I'm creating a DIB Section in MFC using the call CreateDIBSection. I get a HBITMAP from the call which I pass onto another dialog in my MFC Project. In the other dialog I'm using CStatic::SetBitmap(HBITMAP) call to render the bitmap. But for some reason I'm not able to see anything. This works perfectly fine if this is done in same dialog, but I want to create bitmap in one dialog and display in another.
The code for creating the DIBSection is
//-----------------BEGINNING OF FIRST DIALOG--------------------------------------------------
LPVOID pViewBitmapBits = NULL;
BITMAPINFOHEADER BMHeaderInfo;
memset(&BMHeaderInfo, 0, sizeof(BITMAPINFOHEADER));
BMHeaderInfo.biSize = sizeof(BITMAPINFOHEADER);
BMHeaderInfo.biWidth = 800;
BMHeaderInfo.biHeight = 400;
BMHeaderInfo.biPlanes = 1;
BMHeaderInfo.biBitCount = 8;
BMHeaderInfo.biCompression = BI_RGB;
BMHeaderInfo.biSizeImage = 0;
BMHeaderInfo.biClrUsed = 0;
BMHeaderInfo.biClrImportant= 0;
BITMAPINFO BMInfo;
memset(&BMInfo, 0, sizeof(BMInfo));
BMInfo.bmiHeader = BMHeaderInfo;
BMInfo.bmiColors[0].rgbBlue=255;
HBITMAP hGlobalBitMap = CreateDIBSection(m_pParentSheet->test.m_hDC, &BMInfo, DIB_RGB_COLORS, &pViewBitmapBits, NULL, NULL);
SelectObject(m_pParentSheet->test.m_hDC, hGlobalBitMap);
//--------------------------END OF FIRST DIALOG----------------------------------
//-----------------------------BEGINNING OF SECOND DIALOG----------------------------------------
void CreateViewDlg::OnBnClickedButton2()
{
m_pic.SetBitmap(hGlobalBitMap );
}
//------------------------------------END OF SECOND DIALOG---------------------------------
Please help me with this. Is there any limitation to the usage of HBITMAP Handles?
HBITMAP hGlobalBitMap = ...
Looks like local variable hiding the global variable.
Related
I need your help for a project at my job.
The main software, using 4D language, works as a MDI, it creates many windows included in the main window. The main issue is that we have a lot of windows and we need an easy way to switch from a window to another.
We decided to create a little c++ plugin which is a dll to resolve this issue.
This plugin will create a tab on the taskbar for each window opened like Windows Explorer. The creation and the deletion of tabs already works.
But the current problem is that no thumbnail is set on the Tab.
The parameter given is the ID of the window from the main software. The method called PA_GetHWND is the method given by 4D to obtain the handle of the window using the windowID.
I have already check where is the problem. The bitmap created from the window already exists and is good. For this test, i put the bitmap in the clipboard and paste it on Paint and the Bitmap was good.
Here is the code introducing the method to refresh the bitmap on the tab.
bool CManageTaskBar::UpdateWindow(long WindowID)
{
HRESULT res;
HDC hdcScreen;
HDC hdcWindow;
HDC hdcMemDC = NULL;
HBITMAP hbmScreen = NULL;
//Get the Handle from 4D
HWND nHandle = (HWND)(PA_GetHWND((PA_WindowRef)(WindowID)));
// Retrieve the handle to a display device context for the client
// area of the window.
hdcScreen = GetDC(NULL);
hdcWindow = GetDC(nHandle);
// Create a compatible DC which is used in a BitBlt from the window DC
hdcMemDC = CreateCompatibleDC(hdcWindow);
// Get the client area for size calculation
RECT rcClient;
GetClientRect(nHandle, &rcClient);
// Create a compatible bitmap from the Window DC
hbmScreen = CreateCompatibleBitmap(hdcWindow,rcClient.right - rcClient.left, rcClient.bottom - rcClient.top);
// Select the compatible bitmap into the compatible memory DC.
