C/C++ Programming Help Thread

Zitat:

---

Zitat von Auraomega

Not quite programming, but I need some help on decrypting the pspbtcnf.bin file from the m33 firmwares, don't know where or whom to ask, so if anyone can point me in the right direction I'd apprechiate it.

-Aura

---

Don't know if you found what you're looking for but look for PSPBT Edit by Zinga Burga (or dl from attached). I think it's what you're looking for: edit the .bin files from 3.5X M33 yea? Well it edits them and he included source code which may help you understand how to decrypt them (look in modMain.bas)


also just a quick question:

The difference between for(;;) and while(1)

It's my understanding that when you use for(;;) it makes the program constantly check the conditions and operations for the "for" every loop i.e. for(conditions 1; conditions 2; operations 3), whereas using a "while" loop makes the program only check the one condition i.e. while(condition).

My question is this: in a large program, could using several for(;;) prove slower than using the while(1)?

I've always used "while" or "do.. while" for my programming but have been seeing a lot of for(;;) lately. Just curious what is the standard practice and which has better performance?

Ah, thanks for that I hadn't solved it, was looking at alternative ways but this will certainly prove easier.

for(;;) is quicker than while(1) with some compilers, and the same speed in others... we had a little convo a few pages back about this, might interest you to take a look back :p

-Aura

yeah i saw that it was like two posts i was trying to understand more in depth what makes one "unnoticeably" faster. Maybe i'll write up a simple test that will spawn 1000 threads each containing a for(;;) loop and then another test that spawns them using the while(1) loop.

The only reason I would think the "for" loop may be unconventional is because with the while loop you can do things like

while (!exiting) {
... do stuff
}

and to exit the loop you can just set "exiting = 1"
with the "for" loop, how exactly would it work? like this?

for (;!exiting;) {
... do stuff
}

ty for input

I think, and only think so I'm probably wrong, but it may be because with the for loop, if there is nothing in the first bit maybe it just doesn't bother reading the others, no idea really.

I guess for exiting you could do something like:

Code:

---

for (;;) {
... do stuff
if(exiting) break;
}

---

-Aura

That second one is the same thing as a while loop. You know about the break keyword, right? You'll need to do that. Anyway, in a for loop, there is only one condition
for(do_first;check_every; do_after_every);
If do_first is blank, presumably, the compiler puts nothing there. No instruction at all. If do_after_every is blank, presumably the compiler also puts nothing there, equating it to a while(check_every) loop. However, the difference here is that check_every in a while loop must be something, whereas in a for loop, it can be empty. Therefore, a smart C compiler will put no condition for the for loop, and just loop until it reaches a break. The while loop, however, checks every time the loop is run. Depending on the assembler language and the compiler, this may or may not be able to be done in one instruction. In MIPS, you can do this in one instruction (bgtz), but who knows how the compiler assembles it? I sure don't. Also, not all instructions take just one cycle to complete, and, I believe, some processors can do more than one instruction per cycle. I'm not a hardware guy, so I don't really know. Either way, it really boils down to which one you think you should use, or, if it's targeted to a specific system (like it is here), benchmarking to see which is faster. Either way, it will not pose a significant difference in operation time because the difference is only one or two instructions.

Archaemic ty that is exactly the answer I was looking for. In depth, but concise and clear. Thank you!

I know about the break keyword and i now understand why the "for" loop can perform faster than a while loop.

I think I am beginning to see there are several ways to skin this cat and all depend on exactly what you are trying to accomplish. While one may not necessarily perform faster than the other, it's the conditions you set and what you actually do within the loop that can affect the performance. an empty "for(;;)" loop with an "if (condition) break;" would essentially be the same as a "while (condition)" performance wise - either way the loop has a "check_every" condition, in one form or another.

Zitat:

---

Zitat von Auraomega

I get masses of errors if I add this to my makefile...

USE_PSPSDK_LIBC = 1

Change that to

USE_PSPSDK_LIBC = 0

or simply remove it, normally solves the problems.

