//Practice tracing circles

I1 ct_buf[128];
double score=0,rad;

void EndSound()
{
  Sound(0);
  Exit;
}

void SoundTrackTsk()
{
  Fs->end_task_cb=&EndSound;
  while (TRUE) {
    Play("hEDCARCDECR");
  }
}

void DrawIt()
{
  ClearWindowText;
  PlotWindowString(ct_buf,0x0F,0,0);
}

#define cir_radius 100


void CTPlot(GrBitMap *base,I8 x,I8 y,I8 z)
{
  GrPlot(base,x,y);
  rad=Sqrt(Sqr(x-cir_radius-25)+Sqr(y-cir_radius-25));
  score+=Abs(rad-cir_radius);
}


void CircleTrace()
{
  I8 cmd,p1,p2,x1,y1;
  U4 old_update_window=Fs->update_window;
  U4 old_ip_double=Bts(&Fs->crt_flags,CRTf_NO_DOUBLE_CLICK);
  U4 old_inhibit=ip_inhibit_win_operations;
  U8 start_time;
  GrBitMap *base=GrNew(grbase);
  TssStruct *sndtsk=Spawn(&SoundTrackTsk);
  ip_inhibit_win_operations=TRUE;
  MaximizeWindow;
  Fs->update_window=&DrawIt;
  GrClear;
  base->color=ROP_XOR+(GR_BLACK ^ GR_WHITE);
  GrCircle(base,cir_radius+25,cir_radius+25,cir_radius);
  ct_buf[0]=0;
  FlushMsgs;
  while (TRUE) {
    cmd=GetMsg(&p1,&p2,
      (1<<MSG_KEY_DOWN)+(1<<MSG_IP_L_DOWN)+
      (1<<MSG_IP_R_UP));
    if (cmd==MSG_KEY_DOWN || cmd==MSG_IP_R_UP) {
      Fs->update_window=old_update_window;
      GrClear;
      AssignBit(&Fs->crt_flags,CRTf_NO_DOUBLE_CLICK,old_ip_double);
      ip_inhibit_win_operations=old_inhibit;
      GrDel(base);
      Kill(sndtsk);
      return;
    } else {
      GrClear;
      base->color=ROP_XOR+(GR_BLACK ^ GR_WHITE);
      GrCircle(base,cir_radius+25,cir_radius+25,cir_radius);
      base->color=ROP_XOR+(GR_RED ^ GR_WHITE);
      score=0;
      start_time=BootTime;
      x1=p1; y1=p2;
      while (cmd!=MSG_IP_L_UP) {
	while (cmd=GetMsgNoWait(&p1,&p2,
  	  (1<<MSG_IP_L_UP)+(1<<MSG_IP_MOVE))) {
	  if (cmd==MSG_IP_L_UP)
	    break;
	  if (x1!=p1 || y1!=p2) {
	    Line(base,x1,y1,0,p1,p2,0,&CTPlot);
	    x1=p1;y1=p2;
	    //undo overlapping pixels on segments
	    GrPlot(base,x1,y1);
	    rad=Sqrt(Sqr(x1-cir_radius-25)+Sqr(y1-cir_radius-25));
	    score-=Abs(rad-cir_radius);
	  }
	}
	SPrintF(ct_buf,"Score:%9.2f Time:%h17T",score/(pi2*cir_radius),BootTime-start_time);
	Sleep(50);
      }
    }
  }
}

CircleTrace;  //Execute when #included
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