Subj : I need you advice and talent
To   : borland.public.cpp.borlandcpp
From : Jackzhang
Date : Wed May 05 2004 02:35 am


I am sorry to trouble everyone but I have a very important question and I must resolve it as quickly as possible so I need your 
advice.And the question is :how can I draw a circle corrently.My
program follows:
#include <struct.h>
#include <conio.h>
#include <math.h>
#include <dos.h>
#include <iostream.h>
#include "driver.h"
#include "composit.h"
#include "updown.h"
#define ty_speed  4000
#ifdef __cplusplus
extern "C"
{
#endif
void G0203TG();
void setg0203();
void wayg02();
void wayg03();
#ifdef __cplusplus
}
#endif
extern upprocess(int);
extern downprocess();
extern composition();
extern FEED_BACK1;
extern PLANE1_FLAG;
extern long X_COUNT,Y_COUNT,Z_COUNT,X_AXIE,Y_AXIE,Z_AXIE, X_CENTER,Y_CENTER,Z_CENTER;
extern ALL_END;
extern int G00_Speed;
extern char Simulation_Flag;
extern unsigned int Simulation_Speed;
extern unsigned int test_speed;
extern updown *ud;
extern driver *dr;
extern compensation *jx;
extern int X_reginal,Y_reginal,Z_reginal ;//from composit.cpp
extern int X_derect,Y_derect,Z_derect;//from composit.cpp
extern char flag;
extern  uptable *ty_ut;
extern int Ty_pause_Flag;
extern int continue_flag;
extern int Ty_esc_flag;
extern int Darwinist_times;
extern char Dar_forb_flag;
extern int current_speed;
extern long distance,max_count;

long OpStPoint_x, OpStPoint_y, OpStPoint_z;
long integrator_x, integrator_y, integrator_z;
long X_TOTAL,Y_TOTAL,Z_TOTAL;
long Constant;
long sum_integrator_x, sum_integrator_y,sum_integrator_z;
float radils;
char overflow_flag_x, overflow_flag_y, overflow_flag_z;
char wayflag;
void wayg02() {wayflag=1;}   //operation direction
void wayg03() {wayflag=-1;}
void setg0203()
{
 ty_ut=ud->read_uptable();
 int m=0,n=55;
 int find_flag=1;
 max_count=0; distance=0;
 test_speed=FEED_BACK1; 
 FEED_BACK1=test_speed*(1+Darwinist_times/20.0);     //Darwinist_times 
if(FEED_BACK1>=G00_Speed) FEED_BACK1=G00_Speed;
 ud->set_multiple(1);
 sum_integrator_x=0; sum_integrator_z=0; sum_integrator_y=0;
 X_TOTAL=labs(X_COUNT); Y_TOTAL=labs(Y_COUNT); 
Z_TOTAL=labs(Z_COUNT);
 OpStPoint_x=-X_CENTER; OpStPoint_y=-Y_CENTER;
 OpStPoint_z=-Z_CENTER;

 radils=sqrt(OpStPoint_x*OpStPoint_x+OpStPoint_y*OpStPoint_y+OpStPoint_z*OpStPoint_z);
 Constant=long(radils+0.5);
 switch(PLANE1_FLAG)  //chose the opetation surface
 {
  case 1:
integrator_x=wayflag*(-OpStPoint_y)/ud->read_multiple();
integrator_y=wayflag*OpStPoint_x/ud->read_multiple();
integrator_z=0;
break;
case 2:
integrator_x=wayflag*(-OpStPoint_z)/ud->read_multiple();
integrator_z=wayflag*OpStPoint_x/ud->read_multiple();
integrator_y=0;
break;
case 3:
integrator_y=wayflag*(-OpStPoint_z)/ud->read_multiple();
integrator_z=wayflag*OpStPoint_y/ud->read_multiple();
integrator_x=0;
break;
 }

