Bit of help

[Hass]

Ok, so I'm pretty much a newbie at this, and was taking some time to try and get things working. I've coded with BASIC before, and a lot of the ideas were obviously familiar to me. However, I got my program working on my DS, managing to load the background, and using the touch screen functions. However, when i added something, it caused me to get only a black screen and nothing else. When I tried the backup copy I'd save before I made any adjustments, I also got the black screen. Any help? The code is below, and I'm using a CycloDS Evolution card. If there is simply an error in the code, that'd be nice to know too. As I say, all I get is a black screen, although it was previously working fine.

SCREEN_BOTTOM = 0
SCREEN_TOP = 1
BGTopText = Screen.LoadTextBG() Screen.Initialize( SCREEN_TOP, BGTopText )
BGBotMap = Screen.LoadTileBG()
BGBotMap:LoadPalette( "background.pal" )
BGBotMap:LoadTiles( "background.raw", 256 ) -- 256 colours
BGBotMap:LoadMap( "background.map", (256 / 8 ), ( 192 / 8 ) )
Screen.Initialize( SCREEN_BOTTOM, BGBotMap )

BGTopText:PrintXY( 10, 10, "Crime Scene Alpha" )

-- Main code below


while Pads.Start() == false do
if Stylus.Down() then
          touchscreenpressed = true
          stylusx = Stylus.X()
          stylusy = Stylus.Y()
          styluslifted = false
else
          if touchscreenpressed then
                    styluslifted = true
          end
          touchscreenpressed = false
end

if styluslifted then
   if stylusx >= 193 and stylusx <= 215 and stylusy <= 101 and stylusy >= 60 then
        BGTopText:PrintXY( 1, 1, "Hmm, a bottle." )
       
end

[Jryvn]

This may help.

1.  line 3 should be split up into two lines, between LoadTextBG() and Screen.Initialize

2. you need end statements for every  if/then/else statement and the while loop even if it just contains one statement in between.

[Jeremysr]

I don't see any problem other than the missing end statements like Jryvn said. It should probably show an error if that's wrong (I'm not 100% sure it's wrong, but I'm.. pretty sure). Maybe try it in different versions of DSLua (0.6 and 0.7) to see if it's a problem with DSLua. DSLua 0.7 has quite a few bugs actually. (The next version should be much better by the way.)

1.  line 3 should be split up into two lines, between LoadTextBG() and Screen.Initialize

Line breaks don't do anything in DSLua, you could have an entire program written on one line with just spaces seperating the "lines" of code. That's why I use lines like "while not Pads.A() do end".

[daltonlaffs]

That's something I'm having trouble figuring out. There's normally an error report system, but in 0.7, I think there was a compiling mistake. It shows a black screen instead of the error. That'll be fixed in the next version.

[Hass]

Ok, so its just a problem with 0.7? Or a problem with my code? If I add the end statements it should, hypothetically, work?

[Jeremysr]

It's a problem with both I think, according to daltonlaffs. 0.7 displays black screens instead of errors, and you not "end"ing your if statements is causing the "error screen". So yeah, it should work if you add end statements to all your while/if statements.

[Hass]

Aight, go it working. Next problem 

using this:

Background16Bit = Screen.Load16BitBG()  (i imagine next would go...)
Screen.Initialize( 1, Background16Bit ) (alright, but how do i then load the actual BMP image into the program?)

[Jeremysr]

First use the I/O library and load the image file into a string. Use the binary mode ("rb"). Then use one of the Image functions to copy the stored image onto the screen. By the way I think one of the image-loading functions doesn't work, but I don't remember which one.

[daltonlaffs]

They all work, but they freeze for no reason sometimes. I have no idea...