C/C++ Programming Help Thread

[FreePlay]

well, you learn something new every day :)

[Beat_Bob]

Argh that code didnt work.
Could you use the code I sent on page 546 please?

[SG57]

Beat_Bob - If you actually heard yourself, youd realize why no one can help you. Right now i have 40 post p/page, making this page 138. Id rater not do the math just to find your problem, if all else fails give us the post number, or better yet a quote of the damn post to save us the trouble, thats the least you could do if you are asking for help. Lazy *******...

yaustar - does your job accept things like that (assuming C doesnt support passing by reference, so assumptions really)?

off topic:

btw, G4 had a big harry potter OotP special the other day, it talked about the game and how they walked on the set and took tons of pictures of 'hogwarts' (and were given blue prints) and have been able to recreate 'hogwarts' to match the movie's scenery. All of if for a game... shows alot of dedication. big props to the development team (last thing, are you a harry potter fanatic? or are you just in it for the pay... i can only find myself on projects that im very interested and dedicated to... is that bad? id say yes as dedication fades as time flows, resulting in a flop... :'()

[coolguy5678]

Anyone know why this isnt working?

Spoiler for code:

while(1)
{
sceCtrlPeekBufferPositive (&pad, 1); // Find out what the state of the control pad is
// Change the position of the box
if(pad.Buttons & PSP_CTRL_LEFT)
{
if(box.x>0)
{box.x=box.x-3;}
}
else if(pad.Buttons & PSP_CTRL_RIGHT)
{
if(box.x<480-32)
{box.x=box.x+3;}
}

if((pad.Buttons & PSP_CTRL_CROSS) && (box.state==0))
{box.state=1; box.jumpspeed=0;}

if(box.state==1 && box.jumpspeed==0)
{ box.y=box.y-0.8;
box.jumpspeed+=0.3;}

if (box.state==1 && box.jumpspeed>3.5)
{box.y=box.y-0.3;}

if (box.state==1 && box.jumpspeed>=5);
{
box.state=2;
}

if (box.state==2)
{
box.jumpspeed=5;
box.y+=0.8;}

if (box.state==2 & box.y==230)
{box.y=230; box.state=0;
box.jumpspeed=0;}

No errors or anything, its just that when I try to jump (when I press X) he doesnt do anything. I want him to go in the air and have gravity come down on him (when jumpspeed=5) thats when I want him to start coming down.
Then when hes back on the ground (when hes at y: 230) it resets.
box.state (0 = ground, 1 = jumping, 2 = falling) just so you know.
Anyone?

Didnt work. But I tried another way by converting a lua tutorial (just jumping, same method)
to this way:

Spoiler for while(1) loop:

sceCtrlPeekBufferPositive (&pad, 1); // Find out what the state of the control pad is
// Change the position of the box
if(pad.Buttons & PSP_CTRL_LEFT)
{
if(box.x>0)
{box.x=box.x-3;}
}
else if(pad.Buttons & PSP_CTRL_RIGHT)
{
if(box.x<480-32)
{box.x=box.x+3;}
}

if((pad.Buttons & PSP_CTRL_CROSS) && (box.state==0))
{box.state=1;}
if(box.state==1)
{box.jumpspeed = box.jumpspeed-0.5;
box.gravity=box.gravity-box.jumpspeed;}

if (box.gravity<0)
{box.state=2;}
if ((box.gravity < 230) && (box.state==2))
{box.gravity=box.gravity + (box.jumpspeed+3);}

if (box.gravity==230)
{box.jumpspeed=10;
box.state=0;}
if(box.gravity>230)
{box.gravity=230;}

box.y=box.gravity;

Its weird. When I press X he jumps (incredibly fast....) and hes just stuck in the air then.
He wont fall back down. Why not? Ive made it so I can move left and right, and when im stuck in the air im able to move
left and right by the way, just so you know.

Those are all of Beat_Bob's posts on page 546.