-Aura

---

mm i dont have taht in my makefile but i believe, im missing something in my LIBS line... i got error undefined reference to fopen, fclose etc so i tried to add -lpsplibc and now im getting strange error FreeMemSize something o_O

is stdio.h one of your includes?

whenever I see "undefined reference to" there are two things I check

1) header files are included in main.c
2) LIBS are included in makefile

i.e. should have #include <stdio.h> in your main.c and -lc in your makefile (-lc includes the "libc" library which includes the io functions)

Or maybe just add "USE_PSPSDK_LIBC = 1" or "USE_KERNEL_LIBC = 1" to your makefile and not include the -lc

ofcourse...

edit hmm i finally compiled it but it doesnt work lol

Guys, the for vs while argument is moot. The compiler will optimise it out to the same instructions at O2 or O3.

Code:

---

Vertex __attribute__((aligned(16))) triangle[3] =
{
        { GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 0.0f, 1.0f, 0.0f },    // top point
        { GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 1.0f,-1.0f, 0.0f },    // left point
        { GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ),-1.0f,-1.0f, 0.0f }      // right point
};

---

in GU what are the limites on the screen , I know 0,0f is the middle of the screen but what's the max (x and y)?

It depends on how you set up the viewport...

lol you starting 3D too Hallo?

Zitat:

---

Zitat von hallo007

Code:

---

Vertex __attribute__((aligned(16))) triangle[3] =
{
        { GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 0.0f, 1.0f, 0.0f },    // top point
        { GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 1.0f,-1.0f, 0.0f },    // left point
        { GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ),-1.0f,-1.0f, 0.0f }      // right point
};

---

in GU what are the limites on the screen , I know 0,0f is the middle of the screen but what's the max (x and y)?

---

it depends on the viewport. test using a box or something. in 3d, space isnt measured in pixels, but in units.

good luck :D

According to PS2dev sources, there is a limit, for the PSP hardware at least. It has a "guard-band" of 4096x4096, so the largest coordinates are (-2048,-2048) to (2047, 2047).

If this is not enough for you, for some reason, you should probably try to scale everything smaller.

Zitat:

---

The following lines declare the buffers used for our drawings and the viewport size. The Draw buffer - where the GU will render the polygons, Display buffer is the one which is displayed on the screen and Depth buffer used to sort the polygons in order.
Don’t worry about the values yet, will be explained on a later tutorial.

---

I dint find the explanation in any of those tuts

Code:

---

        sceGuOffset( 2048 - (SCR_WIDTH/2), 2048 - (SCR_HEIGHT/2));
        sceGuViewport( 2048, 2048, SCR_WIDTH, SCR_HEIGHT);
        sceGuDepthRange( 65535, 0);

---

maximums
x = 2048.0f
y= 2048.0f
z = 65535.0f

?

Those are post-projective max/min values, so they won't help you. At least regarding depth, the pre-projective min/max is defined by your projection setup's last two parameters. So you have control of that part. The other is dependant on the objects z coordinate and your projection FOV.

Why's my post here? ;)

How would I unload a module? I've tried using this

Code:

---

    SceModule *mod;
   
    while ((mod = sceKernelFindModuleByName("scePaf_Module")))
        {
                sceKernelStopModule(mod->modid, 0, NULL, NULL, NULL);
                sceKernelUnloadModule(mod->modid);
        }

---

but for some reason my .prx refuses to load, returning the library not found error, just wondering if I've made any major mistakes?

-Aura

Is your PRX kernel mode? Because I'm fairly certain at least one of those functions is only available in kernel mode.

Ah, fair enough, its a 3.XX app currently, so I'll just move that over to the list of things to add to the KMode plugin. Cheers.

-Aura

I tried to make a texture and show it on screen , but it failed for 50% because my quad is to big

Code:

---

Vertex __attribute__((aligned(16))) vierkant[3*2] =
{
        { 0,1,GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ),-1.0f, 1.0f, 0.0f },
        { 1,1,GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 1.0f, 1.0f, 0.0f },
        { 0,0,GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ),-1.0f, 0.5f, 0.0f },
       
    { 0,0,GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ),-1.0f, 0.5f, 0.0f },
        { 1,1,GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 1.0f, 1.0f, 0.0f },       
        { 1,0,GU_COLOR( 1.0f, 1.0f, 1.0f, 0.0f ), 1.0f, 0.5f, 0.0f }

};

---

i have really no idea how i can found out with this information how big my texture has to be:s

....that's because you place it at depth = 0... by any chance, take a read on perspective projection and it's formula, then think about how big your x/y needs to be to match a specific z value and why z = 0 will never do good.

