Lua Programming Help Thread

[myschoo]

can anyone tell me how to draw circle?

[emericaska8r]

yes, this came up a while back:

function drawCirc(where, x, y, radius, color)

	theta = 0

	while theta<=360 do
		where:drawLine((math.sin(    theta)*radius)+x, (math.cos(theta)*radius)+    y, (math.sin(theta+1)*radius    )+x, (math.cos(theta+1)*radius    )+y, color)
		theta = theta+1
	end
end

[youresam]

yes, this came up a while back:

function drawCirc(where, x, y, radius, color)

	theta = 0

	while theta<=360 do
		where:drawLine((math.sin(    theta)*radius)+x, (math.cos(theta)*radius)+    y, (math.sin(theta+1)*radius    )+x, (math.cos(theta+1)*radius    )+y, color)
		theta = theta+1
	end
end

Sigh..idiot...sin and cos are in RADIANS not DEGREES.

[Bob Hoil]

I have tryed a few things for the battery then searched for some tutorials but didn't find anything anyone know of a tutorial?

[psp phd]

What are the number codes for wait time with

screen.waitVblankStart()

Sorry for such a n00b question, but I'm just getting into all this. :)
Thanks in advance for the kind help.

[youresam]

I have tryed a few things for the battery then searched for some tutorials but didn't find anything anyone know of a tutorial?

Yeah, I found a great one before: http://www.ies.co.jp/math/java/samples/sinBox.html

[SG57]

youresam - Not everyone is a know-it-all like you.

Bob Hoil - 'for the battery' means what? Get its voltage, its temperature, its battery life in time, battery life in percent, etc.

[youresam]

youresam - Not everyone is a know-it-all like you.

Its called using sine.

[emericaska8r]

youresam - Not everyone is a know-it-all like you.

thanks :Punk:

[psp phd]

Anyone care to help me with my question?

[emericaska8r]

What are the number codes for wait time with

screen.waitVblankStart()

Sorry for such a n00b question, but I'm just getting into all this. :)
Thanks in advance for the kind help.

let me see, i'm not completely sure what you mean, but the numbers you can put in the screen.waitVblankStart() will tell the psp how much milliseconds to wait.

[youresam]

let me see, i'm not completely sure what you mean, but the numbers you can put in the screen.waitVblankStart() will tell the psp how much milliseconds to wait.

No, thats System.sleep().
screen.waitVblankStart() is 1/60 of a second, and Shine added a parameter to run that function x times.

[LMelior]

It said line 54 and...that was line 54 o.o

pad = Controls.read()

I get an error "Attempt to index global 'controls' (a nil value)"


This tells me differently. A capital C is correct, and the error was from having a lowercase c.

let me see, i'm not completely sure what you mean, but the numbers you can put in the screen.waitVblankStart() will tell the psp how much milliseconds to wait.

Not quite... screen.waitVblankStart(60 ) is one second. The command means something like "wait for vertical sync" or something (not sure about the exact terminology), which occurs 60 times per second on the PSP (60 Hz). I just know the screen can only update once every 1/60th of a second.

EDIT: youresam beat me to it, but I added more info.

[youresam]

The command means something like "wait for vertical sync" or something (not sure about the exact terminology), which occurs 60 times per second on the PSP (60 Hz).

Its an old term from CRTs that would wait for the next vertical blank before redrawing to the screen.

I just know the screen can only update once every 1/60th of a second.

With screen.waitVblankStart(), yes. But without it, I've pulled off 1500 frames per second (no thats not a typo) with luaplayer.

[yumCOOKIEZZ]

O noes. I new error =(

Image.load: Error loading image.



Any help?

[Urameshi]

you didnt load the image right

[Bob Hoil]

I meant i want to make one that looks like the one on the xmb. I want the battery shape. Thanks BobHoil

[psp phd]

Thanks for the help guys. I work full time, but have been working on Lua as a hobby. :)
(I've been on the PSP scene almost since the start.)
This is very exciting. I'll see you guys around the forums :)

[Anti-QuickJay]

Its an old term from CRTs that would wait for the next vertical blank before redrawing to the screen.


With screen.waitVblankStart(), yes. But without it, I've pulled off 1500 frames per second (no thats not a typo) with luaplayer.

Wow.

Anyways, Would you be able to edit lua player to allow a 1080x1080 picture to be loaded and blited to screen without taking all the memory? Or will memory be a issue?

[yumCOOKIEZZ]

you didnt load the image right

but what isn't right about it?

logo = Image.load("Images/logo.jpg")

I have logo.jpg stored in the Images folder.

[Urameshi]

logo=Image.load("./Images/logo.jpg")

[yumCOOKIEZZ]

Same Error =(

I'm gonna try it with a different image and see what happens.

[Urameshi]

why dont you just post your code?

[yumCOOKIEZZ]

I tried a different image and it worked.

Does size have anything to do with image loading? It isn't a big picture but when I switched to the 'Powered by Lua' image it worked fine.

I guess Lua just doesn't like the windows vista logo.

[emericaska8r]

No, thats System.sleep().
screen.waitVblankStart() is 1/60 of a second, and Shine added a parameter to run that function x times.

whoops :Argh:

[Urameshi]

well i know that the picture cant be like over 500x500

[yumCOOKIEZZ]

How do I make an image appear transparent? I want one image on top on another but I don't want all of the white around it.

[emericaska8r]

change the alpha value of the image. (0 being clear, 255 being opaque)

[ahrimanes]

hii there people...
i have to ask..
is there a way to blit a lightblend image... if soo how ?
is there a way to texture lightblend in gu ... is soo how ?
thanks in advance.

[youresam]

hii there people...
i have to ask..
is there a way to blit a lightblend image... if soo how ?
is there a way to texture lightblend in gu ... is soo how ?
thanks in advance.

No.
Set the texture mode to Gu.TFX_MODULATE, it basically caps the colors at the defined RGBA color. (So for 100 transparency do Color.new(255,255,255,100 ))
-= Double Post =-

I tried a different image and it worked.

Does size have anything to do with image loading? It isn't a big picture but when I switched to the 'Powered by Lua' image it worked fine.

I guess Lua just doesn't like the windows vista logo.

Yeah, thats probably it.