SelectObject(hdcMemDC, hbmScreen);
// Bit block transfer into our compatible memory DC.
if (!BitBlt(hdcMemDC,
0, 0,
rcClient.right - rcClient.left, rcClient.bottom - rcClient.top,
hdcWindow,
0, 0,
SRCCOPY))
{
MessageBox(nHandle, L"BitBlt has failed", L"Failed", MB_OK);
//goto done;
}
ITaskbarList3* ptbl = NULL;
HRESULT hr = CoCreateInstance(my_CLSID_TaskbarList, NULL, CLSCTX_ALL, my_IID_ITaskbarList3, (LPVOID*)&ptbl);
BOOL fForceIconic = TRUE;
BOOL fHasIconic = TRUE;
res = DwmSetWindowAttribute(nHandle, DWMWA_FORCE_ICONIC_REPRESENTATION, &fForceIconic, sizeof(fForceIconic));
res = DwmSetWindowAttribute(nHandle, DWMWA_HAS_ICONIC_BITMAP, &fHasIconic, sizeof(fHasIconic));
if (hbmScreen)
{
res = DwmSetIconicThumbnail(nHandle, hbmScreen,0);//DWM_SIT_DISPLAYFRAME);
}
DeleteObject(hbmScreen);
DeleteObject(hdcMemDC);
ReleaseDC(NULL, hdcScreen);
ReleaseDC(nHandle, hdcWindow);
return true;
}
The calls to DwmSetWindowAttribute return Invalid Handle. This handle works to get a bitmap but not to set an attribute.
And the call to DwmSetIconicThumbnail returns E_INVALIDARG maybe because the handle given is wrong.
Why cannot I set an attribute to this handle and why the call to set the thumbnail returns E_INVALIDARG ?
Thanks to everyone who will take care of my problem.
It's my first question, be friendly please :)
I would like to create 32 bit color icons programmatically using C++ and Win API. For this purpose I use the following code which I found here.
HICON CreateSolidColorIcon(COLORREF iconColor, int width, int height)
{
// Obtain a handle to the screen device context.
HDC hdcScreen = GetDC(NULL);
// Create a memory device context, which we will draw into.
HDC hdcMem = CreateCompatibleDC(hdcScreen);
// Create the bitmap, and select it into the device context for drawing.
HBITMAP hbmp = CreateCompatibleBitmap(hdcScreen, width, height);
HBITMAP hbmpOld = (HBITMAP)SelectObject(hdcMem, hbmp);
// Draw your icon.
//
// For this simple example, we're just drawing a solid color rectangle
// in the specified color with the specified dimensions.
HPEN hpen = CreatePen(PS_SOLID, 1, iconColor);
HPEN hpenOld = (HPEN)SelectObject(hdcMem, hpen);
HBRUSH hbrush = CreateSolidBrush(iconColor);
HBRUSH hbrushOld = (HBRUSH)SelectObject(hdcMem, hbrush);
Rectangle(hdcMem, 0, 0, width, height);
SelectObject(hdcMem, hbrushOld);
SelectObject(hdcMem, hpenOld);
DeleteObject(hbrush);
DeleteObject(hpen);
// Create an icon from the bitmap.
//
// Icons require masks to indicate transparent and opaque areas. Since this
// simple example has no transparent areas, we use a fully opaque mask.
HBITMAP hbmpMask = CreateCompatibleBitmap(hdcScreen, width, height);
ICONINFO ii;
ii.fIcon = TRUE;
ii.hbmMask = hbmpMask;
ii.hbmColor = hbmp;
HICON hIcon = CreateIconIndirect(&ii);
DeleteObject(hbmpMask);
// Clean-up.
SelectObject(hdcMem, hbmpOld);
DeleteObject(hbmp);
DeleteDC(hdcMem);
ReleaseDC(NULL, hdcScreen);
// Return the icon.
return hIcon;
}
In principle the code works and I can use it to create colored icons at runtime using the Win API. However, I have some problems and questions about that code (and creating icons in general) which I would like to discuss.