[JaSo PsP]

im making a snake game, i can get a snake that is 5 blocks long to move around the screen using the directional buttons. Ive tried to make it add blocks to the snake but i cant seem to make it work correctly. Im not going to post the code, because its not the codr that is the problem. Here's what the situation is:

The snake starts like this: (H = head, b# = body part)

b4 b3 b2 b1 H

then when it moves the head moves forward and b4 goes to the old position of the head:

b3 b2 b1 b4 H

The body parts are an array of structures that hold the X and Y coords of themsleves. The snake length variable holds the length of the snake and during run time, each part of the snake is blitted to the screen according to the co-ordinates it hold. Now, heres where i ran into the problem. When i add a new part of the body, it has to insert it at the end of the array, meaning there is only one position that it will add the block instantly. For example: (F = Food)

b2 b1 b4 b3 H F  ->  b2 [b1b5] b4 b3 H

The new block overlaps the old one and the snake only appears longer when the snake is at is original state:

b5 b4 b3 b2 b1 H

So, there you have it, does anyone know the solution to this problem or have made a snake game themselves?

PS: if you really want to look at the code, here it is:

Spoiler for Code:

#include <pspdisplay.h>
#include <pspctrl.h>
#include <pspkernel.h>
#include <pspdebug.h>
#include <pspgu.h>
#include <png.h>
#include <stdio.h>
#include "graphics.h"

PSP_MODULE_INFO( "Snake", 0, 1, 1 );
typedef enum _bool { false, true } bool;

/* Exit callback */
int exit_callback(int arg1, int arg2, void *common) {
          sceKernelExitGame();
          return 0;
}

/* Callback thread */
int CallbackThread(SceSize args, void *argp) {
          int cbid;

          cbid = sceKernelCreateCallback("Exit Callback", exit_callback, NULL);
          sceKernelRegisterExitCallback(cbid);

          sceKernelSleepThreadCB();

          return 0;
}
/* Sets up the callback thread and returns its thread id */
int SetupCallbacks(void) {
          int thid = 0;

          thid = sceKernelCreateThread("update_thread", CallbackThread, 0x11, 0xFA0, 0, 0);
          if(thid >= 0) {
                    sceKernelStartThread(thid, 0, 0);
          }

          return thid;
}

typedef struct
{
        int x;
        int y;
} BodyPart;

void DrawBody();
void InitBody();

Image* Head;
Image* Back;
Image* Body;

BodyPart bodyParts[30];

enum{ DIR_UP, DIR_LEFT, DIR_RIGHT, DIR_DOWN };

int headX, headY, oldX, oldY;
int moveCount;
int dir;
int snakeLength, oldLength;
int i;
int back;

bool exitFlag;
bool newPart;

SceCtrlData pad;

int main()
{
    SetupCallbacks();
    initGraphics();
    
    headX = 80;
    headY = 80;
    
    moveCount = 0;
    
    snakeLength = 3;
    back = snakeLength;
    
    Head = loadImage( "body.png" );
    Back = loadImage( "back.png" );
    Body = Head;
    
    dir = DIR_RIGHT;
    
    exitFlag = false;
    newPart = false;
    
    InitBody();
    
    while( exitFlag == false )
    {
           clearScreen(0);
           sceCtrlReadBufferPositive(&pad, 1);
           
           blitAlphaImageToScreen( 0, 0, 480, 272, Back, 0, 0 );
           blitAlphaImageToScreen( 0, 0, 16, 16, Head, headX, headY );
           DrawBody();
           
           if( pad.Buttons & PSP_CTRL_UP )
               dir = DIR_UP;
           
           if( pad.Buttons & PSP_CTRL_DOWN )
               dir = DIR_DOWN;
           
           if( pad.Buttons & PSP_CTRL_LEFT )
               dir = DIR_LEFT;
           
           if( pad.Buttons & PSP_CTRL_RIGHT )
               dir = DIR_RIGHT;
           
           if( pad.Buttons & PSP_CTRL_START )
               exitFlag = true;
           
           if( moveCount >= 30 )
           {
               oldX = headX;
               oldY = headY;
               
               if( pad.Buttons & PSP_CTRL_CROSS )
               {
                    newPart = true;
               }
               
               switch( dir )
               {
                       case DIR_UP:
                            headY -= 16;
                            break;
                       
                       case DIR_DOWN:
                            headY += 16;
                            break;
                       
                       case DIR_LEFT:
                            headX -= 16;
                            break;
                       
                       case DIR_RIGHT:
                            headX += 16;
                            break;
                       
                       default:
                            break;
               }
               moveCount = 0;
               