 max_count=max(X_TOTAL,Y_TOTAL);
 max_count=max(max_count,Z_TOTAL);
 max_count=max_count*ud->read_multiple();   
 do{
if(max_count>=2*ud->read_multiple()*ty_ut[n].sigam) break;
else if(max_count>=2*ud->read_multiple()*ty_ut[n-1].sigam)
	  {if(FEED_BACK1>=ty_ut[n-1].feed)
		FEED_BACK1=ty_ut[n-1].feed;
		break;}
	  n--;
  }while(n>=1) ;
 if(n==0) FEED_BACK1=ty_ut[0].feed;
 do{
	if(FEED_BACK1<=ty_ut[m].feed)
	  { distance=ud->read_multiple()*ty_ut[m].sigam;    
		 find_flag=0;
	  }
	  m++;
	}while(find_flag) ;
 if(Simulation_Flag) ud->set_speed(Simulation_Speed);  
 else ud->set_speed(FEED_BACK1);

 ud->set_updown_flag(Up_And_Down);
 dr->set_forbidden_tag(Simulation_Flag);
}

void 	G0203TG()
{
 if(Ty_pause_Flag&&Ty_esc_flag)
	if(ud->read_play_speed()<=100)
		return;
jx->judge( X_derect, Y_derect, Z_derect, X_reginal,Y_reginal,Z_reginal);
 if(jx->read_compflag())
	if(jx->execute())
		return;

 max_count--;       
 flag=ud->execute();//the fuction is used for determin the 
8253A interrupt time
 if(flag==Up_Completed)
	{ 
		ud->set_status(Completed);
		Dar_forb_flag=1;
	}
 if(max_count<=distance)
	 {// cout<<"\nnow down"<<endl;cout<<max_count;
	 ud->set_status(Down_Status);Dar_forb_flag=0;}

 overflow_flag_x=0;
 overflow_flag_y=0;
 overflow_flag_z=0;
 if(X_COUNT!=0)
        {  sum_integrator_x+=integrator_x;
           if(sum_integrator_x>=Constant)
	  { sum_integrator_x-=Constant;
	    overflow_flag_x=1;
	    X_AXIE++;
	    X_COUNT--;
	   dr->insert_to_output(X_Axes,Plus_Direction);
	   X_derect=1;
	   }
	if(sum_integrator_x<=-Constant)
	{ sum_integrator_x+=Constant;
           overflow_flag_x=1;
	  X_AXIE--;
	  X_COUNT++;
	 dr->insert_to_output(X_Axes,Minus_Direction);
           X_derect=-1;
	}
     }
 if(Y_COUNT!=0)
    { if(sum_integrator_y>=Constant)
       { sum_integrator_y-=Constant;
         overflow_flag_y=1;
         Y_AXIE++;
         Y_COUNT--;
        dr->insert_to_output(Y_Axes,Plus_Direction);
        Y_derect=1;
      }
    if(sum_integrator_y<=-Constant)
      { sum_integrator_y+=Constant;
        overflow_flag_y=1;
        Y_AXIE--;
        Y_COUNT++;
        dr->insert_to_output(Y_Axes,Minus_Direction);
        Y_derect=-1;
       }
    }
 if(Z_COUNT!=0)
   {  sum_integrator_z+=integrator_z;
      if(sum_integrator_z>=Constant)
       { sum_integrator_z-=Constant;
         overflow_flag_z=1;
	Z_AXIE++;
	Z_COUNT--;
	dr->insert_to_output(Z_Axes,Plus_Direction);
	Z_derect=1;
        }
     if(sum_integrator_z<=-Constant)
       { sum_integrator_z+=Constant;
	overflow_flag_z=1;
	Z_AXIE--;
	Z_COUNT++;
	dr->insert_to_output(Z_Axes,Minus_Direction);
	Z_derect=-1;
        }
     }
  switch(PLANE1_FLAG)
    {
    case 1:
	if(overflow_flag_x)integrator_y+=wayflag;
	if(overflow_flag_y)integrator_x+=(-wayflag);
	break;
   case 2:
	if(overflow_flag_x)integrator_z+=(-wayflag);
         if(overflow_flag_x)integrator_x+=wayflag;
	break;
   case 3:
         if(overflow_flag_y)integrator_z+=wayflag;
	if(overflow_flag_z)integrator_y+=(-wayflag);
         break;
	}
 if(X_COUNT==0&&Y_COUNT==0&&Z_COUNT==0)
	  	ALL_END=1;
			
     dr->output();
}
I use the method DDA to realize drawing a circle.
the main trouble I think is the fuction itself,not relative to 
others.Could you do me a favor and point to the flaws and corrent
it.thank you very much.
My email is zhangjianke629@hotmail.com    OR
            zhangjianke629@yahoo.com.cn

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