how can i clear a specific Y line on screen. for instance i have 5 lines of text and i want to clear the 3rd line. is this possible. what functions to use

Code:

---

pspDebugScreenSetXY(0,3)
for(int loop = 0; loop < 68;loop++ ) pspDebugScreenPrintf(" ");

---

not sure about the 68 , remember if you printf something new to reset the offset to 6 if u dont want to overwrite line5

lol, i made a mistake. i printf the same thing twice so it didnt change

Zitat:

---

Zitat von Raphael

....that's because you place it at depth = 0... by any chance, take a read on perspective projection and it's formula, then think about how big your x/y needs to be to match a specific z value and why z = 0 will never do good.

---

Code:

---

        {       
                ScePspFVector3 move = { -1.1f, (0.0f - currentMenuOption), -4.0f };
                sceGumTranslate( &move );
        }

---

;)
-= Double Post =-
I got it:)))))))
My fault was to make a TGA of 16/bits the pixel ut it seems to only work with 32/bits the pixel:)

Zitat:

---

Zitat von hallo007

it seems to only work with 32/bits the pixel:)

---

Uh... no.

What generally causes a linker error, and what can I do to get rid of it?

-Aura

Linker errors can be caused by conflicting globals, missing globals, or...some other things.

What's the error?

0x8002013A -> library not yet linked

It only happens when I try to call a function from my kmode plugin, I've declared the function before any functions appear, and I've placed the stub in the makefile, not sure if I need to do anything else?

-Aura

Oh, I thought you meant a linker error when you were compiling.

...um, I've never seen that error before ._.

Hey guys, In my program, it's layed out something like this:
Into.c
Menu.c
Credits.c
Game.c
Pause.c
Sure.c

(Then the .h's for all of em).

Now, it should be kinda obvious how it works, it starts up with intro...goes to the menu, then you can start the game...Now, when I pause the game (Pause();), and use the "return to menu" thing I used, it will return to the menu..If you try to run the game again after you returned to the menu..the game will freeze. Anyone know what's wrong, or do you need more information?

Zitat:

---

Zitat von MrChaos

Hey guys, In my program, it's layed out something like this:
Into.c
Menu.c
Credits.c
Game.c
Pause.c
Sure.c

(Then the .h's for all of em).

Now, it should be kinda obvious how it works, it starts up with intro...goes to the menu, then you can start the game...Now, when I pause the game (Pause();), and use the "return to menu" thing I used, it will return to the menu..If you try to run the game again after you returned to the menu..the game will freeze. Anyone know what's wrong, or do you need more information?

---

Let's see:
Memory stamping
Stack corruption
Invalid or NULL pointer access
Stack overflow
Out of memory
Memory leaks

Take your pick.

Ive had this exact problem before, can i see your source code?

Zitat:

---

Zitat von BlackShark

Ive had this exact problem before, can i see your source code?

---

Yeah, here: (I uploaded it to my sites server):
http://evolve-psp.net/massacre.zip

im having a problem when using pspiofilemgr then assigning flash0 to USB in my app. everything works OK but when I go to mount flash0 as ms0 i get the following on screen error:

Zitat:

---

iofilemgr.c : sceIoUnassign : No such alias nams ms0:
prfile_mod.c : df_mount : lflash0:0,0 : Unsuported!!
iofilemgr.c : sceIoAssign : df_mount() : err: 0x800020325

---

Flash0 still gets mounted properly and reading and writing to it are OK, as far as i can tell. its just sort of annoying to have this error message in the middle of my app

Zitat:

---

Zitat von MrChaos

Yeah, here: (I uploaded it to my sites server):
http://evolve-psp.net/massacre.zip

---

You problem is that you are loading the MP3s completely into memory but it doesn't get freed due to your recursive function calls (i.e. Your functions NEVER end).

Therefore you are either:
- Running out of memory
- overflowing the stack

Zitat:

---

Zitat von yaustar

You problem is that you are loading the MP3s completely into memory but it doesn't get freed due to your recursive function calls (i.e. Your functions NEVER end).

Therefore you are either:
- Running out of memory
- overflowing the stack

---

I know about the MP3, but I still had the same problem before I even made the game load the MP3.

Oh, and...how should I fix that?

by trying on your own ...