The icons created with this function don't seem to be of 32 bit color depth. If I use a color like RGB(218, 112, 214) I would expect it to be some light purple. However, the actual displayed color is gray. How can I change the code such that the color is really 32 bit RGB?
The icon created is completly filled with the color, I would like to have a thin black boarder around it... how can this be achieved?
In the MSDN documentation (a bit downwards) it is mentioned that "Before closing, your application must use DestroyIcon to destroy any icon it created by using CreateIconIndirect. It is not necessary to destroy icons created by other functions. " However, in the documentation for e.g. CreateIcon in MSDN it is said that "When you are finished using the icon, destroy it using the DestroyIcon function." which is pretty much a contradiction. When do I actually have to destroy the icon?
Do these rules then also apply when I add the icon to an image list and this list to a combobox? I.e. do I have to clean up the image list and each associated icon?
Any help is highly appreciated.
When do I actually have to destroy the icon?
read about DestroyIcon
It is only necessary to call DestroyIcon for icons and cursors
created with the following functions: CreateIconFromResourceEx (if
called without the LR_SHARED flag), CreateIconIndirect, and
CopyIcon. Do not use this function to destroy a shared icon. A
shared icon is valid as long as the module from which it was loaded
remains in memory. The following functions obtain a shared icon.
LoadIcon
LoadImage (if you use the LR_SHARED flag)
CopyImage (if you use the LR_COPYRETURNORG flag and the hImage parameter is a shared icon)
CreateIconFromResource
CreateIconFromResourceEx (if you use the LR_SHARED flag)
so you need call DestroyIcon for not shared icon, when you are finished using it
ComboBoxEx not destroy image list which you assign to it with CBEM_SETIMAGELIST - so this image list must be valid until ComboBoxEx valid and you must destroy it yourself later.
ImageList_AddIcon
Because the system does not save hicon, you can destroy it after the
macro returns
in other words ImageList_AddIcon make copy of your icon, and you can destroy your original icon, after macro return
for create 32 bit color icon try code like this:
HICON CreateGradientColorIcon(COLORREF iconColor, int width, int height)
{
HICON hIcon = 0;
ICONINFO ii = { TRUE };
ULONG n = width * height;
if (PULONG lpBits = new ULONG[n])
{
PULONG p = lpBits;
ULONG x, y = height, t;
do
{
x = width, t = --y << 8;
do
{
*p++ = iconColor | ((t * --x) / n << 24);
} while (x);
} while (y);
if (ii.hbmColor = CreateBitmap(width, height, 1, 32, lpBits))
{
if (ii.hbmMask = CreateBitmap(width, height, 1, 1, 0))
{
hIcon = CreateIconIndirect(&ii);
DeleteObject(ii.hbmMask);
}
DeleteObject(ii.hbmColor);
}
delete [] lpBits;
}
return hIcon;
}
when I draw (DrawIconEx(, DI_IMAGE|DI_MASK)) this icon over green mesh I view next:
To everyone who has stumbled upon this solution, I am simply posting a little bit more of a documented solution to RbMm's answer. This is basically the same as his solution (maybe not as performant, I'm not sure):
static HICON CreateIconFromBytes(HDC DC, int width, int height, uint32* bytes) {
HICON hIcon = NULL;
ICONINFO iconInfo = {
TRUE, // fIcon, set to true if this is an icon, set to false if this is a cursor
NULL, // xHotspot, set to null for icons
NULL, // yHotspot, set to null for icons
NULL, // Monochrome bitmap mask, set to null initially
NULL // Color bitmap mask, set to null initially
};
