Thread: Draw and move

Hello. I've been working on simple Chess game. I got troble, when I move figure from one cell to another, the figure wipes off in the old cell, but doesn't appeaer in new one, although there is a pointer to figure in new cell. Can anyone offer some ideas what's is wrong? Thanks) This is part of code, when move realizes.

Code:

class Cell
{
      public:
        int x,y,size,color;
        Figure *figure;
      Cell(int cx=0,int cy=0,int cl=LIGHTGRAY,int csize=40)
               {
               x=cx;
               y=cy;
               color=cl;
               size=csize;
               figure=NULL; 
               }
      void showC()
      {
              setfillstyle(1,color);  
              bar(x,y,x+size,y+size);
              if (figure!=NULL)
              figure->draw();  
      }
      int getcolor()
      {
          return color;
      }   
};

class Field
{
      protected:
      int x,y,size;
      Cell f[8][8];
      Chose *rama;
      Figure *figure;
      public: 
      Field(int fx,int fy,int fsize=400)
      {
              x=fx;
              y=fy;
              size=fsize;
              int sc=size/8;
              if(size%8!=0)
              size=sc*8;
              rama=NULL;
      for(int i=0;i<8;i++)
          {
          for(int j=0;j<8;j++) 
            {
               if((i+j)%2==0)
                  f[i][j]=Cell(j*sc,i*sc,LIGHTGRAY,sc);
                  else
                  f[i][j]=Cell(j*sc,i*sc,DARKGRAY,sc);
            }
          }
          f[0][0].figure=new Rook(BLACK,20,15);
          f[0][1].figure=new Horse(BLACK,70,15);
          f[0][2].figure=new Bishop(BLACK,120,15);
          f[0][3].figure=new King(BLACK,170,15);
          f[0][4].figure=new Queen(BLACK,220,15);
          f[0][5].figure=new Bishop(BLACK,270,15);
          f[0][6].figure=new Horse(BLACK,320,15);
          f[0][7].figure=new Rook(BLACK,370,15);
          
          f[7][0].figure=new Rook(WHITE,20,365);
          f[7][1].figure=new Horse(WHITE,70,365);
          f[7][2].figure=new Bishop(WHITE,120,365);
          f[7][3].figure=new Queen(WHITE,170,365);
          f[7][4].figure=new King(WHITE,220,365);
          f[7][5].figure=new Bishop(WHITE,270,365);
          f[7][6].figure=new Horse(WHITE,320,365);
          f[7][7].figure=new Rook(WHITE,370,365);
          


         for (int i=0;i<8;i++) 
            {
            x=20+sc*i;
             f[1][i].figure=new Pawn(BLACK,x,55);
            f[6][i].figure=new Pawn(WHITE,x,305);
            }  
        rama=new Chose(5,5,45,45);  
     }
        
void Show()
      {
           x=0;y=0;
        rectangle(x,y,x+size,y+size);   
       for(int i=0;i<8;i++)
          {   
          for(int j=0;j<8;j++)
            f[i][j].showC();
          }
        rama->dChose();      
      }    


           
void Data(data &mes)
{   
     mes.color=f[rama->y / rama->size][rama->x / rama->size].getcolor();   
     switch(mes.code)
     {
     case 0: if(f[rama->y / rama->size][rama->x / rama->size].figure!=NULL )
             {   
             mes.i=rama->x;
             mes.j=rama->y;  
             mes.code=1; break; 
             }
     case 1: if(getch()==13)
             { 
               mes.desti=rama->x;
               mes.destj=rama->y; 
               if(f[mes.j / rama->size][mes.i / rama->size].figure->IsLegalMove(mes.i,mes.j,mes.desti,mes.destj)==1)
               moveto(mes);
               mes.code=2;
               break;
              }           


     } 
   
        
}   
   
   
   
void moveto(data &mes)
{   
f[mes.destj / rama->size][mes.desti / rama->size].figure=f[mes.j / rama->size][mes.i / rama->size].figure;
f[mes.destj / rama->size][mes.desti / rama->size].showC();
f[mes.j / rama->size][mes.i / rama->size].figure=NULL;
f[mes.j / rama->size][mes.i / rama->size].showC();          
}


};

Originally Posted by Alpo

Without knowing how you are rendering, or in what order it's hard to evaluate anything but the logic of how you are moving. It looks like in the function moveto() you could be assigning a pointer to figure to the new position, and then assigning that pointer NULL a few lines later. As your code appears to be doing a NULL check to decide whether to render the figure, it wouldn't show up if this is the case.

Code:

f[mes.destj / rama->size][mes.desti / rama->size].figure=f[mes.j / rama->size][mes.i / rama->size].figure;
f[mes.destj / rama->size][mes.desti / rama->size].showC();
f[mes.j / rama->size][mes.i / rama->size].figure=NULL;
f[mes.j / rama->size][mes.i / rama->size].showC(); 

Edit: On second thought, that looks like a red herring. Maybe check to make sure you aren't rendering over the figure while drawing the board.

I don't think I render drawing board over figures, I call for Data(Game) after drawing the board.

Code:

int main()
{
initwindow(400,400);
Field desk(0,0,400);
desk.Show();
data mes;
mes.code=5;
while(k!=4)
{
      desk.Game(mes); // Game includes Data        
}             


getch();
}

About function moveto(). What I think is going on there:

Code:

f[mes.destj / rama->size][mes.desti / rama->size].figure=f[mes.j / rama->size][mes.i / rama->size].figure; // I assign pointer of figure in the old cell to new cell(now there is a poiner to figure in the new cell
f[mes.destj / rama->size][mes.desti / rama->size].showC(); // redraw new cell, and now, that there is a pointer, it should be with picture 
f[mes.j / rama->size][mes.i / rama->size].figure=NULL; // delete pointer in old cell
f[mes.j / rama->size][mes.i / rama->size].showC(); // redraw old cell, wipes off figure and now it's an empty cell

Am I right? Or the pointer in a new cell is NULL? Do I assign a pointer to new cell correctly? I have another thought, maybe something's wront with figures' coordinates? For example,

Code:

f[0][1].figure=new Horse(BLACK,70,15);

This figure has these coordinates. Do they change when I move it? Cos I think, I don't change coordinates. Or they change?

Code:

virtual void draw()
{                     
     if(color==BLACK)
      setcolor(WHITE);
     else 
          setcolor(BLACK);
     setbkcolor(color);
     outtextxy(x,y,"H");
}

Originally Posted by Alpo

It is hard to tell if the positions are changing on a move, as I don't know what mes::code means (you should definitely be using constants to solve this). You should go through with a debugger (or use printing functions) to check the values. Pay attention to both positions and color of the figure being drawn, and check them against the corresponding cells.

Thanks for help, but using const didn't help(
mes.code means evants: mes.cod=0 - evant 1, enter was clicked
mes.code=1 - evant 2, enter was clicked the second time and here move figure happens

I tried printf function, and it shoes right values for mes.i, mes.j, mes.desti, mes.destj and for
f[mes.destj / rama->size][mes.desti / rama->size]
f[mes.j / rama->size][mes.i / rama->size]

And debugger shows, thar there is a pionter in

Code:

f[mes.destj / rama->size][mes.desti / rama->size], ma->size].showC();

Could you please look at the pictures.
Second picture is for line

Code:

f[mes.destj / rama->size][mes.desti / rama->size].figure=f[mes.j / rama->size][mes.i / rama->size].figure;

First picture after moveto()
Coordinates aren't match.