windows 加载位图的代码
// 位图实验.cpp : 定义应用程序的入口点。
//
#include "stdafx.h"
#include <windows.h>
LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName [] = TEXT ("BitMask") ;
HWND hwnd ;
MSG msg ;
WNDCLASS 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 (LTGRAY_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 ("Bitmap Masking Demo"),
WS_OVERLAPPEDWINDOW| WS_VSCROLL | WS_HSCROLL,
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 hwnd, UINT message, WPARAM wParam,LPARAM lParam)
{
static HBITMAP hBitmapImag, hBitmapMask ;
static HINSTANCE hInstance ;
static int cxClient, cyClient, cxBitmap, cyBitmap ;
BITMAP bitmap ;
HDC hdc, hdcMemImag, hdcMemMask ;
int x, y, iVertPos, iHorzPos ,iMaxWidth=0;
SCROLLINFO si ;
PAINTSTRUCT ps ;
switch (message)
{
case WM_CREATE:
hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;
// Load the original image and get its size
hBitmapImag = LoadBitmap (hInstance, TEXT ("dongyun")) ;
GetObject (hBitmapImag, sizeof (BITMAP), &bitmap) ;
cxBitmap = bitmap.bmWidth ;
cyBitmap = bitmap.bmHeight ;
iMaxWidth=cxBitmap;
// Select the original image into a memory DC
hdcMemImag = CreateCompatibleDC (NULL) ;
SelectObject (hdcMemImag, hBitmapImag) ;
// Create the monochrome mask bitmap and memory DC
hBitmapMask = CreateBitmap (cxBitmap, cyBitmap, 1, 1, NULL) ;
hdcMemMask = CreateCompatibleDC (NULL) ;
SelectObject (hdcMemMask, hBitmapMask) ;
// Color the mask bitmap black with a white ellipse
SelectObject (hdcMemMask, GetStockObject (BLACK_BRUSH)) ;
Rectangle (hdcMemMask, 0, 0, cxBitmap, cyBitmap) ;
SelectObject (hdcMemMask, GetStockObject (WHITE_BRUSH)) ;
//Ellipse (hdcMemMask, 0, 0, cxBitmap, cyBitmap) ;
RoundRect(hdcMemMask,0,0,cxBitmap, cyBitmap,50, 50);
// Mask the original image
BitBlt (hdcMemImag, 0, 0, cxBitmap, cyBitmap,
hdcMemMask, 0, 0, SRCAND) ;
DeleteDC (hdcMemImag) ;
DeleteDC (hdcMemMask) ;
return 0 ;
case WM_SIZE:
cxClient = LOWORD (lParam) ;
cyClient = HIWORD (lParam) ;
// Set vertical scroll bar range and page size
si.cbSize = sizeof (si) ;
si.fMask = SIF_RANGE | SIF_PAGE ;
si.nMin = 0 ;
si.nMax =50*cyBitmap;
si.nPage = 50000*cyClient/cyBitmap;
SetScrollInfo (hwnd, SB_VERT, &si, TRUE) ;
// Set horizontal scroll bar range and page size
si.cbSize = sizeof (si) ;
si.fMask = SIF_RANGE | SIF_PAGE |SIF_DISABLENOSCROLL;
si.nMin = 0 ;
si.nMax =cxBitmap;
si.nPage = cxClient / 2;
SetScrollInfo (hwnd, SB_HORZ, &si, TRUE) ;
return 0 ;
case WM_VSCROLL:
// Get all the vertical scroll bar information
si.cbSize = sizeof (si) ;
si.fMask = SIF_ALL ;
GetScrollInfo (hwnd, SB_VERT, &si) ;
// Save the position for comparison later on
iVertPos = si.nPos ;
switch (LOWORD (wParam))
{
case SB_TOP:
si.nPos = si.nMin ;
break ;
case SB_BOTTOM:
si.nPos = si.nMax ;
break ;
case SB_LINEUP:
si.nPos -= 1000 ;
break ;
case SB_LINEDOWN:
si.nPos += 1000 ;
break ;
case SB_PAGEUP:
si.nPos -= si.nPage ;
break ;
case SB_PAGEDOWN:
si.nPos += si.nPage ;
break ;
case SB_THUMBPOSITION:
si.nPos = si.nTrackPos ;
break ;
default:
break ;
}
// Set the position and then retrieve it. Due to adjustments
// by Windows it may not be the same as the value set.
si.fMask = SIF_POS ;
SetScrollInfo (hwnd, SB_VERT, &si, TRUE) ;
GetScrollInfo (hwnd, SB_VERT, &si) ;
// If the position has changed, scroll the window and update it
if (si.nPos != iVertPos)
{
ScrollWindow (hwnd, 0, (cyClient - cyBitmap )* (iVertPos - si.nPos),
NULL, NULL) ;
UpdateWindow (hwnd) ;
}
return 0 ;
case WM_HSCROLL:
// Get all the vertical scroll bar information
si.cbSize = sizeof (si) ;
si.fMask = SIF_ALL ;
// Save the position for comparison later on
GetScrollInfo (hwnd, SB_HORZ, &si) ;
iHorzPos = si.nPos ;
switch (LOWORD (wParam))
{
case SB_LINELEFT:
si.nPos -= 1 ;
break ;
case SB_LINERIGHT:
si.nPos += 1 ;
break ;
case SB_PAGELEFT:
si.nPos -= si.nPage ;
break ;
case SB_PAGERIGHT:
si.nPos += si.nPage ;
break ;
case SB_THUMBPOSITION:
si.nPos = si.nTrackPos;
break ;
default :
break ;
}
// Set the position and then retrieve it. Due to adjustments
// by Windows it may not be the same as the value set.
si.fMask = SIF_POS ;
SetScrollInfo (hwnd, SB_HORZ, &si, TRUE) ;
GetScrollInfo (hwnd, SB_HORZ, &si) ;
// If the position has changed, scroll the window
if (si.nPos != iHorzPos)
{
ScrollWindow (hwnd, (cxClient - cxBitmap)*( iHorzPos - si.nPos), 0,
NULL, NULL) ;
}
return 0 ;
case WM_PAINT:
hdc = BeginPaint (hwnd, &ps) ;
si.cbSize = sizeof (si) ;
si.fMask = SIF_POS ;
GetScrollInfo (hwnd, SB_VERT, &si) ;
iVertPos = si.nPos ;
// Get horizontal scroll bar position
GetScrollInfo (hwnd, SB_HORZ, &si) ;
iHorzPos = si.nPos ;
// Select bitmaps into memory DCs
hdcMemImag = CreateCompatibleDC (hdc) ;
SelectObject (hdcMemImag, hBitmapImag) ;
hdcMemMask = CreateCompatibleDC (hdc) ;
SelectObject (hdcMemMask, hBitmapMask) ;
// Center image
x = (cxClient - cxBitmap- iHorzPos)/2 ;
y = (cyClient - cyBitmap- iVertPos)/64;
// Do the bitblts
BitBlt (hdc, x, y, cxBitmap, cyBitmap, hdcMemMask, 0, 0, 0x220326) ;
BitBlt (hdc, x, y, cxBitmap, cyBitmap, hdcMemImag, 0, 0, SRCPAINT) ;
DeleteDC (hdcMemImag) ;
DeleteDC (hdcMemMask) ;
EndPaint (hwnd, &ps) ;
return 0 ;
case WM_DESTROY:
DeleteObject (hBitmapImag) ;
DeleteObject (hBitmapMask) ;
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}
效果图：