uint32* rawBitmap = new uint32[width * height];
ULONG uWidth = (ULONG)width;
ULONG uHeight = (ULONG)height;
uint32* bitmapPtr = rawBitmap;
for (ULONG y = 0; y < uHeight; y++) {
for (ULONG x = 0; x < uWidth; x++) {
// Bytes are expected to be in RGB order (8 bits each)
// Swap G and B bytes, so that it is in BGR order for windows
uint32 byte = bytes[x + y * width];
uint8 A = (byte & 0xff000000) >> 24;
uint8 R = (byte & 0xff0000) >> 16;
uint8 G = (byte & 0xff00) >> 8;
uint8 B = (byte & 0xff);
*bitmapPtr = (A << 24) | (R << 16) | (G << 8) | B;
bitmapPtr++;
}
}
iconInfo.hbmColor = CreateBitmap(width, height, 1, 32, rawBitmap);
if (iconInfo.hbmColor) {
iconInfo.hbmMask = CreateCompatibleBitmap(DC, width, height);
if (iconInfo.hbmMask) {
hIcon = CreateIconIndirect(&iconInfo);
if (hIcon == NULL) {
Log::Warning("Failed to create icon.");
}
DeleteObject(iconInfo.hbmMask);
} else {
Log::Warning("Failed to create color mask.");
}
DeleteObject(iconInfo.hbmColor);
} else {
Log::Warning("Failed to create bitmap mask.");
}
delete[] rawBitmap;
return hIcon;
}
This solution will work with STB image library for loading images. So you can literally just load an image with stb, then pass the byte data to this function, and you will get an icon as a result. I had a little bit of trouble setting the icon as well, and eventually did this to get that to work:
HICON icon = CreateIconFromBytes(DC, image.m_Width, image.m_Height, image.m_Pixels);
SendMessage(WND, WM_SETICON, ICON_SMALL, (LPARAM)icon);
SendMessage(WND, WM_SETICON, ICON_BIG, (LPARAM)icon);
SendMessage(WND, WM_SETICON, ICON_SMALL2, (LPARAM)icon);
The only thing you should note about this is that you should probably use 3 different sized icons for the SendMessage() functions, but other than that this worked good for me :)
Edit:
Here's the links to official MSDN documentation as well.
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-createiconindirect
https://learn.microsoft.com/en-us/windows/win32/api/wingdi/nf-wingdi-createbitmap
https://learn.microsoft.com/en-us/windows/win32/api/wingdi/nf-wingdi-createcompatiblebitmap
https://learn.microsoft.com/en-us/windows/win32/menurc/using-icons
I'm trying to use StretchBlt in order to copy pixels from a memory hdc to the window hdc.
The memory hdc gets the image from an invisible window which renders a stream using openGL.
Here's my code:
BITMAPINFOHEADER createBitmapHeader(int width, int height) {
BITMAPINFOHEADER header;
header.biSize = sizeof(BITMAPINFOHEADER);
header.biWidth = width;
header.biHeight = height;
header.biPlanes = 1;
header.biBitCount = 32;
header.biCompression = BI_RGB;
header.biSizeImage = 0;
header.biXPelsPerMeter = 0;
header.biYPelsPerMeter = 0;
header.biClrUsed = 0;
header.biClrImportant = 0;
return header;
}
...
HDC memoryHdc = CreateCompatibleDC(windowHdc);
BITMAPINFO bitmapInfo;
bitmapInfo.bmiHeader = createBitmapHeader(targetDimensions.width, targetDimensions.height);
HBITMAP bitmap = CreateDIBitmap(windowHdc, &bitmapInfo.bmiHeader, CBM_INIT, offscreenBuffer, &bitmapInfo, DIB_RGB_COLORS);
SelectObject(memoryHdc, bitmap);
DeleteObject(bitmap);
SetStretchBltMode(windowHdc, COLORONCOLOR);
StretchBlt(windowHdc,
targetDimensions.x, targetDimensions.y,
targetDimensions.width, -targetDimensions.height,
memoryHdc,
sourceDimensions.x, sourceDimensions.y,
sourceDimensions.width, sourceDimensions.height,
SRCCOPY);
DeleteDC(memoryHdc);
Where windowHdc is the hdc of the window to which I want the StretchBlt to copy the pixels to, and offscreenBuffer is a void* to the pixels copied from the offscreen window in which the openGL is rendering.
