window_y, window_width, window_height, window_title)
	for i = 1, table.getn(windows) do
		if windows[i].title == window_title then
			duplicate_window_number = duplicate_window_number + 1
			window_title = window_title .. " (" .. duplicate_window_number .. ")"
		end
	end
	window_number = table.getn(windows) + 1
	windows[window_number] = { x = window_x, y = window_y, width = window_width, height = window_height, title = window_title, old_width = window_width, old_height = window_height, old_x = window_x, old_y = window_y, priority = table.getn(windows) + 1, state = 1 }
	
	-- create window images
	window_outline = Image.createEmpty(windows[window_number].width, windows[window_number].height)
	window_background = Image.createEmpty(windows[window_number].width - 2, windows[window_number].height - 2)
	window_bar = Image.createEmpty(windows[window_number].width - 4, 10)
	window_main = Image.createEmpty(windows[window_number].width - 4, windows[window_number].height - 15)
	-- create window images

	-- colour window images
	window_outline:clear(black)
	window_background:clear(ubuntu_brown)
	window_bar:clear(white)
	window_main:clear(white)
	-- colour window images

	-- display window title
	window_bar:print(1, 1, windows[window_number].title, black)
	-- display window title

	-- blit window images to the main image
	window_background:blit(1, 1, window_bar)
	window_background:blit(1, 12, window_main)
	window_outline:blit(1, 1, window_background)
	-- blit window images to the main image

	-- create the window image in that windows table
	windows[window_number].image = window_outline
	-- create the window image in that windows table
end

function refresh_window(window_number)
	-- create window images
	window_outline = Image.createEmpty(windows[window_number].width, windows[window_number].height)
	window_background = Image.createEmpty(windows[window_number].width - 2, windows[window_number].height - 2)
	window_bar = Image.createEmpty(windows[window_number].width - 4, 10)
	window_main = Image.createEmpty(windows[window_number].width - 4, windows[window_number].height - 15)
	-- create window images

	-- colour window images
	window_outline:clear(black)
	window_background:clear(ubuntu_brown)
	window_bar:clear(white)
	window_main:clear(white)
	-- colour window images

	-- display window title
	window_bar:print(1, 1, windows[window_number].title, black)
	-- display window title

	-- blit window images to the main image
	window_background:blit(1, 1, window_bar)
	window_background:blit(1, 12, window_main)
	window_outline:blit(1, 1, window_background)
	-- blit window images to the main image

	-- create the window image in that windows table
	windows[window_number].image = window_outline
	-- create the window image in that windows table
end

function display_windows()
	for i = 1, table.getn(windows) do
		if windows[i].state ~= 0 then
			screen:blit(windows[i].x, windows[i].y, windows[i].image)
		end
	end
end

function minimize_all_windows()
	for i = 1, table.getn(windows) do
		windows[i].state = 0
	end
end

function minimize_window(number)
	windows[number].state = 0
end

function maximize_window(number)
	if windows[number].state ~= 2 then
		windows[number].old_x = windows[number].x
		windows[number].old_y = windows[number].y
		windows[number].old_width = windows[number].width
		windows[number].old_height = windows[number].height
		windows[number].state = 2
		windows[number].x = 0
		windows[number].y = 20
		windows[number].width = 480
		windows[number].height = 232
		refresh_window(number)
	end
end

function restore_window(number)
	if windows[number].state ~= 1 then
		windows[number].state = 1
		windows[number].x = windows[number].old_x
		windows[number].y = windows[number].old_y
		windows[number].width = windows[number].old_width
		windows[number].height = windows[number].old_height
		refresh_window(number)
	end
end

function change_priority(window)
	temp = { }
	for i = 1, table.getn(windows) do
		temp[i] = windows[i]
	end
	windows[1] = windows[window]
	for i = 2, table.getn(windows) + 1 do
		windows[i] = { }
		windows[i] = temp[i - 1]
	end
	table.remove(windows, window + 1)
end

oldpad = Controls.read()

while true do

pad = Controls.read()

screen:clear(white)