               if( newPart == true )
               {
                   oldLength = snakeLength;
                   snakeLength++;
                   bodyParts[snakeLength].x = bodyParts[oldLength].x;
                   bodyParts[snakeLength].y = bodyParts[oldLength].y;
                   newPart = false;
               }
               
               bodyParts[back].x = oldX;
               bodyParts[back].y = oldY;
               if( back == 0 )
               {
                   back = snakeLength;
               }   
               else
               {
                   back--;
               }
           }
           
           flipScreen();
           moveCount++;
    }
    sceKernelExitGame();
    return 0;
}

void InitBody()
{
     bodyParts[0].x = 64;
     bodyParts[0].y = 80;
     
     bodyParts[1].x = 48;
     bodyParts[1].y = 80;
     
     bodyParts[2].x = 32;
     bodyParts[2].y = 80;
     
     bodyParts[3].x = 16;
     bodyParts[3].y = 80;
}

void DrawBody()
{
     for( i = 0; i < (snakeLength+1); i++ )
     {
          blitAlphaImageToScreen( 0, 0, 16, 16, Body, bodyParts[i].x, bodyParts[i].y );
     }
}

please help me, everyone just ignored me before...

[myschoo]

my mate made snake before, but its in debug screen... i have src if you are interested...

[coolguy5678]

My idea would be to move each segment forward each time instead of just moving the last segment to the front. That way, you'd always be in the "original state".

[Raphael]

No, you can only pass by pointer in C.

Edit: I stand corrected. I just tried this an you can pass by reference in C.

You sure you didn't compile it with -libstdc++ linked or sth? I'm 95% sure C (as in ANSI-C and C-99) don't support the by-reference ampersand modifier in function declarations:

void byreference( int& x, int& y )
{
}

Compiler gives (as expected):

$ make
psp-gcc -I. -Ic:/cygwin/usr/local/pspdev/psp/sdk/include -O2 -G3 -g -Wall -D_PSP
_FW_VERSION=150 -c -o test.o test.c
test.c:11: error: expected ';', ',' or ')' before '&' token
test.c: In function 'main':
test.c:32: warning: implicit declaration of function 'byreference'
test.c:36: warning: too many arguments for format
make: *** [test.o] Error 1

EDIT:
I searched the C99 spec from open-std.org and couldn't find anything about "by-reference" parameters as in the C++ standard.
http://www.open-std.org/JTC1/SC22/WG...docs/n1124.pdf

[JaSo PsP]

My idea would be to move each segment forward each time instead of just moving the last segment to the front. That way, you'd always be in the "original state".

yeh, i read up on the main concept of a snake game, if i move the snake using the rear block first, moving to the co-ordinates of the one in front of it, i would not have to store the x and x variables in any other structure.

[coolguy5678]

yeh, i read up on the main concept of a snake game, if i move the snake using the rear block first, moving to the co-ordinates of the one in front of it, i would not have to store the x and x variables in any other structure.

Yes, that's what I was thinking of.

[yaustar]

AdjutantReflex: I am not a Harry Potter fanatic although I don't detest it either. The pay is relatively irrelevant, I like the team, the technology we are working with is cool and the story allows for interesting game mechanics and challenges.

Raphael: Hmm, Code::Blocks was using g++ even though it was a C file which was probably why it worked :/. I though it seemed weird when it did work.

[slicer4ever]

@yauster GJ with the game

@beat_bob
i'll look over your code and try and find the prob although i'm sticking to my old post as the reason

although i rly hate the way you place ur bracket's it makes it hard(for me anyways) to determine the open and clossing of brackets sometimes

[coolguy5678]

I think the indentation just got broken when copy-pasting it into the forum or something.

[sony psp player]

To the 3D developers: What do I have to learn to make a 3D game? Are there any good tutorials?

Thanks, sony_psp_player

[slicer4ever]

psp-programming.com i'll give a direct link to the tut in 1 sec
-= Double Post =-
here:

http://www.psp-programming.com/code/...id=c:tutorials

[Mr305]

To the 3D developers: What do I have to learn to make a 3D game? Are there any good tutorials?

Thanks, sony_psp_player

No... Learn Basics of OpenGL first... Trust me.

[slicer4ever]

why? i learned 3d first on psp...well actual first using flash but still

[sony psp player]

Yes, I know this one, but how, for example, can I draw a car and display it with the PSP? It wouldn't be easy if I had to define every triangle myself.