This code works great, except that the image is upside down and I want it vertically flipped.
I know that this happens because:
If nHeightSrc and nHeightDest have different signs, the function
creates a mirror image of the bitmap along the y-axis
But when I remove the minus sign and both target and source heights are the same then I see no image in the window.
Just to check, I tried to put the minus on the sourceDimensions.height but that also results in no image, and the same if I try to negate the widths (both target and source).
Any idea why?
Thanks.
I've googled, seen examples, other questions here, MSDN and Downloaded Example code. I cannot figure out what is wrong with this.
// setting up the memory DC and selecting in the bitmap
HDC hdc = GetDC(hWnd);
HDC hdcMem = CreateCompatibleDC(hdc);
ReleaseDC(hWnd, hdc);
HBITMAP hbmOld = (HBITMAP)SelectObject(hdcMem, bitmap.hbmLogo);
// setting up the blend function
BLENDFUNCTION bStruct;
bStruct.BlendOp = AC_SRC_OVER;
bStruct.BlendFlags = 0;
bStruct.SourceConstantAlpha = 255;
bStruct.AlphaFormat = AC_SRC_ALPHA;
// try
BOOL check = AlphaBlend(buffer.getBufferDC(), 0, 0, bitmap.bmLogo.bmWidth, bitmap.bmLogo.bmHeight, hdcMem, 0, 0, bitmap.bmLogo.bmWidth, bitmap.bmLogo.bmHeight, bStruct);
if (check == FALSE) MessageBox(0,0,0,0);
// this is how I load the bitmap, it is a resource.
bitmap.hbmLogo = LoadBitmap(GetModuleHandle(NULL), MAKEINTRESOURCE(IDB_LOGO_0));
if (bitmap.hbmLogo == NULL) { MessageBox(NULL, "Could not read the logo bitmap.", "Error", MB_OK); return false; }
GetObject(bitmap.hbmLogo, sizeof(bitmap.bmLogo), &bitmap.bmLogo);
I use the message box to quickly check the result. Check always returns TRUE. The bitmap and its dimensions are correct.
I've tried it over different background colors, alpha values, and still nothing, replacing that with BitBlt or TransparentBitBlt, no problem, the logo displays. All my attempts with the AlphaBlend function has resulted in no change. The logo does not appear, even for a second, on the screen.
Any ideas?
Thanks.
Found the solution after looking closer at an example.
I set the BLENDFUNCTION as a global, and in the WM_CREATE message I used:
m_bf.BlendOp = AC_SRC_OVER;
m_bf.BlendFlags = 0;
m_bf.SourceConstantAlpha = 100; // any 0 to 255
m_bf.AlphaFormat = 0;
LoadBitmapsFromResource();
and it is now working.
was using XP without issue for a long time. switched to 7 and trying to capture screenshots with my previously functioning code no longer works. simple concept and relatively generic code...just find the window that i call and save it as a .png. any ideas what might make this bad boy run again? can't debug with my current setup, but it makes it all the way and spits out the error message after bmp->save(...) ...couldn't save image file. edit: also a file does get created/saved, but it is blank and not written to. perhaps the bitmap encoding or GDI is screwed up?
