Programming Windows Programming Guide-> Chapter 5 example program 7

/*_##################################### #######################################
_##
### Programming Windows Programming Design Guide-> Chapter 5 example program 7
_ ## Author: xwlee
_ ## Time: 2007.06.20
### Chang'an University
_ ## Development condition: win2003 SERVER + vc6.0
_##
_ ## Program 5-7 clover
_ ## Clover. c file
### Using complex cropping areas, you can draw these lines directly, and let windows determine its endpoint
_ ## The program is only for verification
_##
_##
_ ## Clover. c -- clover drawing program using regions
_ ## (C) Charles Petzold, 1998
_##
_####################################### ###################################*/

# Include <windows. h>

# Include <math. h>

 

# Define two_pi (2.0*3.14159)

Lresult callback wndproc (hwnd, uint, wparam, lparam );

Int winapi winmain (hinstance, hinstance hprevinstance,

Pstr szcmdline, int icmdshow)

{

Static tchar szappname [] = text ("clover ");

Hwnd;

MSG;

Wndclass;

Wndclass. Style = cs_hredraw | cs_vredraw;

Wndclass. lpfnwndproc = wndproc;

Wndclass. cbclsextra = 0;

Wndclass. cbwndextra = 0;

Wndclass. hinstance = hinstance;

Wndclass. hicon = loadicon (null, idi_application );

Wndclass. hcursor = loadcursor (null, idc_arrow );

Wndclass. hbrbackground = (hbrush) getstockobject (white_brush );

Wndclass. lpszmenuname = NULL;

Wndclass. lpszclassname = szappname;

If (! Registerclass (& wndclass ))

{

MessageBox (null, text ("this program requires Windows NT! "),

Szappname, mb_iconerror );

Return 0;

}

Hwnd = createwindow (szappname, text ("draw a clover "),

Ws_overlappedwindow,

Cw_usedefault, cw_usedefault,

Cw_usedefault, cw_usedefault,

Null, null, hinstance, null );

Showwindow (hwnd, icmdshow );

Updatewindow (hwnd );

While (getmessage (& MSG, null, 0, 0 ))

{

Translatemessage (& MSG );

Dispatchmessage (& MSG );

}

Return msg. wparam;

}

 

Lresult callback wndproc (hwnd, uint imsg, wparam, lparam)

{

Static hrgn hrgnclip;

Static int cxclient, cyclient;

Double fangle, fradius;

Hcursor;

HDC;

Hrgn hrgntemp [6];

Int I;

Paintstruct pS;

Switch (imsg)

{

Case wm_size:

Cxclient = loword (lparam );

Cyclient = hiword (lparam );

Hcursor = setcursor (loadcursor (null, idc_wait ));

Showcursor (true );

If (hrgnclip)

Deleteobject (hrgnclip );

Hrgntemp [0] = createellipticrgn (0, cyclient/3,

Cxclient/2, 2 * cyclient/3 );

Hrgntemp [1] = createellipticrgn (cxclient/2, cyclient/3,

Cxclient, 2 * cyclient/3 );

Hrgntemp [2] = createellipticrgn (cxclient/3, 0,

2 * cxclient/3, cyclient/2 );

Hrgntemp [3] = createellipticrgn (cxclient/3, cyclient/2,

2 * cxclient/3, cyclient );

Hrgntemp [4] = createrectrgn (0, 0, 1, 1 );

Hrgntemp [5] = createrectrgn (0, 0, 1, 1 );

Hrgnclip = createrectrgn (0, 0, 1, 1 );

 

Combinergn (hrgntemp [4], hrgntemp [0], hrgntemp [1], rgn_or );

Combinergn (hrgntemp [5], hrgntemp [2], hrgntemp [3], rgn_or );

Combinergn (hrgnclip, hrgntemp [4], hrgntemp [5], rgn_xor );

For (I = 0; I <6; I ++)

Deleteobject (hrgntemp [I]);

Setcursor (hcursor );

Showcursor (false );

Return 0;

Case wm_paint:

HDC = beginpaint (hwnd, & PS );

Setviewportorgex (HDC, cxclient/2, cyclient/2, null );

Selectcliprgn (HDC, hrgnclip );

Fradius = _ hypot (cxclient/2.0, cyclient/2.0 );

For (fangle = 0.0; fangle <two_pi; fangle + = two_pi/360)

{

Movetoex (HDC, 0, 0, null );

Lineto (HDC, (INT) (fradius * Cos (fangle) + 0.5 ),

(INT) (-fradius * sin (fangle) + 0.5 ));

}

Endpaint (hwnd, & PS );

Return 0;

Case wm_destroy:

Deleteobject (hrgnclip );

Postquitmessage (0 );

Return 0;

}

Return defwindowproc (hwnd, imsg, wparam, lparam );

}