I'm writing a c++ console program for Windows using the windows.h include.
I've been trying to tailor the console size to fit my program output, but without finding a reliable way to obtain the value for width and height of a "cell" (the character boxes). I've tried both GetConsoleFontSize and GetConsoleScreenBufferInfo + GetDesktopWindow as demonstrated in the code sample below.
HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
CONSOLE_FONT_INFO font_size;
GetConsoleFontSize(hOut,GetCurrentConsoleFont(hOut, false, &font_size));
CONSOLE_SCREEN_BUFFER_INFO csbi;
GetConsoleScreenBufferInfo(hOut, &csbi);
RECT desktop;
// Get a handle to the desktop window
const HWND hDesktop = GetDesktopWindow();
// Get the size of screen to the variable desktop
GetWindowRect(hDesktop, &desktop);
// Calculate size of one cell in the console, expressed in pixels.
COORD cell;
// Screen width/max number of columns
cell.X = desktop.right/ csbi.dwMaximumWindowSize.X;
// Screen height/max number of rows
cell.Y = desktop.bottom / csbi.dwMaximumWindowSize.Y;
// Change console size
HWND console = GetConsoleWindow();
MoveWindow(console, 0, 0, 10 * cell.X * 2, 10 * cell.Y, TRUE);
MoveWindow(console, 0, 0, 10 * font_size.dwFontSize.X * 2, 10 * font_size.dwFontSize.Y, TRUE);
Of both attempts I expected a square window able to contain just about 20x10 cells (the height of the cells seem to be 2x the width), with some margin of error on one of the examples given the integer division. However, they both seemed to be approximately 25% too small, apart from the width of the first example with is about 10% too large.
I assume that the font size does not include the spacing between letters and that the dependencies of .dwMaxWindowSize (such as buffer size etc) comes into play, but I can't quite get either method straight.
If anyone has any knowledge of how to obtain the width/height of the cells in pixels reliably I'd be very grateful. Any information regarding what goes into the cells, what affects the return value of either function or other functions I can use to achieve my goal.
Also note that the size is ultimately going to be bigger, but since I wanted to manually count the rows/columns to debug I made it smaller.
I almost have a solution now, but it still needs some work.
CONSOLE_SCREEN_BUFFER_INFO csbi;
HWND console = GetConsoleWindow();
// Resolution
RECT newClientSize, oldClientSize, newWindowSize, oldWindowSize;
// Colums, Rows
COORD newBuffer{20,50}, oldBuffer;
for (int i = 0; i < 2; i++) {
// Calculate the starting amount of columns and rows.
GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi);
oldBuffer.X = csbi.srWindow.Right - csbi.srWindow.Left + 1;
oldBuffer.Y = csbi.srWindow.Bottom - csbi.srWindow.Top + 1;
printf("%i\n", oldBuffer.X);
printf("%i\n", oldBuffer.Y);
// Get size of client area
GetClientRect(console, &oldClientSize);
newClientSize.right = oldClientSize.right * newBuffer.X / oldBuffer.X;
newClientSize.bottom = oldClientSize.bottom * newBuffer.Y / oldBuffer.Y;
// Get size of window area
GetWindowRect(console, &oldWindowSize);
newWindowSize.right = newClientSize.right + oldWindowSize.right - oldClientSize.right;
newWindowSize.bottom = newClientSize.bottom + oldWindowSize.bottom - oldClientSize.bottom;
MoveWindow(console, 0, 0, newWindowSize.right, newWindowSize.bottom, TRUE);
}
GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi);
oldBuffer.X = csbi.srWindow.Right - csbi.srWindow.Left + 1;
oldBuffer.Y = csbi.srWindow.Bottom - csbi.srWindow.Top + 1;
printf("%i\n", oldBuffer.X);
printf("%i\n", oldBuffer.Y);
What I don't understand is why it works when I repeat the code two or more times. The only thing I don't think I fully understand is
the different between ClientRect and WindowRect. However, as always, there's a possibility that there's something else I'm missing.
I have an MFC dialog window where I added a WebBrowser control (that encapsulates the Internet Explorer engine.)
