[C大程]图形程序设计_3　随笔画

#include "graphics.h"
#include "extgraph.h"
#include "genlib.h"
#include "simpio.h"
#include "conio.h"
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>

#include <windows.h>
#include <olectl.h>
#include <stdio.h>
#include <mmsystem.h>
#include <wingdi.h>
#include <ole2.h>
#include <ocidl.h>
#include <winuser.h>

int cx,cy;

bool inBox(double x0, double y0)
{
	return (x0 > 0 && x0 < cx && y0 > 0 && y0 < cy);
}

void MouseEventProcess(int x, int y, int button, int event)
{ 
	static double lx=0.0, ly=0.0;
    double mx, my;
 	 mx = ScaleXInches(x);/*pixels --> inches*/
 	 my = ScaleYInches(y);/*pixels --> inches*/
 	 static bool isDraw = FALSE;
 
     switch (event) {
         case BUTTON_DOWN:
   		 	  if (button == LEFT_BUTTON){
				  isDraw = TRUE;	
   		 	} 
              break;
    	 case BUTTON_DOUBLECLICK:
			  break;
         case BUTTON_UP:
  		 	  if (button == LEFT_BUTTON) isDraw = FALSE;
              break;
         case MOUSEMOVE:
			  if (isDraw) {
			  	  DrawLine(mx-lx,my-ly);
			  	  MovePen(mx,my);
			  } 
              break;
     }	
     lx=mx;
     ly=my;
}


void Main()
{
    InitGraphics();        	
	cx = GetWindowWidth();
    cy = GetWindowHeight();
	registerMouseEvent(MouseEventProcess);
    SetPenSize(1);
}