Lua Programming Help Thread

is this how i should use it?

sfond = Image.load("sfond.png")

function rotateImage(theImage, angle)
screen:blit(0,0,theImage)
angle = angle*(6 + (1/3))/360
for x = 1, theImage:width() do
for y = 1, theImage:height() do
tX = math.cos(angle)*(x-theImage:width()) - math.sin(angle) * (y-theImage:height())
tY = math.sin(angle)*(x-theImage:width()) + math.cos(angle) * (y-theImage:height())
screen:fillRect(tX + 240, tY + 136, 2, 2, screen:pixel(x, y))
end
end
end

while true do
rotateImage(sfond,360)
......... etc
i get an error line 29 wich is the screen:fillrect, an argument was incorrect

Zitat:

---

Zitat von fuxer

is this how i should use it?

sfond = Image.load("sfond.png")

function rotateImage(theImage, angle)
screen:blit(0,0,theImage)
angle = angle*(6 + (1/3))/360
for x = 1, theImage:width() do
for y = 1, theImage:height() do
tX = math.cos(angle)*(x-theImage:width()) - math.sin(angle) * (y-theImage:height())
tY = math.sin(angle)*(x-theImage:width()) + math.cos(angle) * (y-theImage:height())
screen:fillRect(tX + 240, tY + 136, 2, 2, screen:pixel(x, y))
end
end
end

while true do
rotateImage(sfond,360)
......... etc
i get an error line 29 wich is the screen:fillrect, an argument was incorrect

---

you use it like this:

Code:

---

sfond = Image.load("sfond.png")

-- Make a variable that will decide the angle--

RotateAngle = 0

function rotateImage(theImage, angle)
screen:blit(0,0,theImage)   
angle = angle*(6 + (1/3))/360
        for x = 1, theImage:width() do
                for y = 1, theImage:height() do
                        tX = math.cos(angle)*(x-theImage:width()) - math.sin(angle) * (y-theImage:height())
                        tY = math.sin(angle)*(x-theImage:width()) + math.cos(angle) * (y-theImage:height())
                        screen:fillRect(tX + 240, tY + 136, 2, 2, screen:pixel(x, y))
                end
        end
end

while true do

rotateImage(sfond, RotateAngle)

-- NOW, if you want to rotate it by 360 degrees do:
RotateAngle = 360

screen.waitVblankStart()
screen:flip()
end

---

i still get an argument was incorrect in the same line
screen:fillRect(tX + 240, tY + 136, 2, 2, screen:pixel(x, y))

Zitat:

---

Zitat von fuxer

i still get an argument was incorrect in the same line
screen:fillRect(tX + 240, tY + 136, 2, 2, screen:pixel(x, y))

---

post your image

Good luck, even after you get the function down, your FPS will drop dramatically when used.

one: where can i find a quick, easy, and free program that will let me make transparent .pngs? i don't have paintshop pro or photoshop.



http://i5.tinypic.com/20qg77o.jpg
^^
That's a screenshot of Orbs for PC, a game my friend and I made using Gamemaker which has a very easy level editor. In lua though, there is basically no way to make a level without defining each and every solid object's x and y which can be very frustrating. hese's my proposal:

two: is there a way I can take a tilemap of the image above

Code:

---

--Map

mapSource =
(
"T                            T"
"T K                    TTTTTT"
"T                      B    T"
"T                      B    T"
"T                      B    T"
"T BB                    B    T"
"T                      TTTTTT"
"T                            T"
"T                            T"
"T                            T"
"T    BB          TT        T"
"T                            T"
"T                            T"
"T          TT              T"
"T                            T"
"T                            T"
"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"
)

--see the resemblence?

---

and get its info to draw a different 16x16 image at each place, except where there is a space. you see 480/16=30 so i have 30 characters across and i do the same with 272/16 and get 17 vertically. F=floor, T=tiki-looking tile, B=blue tile and still be able to use

Code:

---

function collision(x1, y1, w1, h1, x2, y2, w2, h2)
        if (y2 >= y1 and y1 + h1 >= y2) or (y2 + h2 >= y1 and y1 + h1 >= y2 + h2) or (y1 >= y2 and y2 + h2 >= y1) or (y1 + h1 >= y2 and y2 + h2 >= y1 + h1) then
                if x2 >= x1 and x1 + w1 >= x2 then
                return true
                elseif x2 + w2 >= x1 and x1 + w1 >= x2 + w2 then
                return true
                elseif x1 >= x2 and x2 + w2 >= x1 then
                return true
                elseif x1 + w1 >= x2 and x2 + w2 >= x1 + w1 then
                return true
                end
        end

return false
end

---

^That for collision detection for my main player object? and if i touch the K block (a key) all the B blocks disappear?

please help!?!


ps: and i don't want all the BKFT images to be in the same image, well they don't have to be anyway.

Mako:
gimp.org
GIMP is free and legal.

I'm terrible, so I can't really help with anything else.

thanks Aphonia i'll try it. as for level design.... i was thinking of making something like:

look at Mapsource, read 1st line, if at 1st position of 1st line (0,0) there is a T make object TikiX[0] and TikiY[0]=(x and y of the grid)*16, and then check the next grid section all the way to section (29,0), then go on to (0,1) all the way to (29,1) and so on untill i have set all the different objects. then I'd blit the image at TikiX and TikiY, and hopefully it would do it to TikiX(0-46) , bacause there are 46 'T's in my level grid. so if i wanted to set the blue block at grid position (2,5) i'd make the BlueX[3](because it's the 4th blue block found in the grid)=2*16 and BlueY[3]=5*16. but how would I make the code sort this without me having to define every single TikiX[0-46] ? and if i told it

Code:

---

Image:blit(TikiX, TikiY, sprTiki,  false)

---

would it blit it to every single tikiX[0-46] and TikiY[0-46] ? or just the 1st one?



help! ive been programming Lua for 2 days now and the only thing keeping me alive is my knowledge of Gamemaker and how that code function works.

have you checked this tutorial? It explains how to make a tilebased map:

http://wiki.ps2dev.org/psp:lua_player:tutorial

yeah i have tried that tuturial, but that tuturial works on grid based movement, not dynamic movement, like mine. if you play the tutorial, it looks very bumpy, and each tile doesn't have an X and Y that I can use for collision detection. you get me? maybe I should post my game and see what you guys think