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Started by bodhisatva_b July 07, 2006 04:42 PM

5 comments, last by bodhisatva_b 17 years, 9 months ago

bodhisatva_b

101

Author

July 07, 2006 04:42 PM

Hello ppl, I was reading "Game Programming All in One" by Bruno Miguel Teixeira de Sousa, and was on the chapter where he builds the Monster's Game Library. Seeing some of the functions I decided to try my hands at a short program which has a string which moves depending on keypress. Initially it felt simple enuf, however, wen i tried my hand at it, NOTHING WORKED! :( I am pretty new at programming, so plz pardon any noobie mistakes. Here is the code


#include&lt;iostream.h&gt;
#include&lt;windows.h&gt;
#include&lt;conio.h&gt;

//global variables
WORD m_background;
HANDLE m_screen;

void cleaner()
{
     COORD start;
     DWORD written;
     
     
     start.X=0;
     start.Y=0;
     m_background=0;
     
     
     
     
     FillConsoleOutputAttribute( m_screen, FOREGROUND_BLUE|m_background,640*480,start,&written);
     FillConsoleOutputCharacter(m_screen,' ',640*480,start,&written);
     
}


//this fn will draw my "stylized" name at the current cursor position
void draw(void)
{
     DWORD written;
     
     WriteConsole(m_screen,"~|bodhi|~",strlen("~|bodhi|~"),&written,NULL);
 }


//like it says, this will evaluate the position of the cursor at each keypress     
void calc_pos(COORD &current, char keypress)
{
      if (keypress=='w')
          current.Y+=1;
      
      if (keypress=='s')
          current.Y-=1;
      
      if (keypress=='a')
          current.X-=1;
          
      if (keypress=='d')
          current.X+=1;
             
}
     

//this fn will set the cursor to the position calc by the calc_pos fn above
void setpos(COORD pos)
{
     SetConsoleCursorPosition(m_screen,pos);
}
     



   
int main(){

//starting point @ the center of the console window WEN IT IS MAXIMISED
COORD current;
current.X=320;
current.Y=240;

//initialize the current input device as the monitor
m_screen= GetStdHandle(STD_OUTPUT_HANDLE);

char keypress='a';

cout&lt;&lt;"This is a tiny diagnostic program which \"diagnoses\" whether i can do stuff!";
cout&lt;&lt;endl&lt;&lt;" Use the w,s,a,d keys to move the text around, and press 0 to quit";
cout&lt;&lt;endl&lt;&lt;"Press any key to start!!";

//the "game loop"
while(keypress!='0')
{ 
keypress=getch();
calc_pos(current,keypress);
setpos(current);
cleaner();
draw();
}

cout&lt;&lt;endl&lt;&lt;"thank you for chkin this out!!";
getch();
return 0;
}

Could you help me correct the errors and make it work? Thanks a lot... [Edited by - bodhisatva_b on July 9, 2006 2:57:10 AM]

Any ship can be a minesweeper... once.

deathkrush

350

July 07, 2006 05:22 PM

What's the problem? The program doesn't compile or the string doesn't move?

deathkrushPS3/Xbox360 Graphics Programmer, Mass Media.Completed Projects: Stuntman Ignition (PS3), Saints Row 2 (PS3), Darksiders(PS3, 360)

yaustar

1,022

July 07, 2006 06:13 PM

It doesn't solve the problem but is something you missed. How does the draw function know where to draw the text if it doesn't have access to the COORD current?

Edit: Nevermind, you have a Goto Position function there..

Edit2:
Use <iostream> instead of <iostream.h>
0,0 is the top left of the console, not the bottem left.
Position x = 320 and y = 240 don't exist in the console.

Here is the fixed code (Escape is now quit):

#include<iostream>#include<windows.h>#include<conio.h>//global variablesWORD m_background;HANDLE m_screen;using namespace std;void cleaner(){    COORD start;    DWORD written;    start.X=0;    start.Y=0;    m_background=0;    FillConsoleOutputAttribute( m_screen, FOREGROUND_BLUE|m_background,640*480,start,&written);    FillConsoleOutputCharacter(m_screen,' ',640*480,start,&written);}//this fn will draw my "stylized" name at the current cursor positionvoid draw(void){    DWORD written;    WriteConsole(m_screen,"~|bodhi|~",strlen("~|bodhi|~"),&written,NULL);}//like it says, this will evaluate the position of the cursor at each keypressvoid calc_pos(COORD &current, char keypress){    if (keypress=='s')        current.Y+=1;    if (keypress=='w')        current.Y-=1;    if (keypress=='a')        current.X-=1;    if (keypress=='d')        current.X+=1;}//this fn will set the cursor to the position calc by the calc_pos fn abovevoid setpos(COORD pos){    SetConsoleCursorPosition(m_screen,pos);}int main(){//starting point @ the center of the console window WEN IT IS MAXIMISED    COORD current;    current.X=10;    current.Y=10;//initialize the current input device as the monitor    m_screen= GetStdHandle(STD_OUTPUT_HANDLE);    char keypress='a';    cout<<"This is a tiny diagnostic program which \"diagnoses\" whether i can do stuff!";    cout<<endl<<" Use the w,s,a,d keys to move the text around, and press 0 to quit";    cout<<endl<<"Press any key to start!!";//the "game loop"    while(keypress!=27)    {        keypress=getch();        calc_pos(current,keypress);        setpos(current);        cleaner();        draw();    }    cout<<endl<<"thank you for chkin this out!!";    getch();    return 0;}

Steven Yau
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bodhisatva_b

101

Author

July 07, 2006 08:55 PM

Thanks a lotttt!! :D
Tht fixed it. Well, mostly. Now, you said that the position 320x240 dont exist on the console and 0,0 is on the top left, i noticed that if i exceed the "bounds" of the console, crap hits the fan and all control is jacked. So, could you plz tell me wat is the max COORD of the X and Y axis using which i can do a "bounds-checking" when the key is pressed so that the txt doesnt exceed the console "bounds" and screws things up. Thanks a lot again for taking the effort to help me.

I added the bound checking for (0,0)

    if (keypress=='w')        {  if(current.Y>=0)              current.Y-=1;              }                  if (keypress=='a')        {  if (current.X>=0)              current.X-=1;              }

I get a peculiar problem, instead of "inaction" when i reach one of the X/Y axis, the text scrolls sideways. For instance, if i touch the top of the screen (meaning the X axis), and continue pressing 'w', then it starts scrolling to the right. Same is the case with the Y axis.

Edit: Oops. I'm quite the retard. I made the checking as "if(current.Y>=0)"
this causes it to get depreciated to -1 wen the location is 0. :D
(0,0) is resolved!! Whats the max value of X and Y?

PS: how do i get the code-box like thingy?

[Edited by - bodhisatva_b on July 7, 2006 9:55:53 PM]

Any ship can be a minesweeper... once.

yaustar

1,022

July 08, 2006 12:45 PM

Something like 80 and 40 respectively. I can't actually remember.

Code is [ source] and [ /source] with out the spaces.

Steven Yau
[Blog] [Portfolio]