bool CScreenShot::Snap(CString wintitle, CString file, CString& ermsg)
{
ermsg = ""; // no error message
// create screen shot bitmap
EnumWinProcStruct prm = {0, (LPSTR)(LPCTSTR)wintitle, 0};
// Find the descriptor of the window with the caption wintitle
EnumDesktopWindows(0, EnumWindowsProc, (LPARAM)&prm);
if(!prm.hwnd)
{
ermsg.Format("couldn't find window \"%s\"", wintitle);
return false;
}
// Make the window the topmost window
SetWindowPos(prm.hwnd, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE);
Sleep(300);
// Get device context for the top-level window and client rect
HDC hDC = GetDC(prm.hwnd);
RECT rc;
GetClientRect(prm.hwnd, &rc);
HDC memDC = CreateCompatibleDC(hDC);
// Set the size and color depth for the screen shot image
BITMAPINFO bmpInfo;
memset(&bmpInfo, 0, sizeof(bmpInfo));
bmpInfo.bmiHeader.biSize = sizeof(bmpInfo.bmiHeader);
bmpInfo.bmiHeader.biWidth = rc.right - rc.left;
bmpInfo.bmiHeader.biHeight = rc.bottom - rc.top;
bmpInfo.bmiHeader.biPlanes = 1;
bmpInfo.bmiHeader.biBitCount = 24;
bmpInfo.bmiHeader.biCompression = BI_RGB;
bmpInfo.bmiHeader.biSizeImage = bmpInfo.bmiHeader.biWidth * bmpInfo.bmiHeader.biHeight * 3;
// Create memory buffer and perform a bit-block transfer of the color data from the window to the memory
LPVOID addr;
HBITMAP memBM = CreateDIBSection(memDC, &bmpInfo, DIB_RGB_COLORS, &addr, 0, 0);
HGDIOBJ stdBM = SelectObject(memDC, memBM);
BOOL OK = BitBlt(memDC, 0, 0, bmpInfo.bmiHeader.biWidth, bmpInfo.bmiHeader.biHeight, hDC, 0, 0, SRCCOPY);
ReleaseDC(prm.hwnd, hDC);
SetWindowPos(prm.hwnd, HWND_NOTOPMOST, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE);
// Initialize GDI+.
GdiplusStartupInput gdiplusStartupInput;
ULONG_PTR gdiplusToken;
if(GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL) != Ok)
{
ermsg.Format("couldn't start GDI+");
return false;
}
// Create a Bitmap object for work with images defined by pixel data from the GDI HBitmap and the GDI HPalette.
Bitmap* bmp = ::new Bitmap(memBM, DIB_RGB_COLORS);
SelectObject(memDC, stdBM);
DeleteObject(memBM);
DeleteDC(memDC);
// Find the encoder for "image/png" mime type
CLSID encoderClsid;
EncoderParameters encoderParameters;
GetEncoderClsid(L"image/png", &encoderClsid);
encoderParameters.Count = 0;
// Convert file name to Unicode (wide-char) string.
WCHAR fn[_MAX_PATH];
MultiByteToWideChar(CP_THREAD_ACP, MB_PRECOMPOSED, file, file.GetLength() + 1, fn, _MAX_PATH);
// Save the screen shot into the specified file using image encoder with the mime style "image/png"
if(bmp->Save(fn, &encoderClsid, &encoderParameters) != Ok)
{
ermsg.Format("couldn't save image file \"%s\"", file);
return false;
}
::delete bmp;
GdiplusShutdown(gdiplusToken);
return true;
}
The error message implies that you're trying to save the file to a folder that you don't have permission to write to. Many folders such as Program Files are now protected. Since you didn't include the path in your sample code I'm unable to determine if this is the actual problem.
Edit: Another possibility is that the Bitmap is improperly constructed which causes the Save to fail. The second parameter to the constructor is supposed to be a handle to a palette, I think DIB_RGB_COLORS would be invalid here and you should use NULL. Also there are a couple of caveats noted in the Microsoft documentation and perhaps the different OS versions react differently when you break the rules:
You are responsible for deleting the GDI bitmap and the GDI palette. However, you should not delete the GDI bitmap or the GDI palette until after the GDI+ Bitmap::Bitmap object is deleted or goes out of scope.
Do not pass to the GDI+ Bitmap::Bitmap constructor a GDI bitmap or a GDI palette that is currently (or was previously) selected into a device context.
win7 won't accept encoderParameters.Count == 0 for some reason. Set that == 1 and you should be all set.
you probably could also just remove that parameter from Save() (overloaded)