经验证,图片保存部分代码没有问题,问题好像处在了读取数据的部分,但是始终看不出错误在哪?请大家多多指教!部分代码如下:
g_width=r-l;
g_height=t-b; FILE* pDummyFile;
FILE* pWritingFile;
GLubyte* pPixelData;
GLubyte BMP_Header[54];
GLint i, j;
GLint PixelDataLength;
// 计算像素数据的实际长度
i = g_width * 3; // 得到每一行的像素数据长度
while( i%4 != 0 )
++i;
PixelDataLength = i * g_height;
// 分配内存和打开文件
pPixelData = (GLubyte*)malloc(PixelDataLength);
if( pPixelData == 0 )
exit(0);
pDummyFile = fopen("dummy.bmp", "rb");
if( pDummyFile == 0 )
exit(0);
pWritingFile = fopen("grab.bmp", "wb");
if( pWritingFile == 0 )
exit(0);
// 读取像素
glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
glReadPixels(0, 0, g_width, g_height, GL_BGR_EXT, GL_UNSIGNED_BYTE, pPixelData);
// 把dummy.bmp的文件头复制为新文件的文件头
fread(BMP_Header, sizeof(BMP_Header), 1, pDummyFile);
fwrite(BMP_Header, sizeof(BMP_Header), 1, pWritingFile);
fseek(pWritingFile, 0x0012, SEEK_SET);
i = g_width;
j = g_height;
fwrite(&i, sizeof(i), 1, pWritingFile);
fwrite(&j, sizeof(j), 1, pWritingFile);
// 写入像素数据
fseek(pWritingFile, 0, SEEK_END);
fwrite(pPixelData, PixelDataLength, 1, pWritingFile);
// 释放内存和关闭文件
fclose(pDummyFile);
fclose(pWritingFile);
free(pPixelData);
g_width=r-l;
g_height=t-b; FILE* pDummyFile;
FILE* pWritingFile;
GLubyte* pPixelData;
GLubyte BMP_Header[54];
GLint i, j;
GLint PixelDataLength;
// 计算像素数据的实际长度
i = g_width * 3; // 得到每一行的像素数据长度
while( i%4 != 0 )
++i;
PixelDataLength = i * g_height;
// 分配内存和打开文件
pPixelData = (GLubyte*)malloc(PixelDataLength);
if( pPixelData == 0 )
exit(0);
pDummyFile = fopen("dummy.bmp", "rb");
if( pDummyFile == 0 )
exit(0);
pWritingFile = fopen("grab.bmp", "wb");
if( pWritingFile == 0 )
exit(0);
// 读取像素
glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
glReadPixels(0, 0, g_width, g_height, GL_BGR_EXT, GL_UNSIGNED_BYTE, pPixelData);
// 把dummy.bmp的文件头复制为新文件的文件头
fread(BMP_Header, sizeof(BMP_Header), 1, pDummyFile);
fwrite(BMP_Header, sizeof(BMP_Header), 1, pWritingFile);
fseek(pWritingFile, 0x0012, SEEK_SET);
i = g_width;
j = g_height;
fwrite(&i, sizeof(i), 1, pWritingFile);
fwrite(&j, sizeof(j), 1, pWritingFile);
// 写入像素数据
fseek(pWritingFile, 0, SEEK_END);
fwrite(pPixelData, PixelDataLength, 1, pWritingFile);
// 释放内存和关闭文件
fclose(pDummyFile);
fclose(pWritingFile);
free(pPixelData);
你可以看看这篇文章
CPaintDC dc(this);
CDC memDC;
CRect rect;
GetClientRect(rect); memDC.CreateCompatibleDC(&SHDC);
CBitmap bm;
int Width = rect.Width();//
int Height = rect.Height();//
bm.CreateCompatibleBitmap(&SHDC, Width, Height);
CBitmap* pOld = memDC.SelectObject(&bm);
memDC.BitBlt(0, 0, Width, Height, &SHDC, 0, 0, SRCCOPY);
memDC.SelectObject(pOld);
BITMAP btm;
bm.GetBitmap(&btm);
DWORD size = btm.bmWidthBytes * btm.bmHeight;
LPSTR lpData =(LPSTR)GlobalAllocPtr(GPTR, size);
BITMAPFILEHEADER bfh;
/////////////////////////////////////////////
BITMAPINFOHEADER bih;
bih.biBitCount = btm.bmBitsPixel;
bih.biClrImportant = 0;
bih.biClrUsed = 0;
bih.biCompression = 0;
bih.biHeight = btm.bmHeight;
bih.biPlanes = 1;
bih.biSize = sizeof(BITMAPINFOHEADER);
bih.biSizeImage = size;
bih.biWidth = btm.bmWidth;
bih.biXPelsPerMeter = 0;
bih.biYPelsPerMeter = 0;
GetDIBits(dc,bm,0,bih.biHeight,lpData,(BITMAPINFO*)&bih,DIB_RGB_COLORS);
bfh.bfReserved1 = bfh.bfReserved2 = 0;
bfh.bfType = ((WORD)('M'<< 8)|'B');
bfh.bfSize = 54 + size;
bfh.bfOffBits = 54; CFileDialog dlg(false,_T("BMP"),_T("*.bmp"),OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,_T("*.bmp|*.bmp|*.*|*.*|"));
if (dlg.DoModal()==IDOK)
{
CFile bf;
CString ss=dlg.GetPathName();
if(bf.Open(ss, CFile::modeCreate | CFile::modeWrite))
{
bf.WriteHuge(&bfh, sizeof(BITMAPFILEHEADER));
bf.WriteHuge(&bih, sizeof(BITMAPINFOHEADER));
bf.WriteHuge(lpData, size);
bf.Close();
}
GlobalFreePtr(lpData);
}上面是保存的代码,但不是opengl的