[Mr305]

Yes, I know this one, but how, for example, can I draw a car and display it with the PSP? It wouldn't be easy if I had to define every triangle myself.

use slicers .x loader.

[slicer4ever]

look into pspjunkie(i believe it's his) md2 loader
@mr305 i'm still working on it it's been a little post poned as i'm working on celestial cunning right now

[sony psp player]

I can't find it, please give me a link.

Btw: how do I create md2 files?

[slicer4ever]

u need an 3d modeler(calagary gamespace 1.5 is what i use but costs a little bit) but there are free one's like blender and...well i only know of blender also one moment i'll find it
-= Double Post =-
heres the link:
http://jparishy.com/wp/source-code/
however the site appears to be temporarily disabled

[Archaemic]

Um, www.blender.org

You'll need to install Python 2.5, too.

[pspballer07]

a quick google search for md2
http://tfc.duke.free.fr/coding/md2-specs-en.html

thats everything you'll need to know...i think...

I made an md2 loader/animator but pspjunkie did too
At the same time i think cuz he showed his without animation while I was working on mine and I made animation the same day lol I'm sure he's got animation too.

Rendering shouldn't be hard as long as ur familiar with PSPGU and GL

Gmax is a good modeling program too (so is 3d studio max) but gmax doesn't export md2 so u will have to get a plugin

[sony psp player]

Ok, I will play around with this. Thanks for your quick replies!

[cosito]

can someone help me I am tring to figure out how to patch a source code.
it is just to fix one thing.

[slicer4ever]

can't help you if you give us nothing

[cosito]

ok all I need to do is this,

char * standardkeys[4][3] =
{
{ ".,[email protected]\"'`:;()<>[]{}1", "abcABC2", "defDEF3" },
{ "ghiGHI4", "jklJKL5", "mnoMNO6" },
{ "pqrsPQRS7", "tuvTUV8", "wxyzWXYZ9" },
{ "", "/-~=_*xx+###$c€£S%&\\^| 0", "" }
};


to this

// Note: \001 indicates a char we can't type directly (e.g 'multiply').
char * standardkeys[4][3] =
{
{ ".,[email protected]\"'`:;()<>[]{}1", "abcABC2", "defDEF3" },
{ "ghiGHI4", "jklJKL5", "mnoMNO6" },
{ "pqrsPQRS7", "tuvTUV8", "wxyzWXYZ9" },
{ "", "/-~=_*\001\001+#\001\001$\0 01\001\001\001%&\\^| 0", "" }
};


all it is is fixing a problem with pikey
instead of x I get x(multiply) so urls don't work.
-= Double Post =-
how do I resave the file in c
since the it is a c file
-= Double Post =-
or would I just have to use cygwin and have it make it?

[coolguy5678]

Yes. Change the C file, save it, then run make again.

[Beat_Bob]

Didnt work. But I tried another way by converting a lua tutorial (just jumping, same method) to this way:

Spoiler for while(1) loop::

sceCtrlPeekBufferPositive (&pad, 1); // Find out what the state of the control pad is
// Change the position of the box
if(pad.Buttons & PSP_CTRL_LEFT)
{
if(box.x>0)
{box.x=box.x-3;}
}
else if(pad.Buttons & PSP_CTRL_RIGHT)
{
if(box.x<480-32)
{box.x=box.x+3;}
}

if((pad.Buttons & PSP_CTRL_CROSS) && (box.state==0))
{box.state=1;}
if(box.state==1)
{box.jumpspeed = box.jumpspeed-0.5;
box.gravity=box.gravity-box.jumpspeed;}

if (box.gravity<0)
{box.state=2;}
if ((box.gravity < 230) && (box.state==2))
{box.gravity=box.gravity + (box.jumpspeed+3);}

if (box.gravity==230)
{box.jumpspeed=10;
box.state=0;}
if(box.gravity>230)
{box.gravity=230;}

box.y=box.gravity;

Its weird. When I press X he jumps (incredibly fast....) and hes just stuck in the air then.
He wont fall back down. Why not? Ive made it so I can move left and right, and when im stuck in the air im able to move
left and right by the way, just so you know.

Do I really have to tell you? Just look at the last post of mine on that page. Not really that difficult.