-- insert your main code here

if pad:cross() and not oldpad:cross() then
	create_window(10, 10, 300, 200, "title")
end

display_windows()

if pad:up() then
	windows[table.getn(windows)].y = windows[table.getn(windows)].y - 3
elseif pad:down() then
	windows[table.getn(windows)].y = windows[table.getn(windows)].y + 3
elseif pad:left() then
	windows[table.getn(windows)].x = windows[table.getn(windows)].x - 3
elseif pad:right() then
	windows[table.getn(windows)].x = windows[table.getn(windows)].x + 3
end

if pad:triangle() and not oldpad:triangle() then
	change_priority(table.getn(windows))
end

-- insert your main code here

if Controls.read():start() then
	break
end

oldpad = pad

screen.flip()
screen.waitVblankStart()

end

yeah there is a lot, i added lots of functions so you can play around with them if you like, if you know what one of my main current projects is then you will understand the reason why i made this

now this took quite a while to make and i had to do a lot of recoding to get things to work so i would greatly appreciate that you credit me if you use this

-- functions
create_window() creates a window, the arguments are x position, y position, width, hight, and the title for that window
refresh_window() clears the window of all data inside the main box, the argument is the window to refresh
display_windows() does what it says and displays all of the windows if their state is right
minimize_all_windows() sets all of the windows states to 0 so that they are all minimized in effect
minimize_window() minimizes the window selected, the argument is the number of the window to minimize
maximize_window() makes the window full screen, the argument is the window to maximize
restore_window() makes the window return to the size it was before minimized or maximized

-- putting data in a window

to put data in a window use this method

window[number].image:print(3, 18, "data")

- i will make a function to do this so it is easier to use


thanks

[email protected]

- p.s. works on lua player windows

- p.s.s adding explanations of the functions and how to put data in a window

- p.s.s.s i reserve the right to change or add to this code at any time

[ifiwere1337]

someone needs to update the first post so that it is easier to find the scripts, i had to look through about 8 pages to find the script that i couldnt think of the name or what it did, but i knew it would help me

[TurtlesPwn]

set pagination to 50
ctrl+f

[SG57]

ifiwere1337 - Everyone knows to set the posts p/page to 40 (i believe that's the max) then use any find-feature in your browser...

[FaT3oYCG]

ifiwere1337 - Everyone knows to set the posts p/page to 40 (i believe that's the max) then use any find-feature in your browser...

yeah if you do that then you get about 4 pages for this thread in total - to make sure i get the max i chose custom and put 99 but it doesn't actually show 99 ppp

[ifiwere1337]

ifiwere1337 - Everyone knows to set the posts p/page to 40 (i believe that's the max) then use any find-feature in your browser...

the thing is that i forgot what it was called or what it did, but i knew i could use it, so i couldnt search for it, where is the ppp setting?

[FaT3oYCG]

in user cp under options i think

EDIT:

here

user cp

- edit options

-- thread display options

--- Number of Posts to Show Per Page

[ifiwere1337]

in user cp under options i think

EDIT:

here

user cp

- edit options

-- thread display options

--- Number of Posts to Show Per Page

thanks nowi got it

[PSProgramer]

no one posts here any more it's been almost a month since anyone added anything to the thread

[TurtlesPwn]

so? people are tired of handing out their code that they WORKED to create to noobs who copy and paste it and complain when it doesn't work.

[PSProgramer]

Hey!! I wasn't saying people had to just hand out there code, don't get so defensive, I was just noticeing, how this thread isn't being used, and so there should be a thread here that isused, instead. I wasn't saying that I want to take anyones, code or anything. I don't steal code like that and call it my own!!

[michaelp]

There's already 8 pages (20 post per page) of post, and the first post is absolutely massive, don't you think that's enough to learn from?