The goal of the following code is to render the contents of the said web browser control into a device context that I can later use for printing:
//MFC code, error checks are omitted for brevity
//'m_browser' = is a web browser control of type `CExplorer1`
IDispatch* pHtmlDoc = m_browser.get_Document();
CComPtr<IHTMLDocument2> pHtmlDocument2;
pHtmlDoc->QueryInterface(IID_IHTMLDocument2, (void**)&pHtmlDocument2));
//Get IViewObject2 for the entire document that we will use to render into a DC
CComPtr<IViewObject2> pViewObject;
pHtmlDocument2->QueryInterface(IID_IViewObject2, (void **)&pViewObject));
CComPtr<IHTMLElement> pBody;
pHtmlDocument2->get_body(&pBody));
CComPtr<IHTMLElement2> pBody2;
pBody->QueryInterface(IID_IHTMLElement2, (void **)&pBody2));
//Get default printer DC
CPrintDialog pd(TRUE, PD_ALLPAGES | PD_USEDEVMODECOPIES | PD_NOPAGENUMS | PD_HIDEPRINTTOFILE | PD_NOSELECTION);
pd.m_pd.Flags |= PD_RETURNDC | PD_RETURNDEFAULT;
pd.DoModal(); //corrected later
HDC hPrintDC = pd.CreatePrinterDC();
//Calc bitmap width based on printer DC specs
//Note that this width will be larger than
//the width of the WebControl window itself due to
//printer's much higher DPI setting...
int n_bitmapWidth = ::GetDeviceCaps(hPrintDC, HORZRES); //Use entire printable area
//Get full size of the document
long n_scrollWidth;
long n_scrollHeight;
pBody2->get_scrollWidth(&n_scrollWidth);
pBody2->get_scrollHeight(&n_scrollHeight);
//Calc proportional size of the bitmap in the DC to render
int nWidth = n_bitmapWidth;
int nHeight = n_bitmapWidth * n_scrollHeight / n_scrollWidth;
//Create memory DC to render into
HDC hDc = ::GetDC(hWnd);
HDC hCompDc = ::CreateCompatibleDC(hDC);
//I'm using a raw DIB section here as I'll need to access
//its bitmap bits directly later in my code...
BITMAPINFOHEADER infoHeader = {0};
infoHeader.biSize = sizeof(infoHeader);
infoHeader.biWidth = nWidth;
infoHeader.biHeight = -nHeight;
infoHeader.biPlanes = 1;
infoHeader.biBitCount = 24;
infoHeader.biCompression = BI_RGB;
BITMAPINFO info;
info.bmiHeader = infoHeader;
//Create a bitmap as DIB section of size `nWidth` by `nHeight` pixels
BYTE* pMemory = 0;
HBITMAP hBitmap = ::CreateDIBSection(hDc, &info, DIB_RGB_COLORS, (void**)&pMemory, 0, 0);
HBITMAP hOldBmp = (HBITMAP)::SelectObject(hCompDc, hBitmap);
RECT rcAll = {0, 0, nWidth, nHeight};
::FillRect(hCompDc, &rcAll, (HBRUSH)::GetStockObject(WHITE_BRUSH));
RECTL rectPrnt = {0, 0, nWidth, nHeight};
//Do the upscaling & render -- note that IE8 fails to render it here!!!!
pViewObject->Draw(DVASPECT_CONTENT, //DVASPECT_DOCPRINT
-1, NULL, NULL, NULL, hCompDc,
&rectPrnt,
NULL,
NULL, 0));
::SelectObject(hCompDc, hOldBmp);
//Now the bitmap in `hCompDc` contains the resulting pixels
//For debugging purposes, save it as .bmp file
BITMAPFILEHEADER fileHeader = {0};
fileHeader.bfType = 0x4d42;
fileHeader.bfSize = 0;
fileHeader.bfReserved1 = 0;
fileHeader.bfReserved2 = 0;
fileHeader.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
CFile file(
L"path-to\\test.bmp",
CFile::modeCreate | CFile::modeReadWrite | CFile::shareDenyNone);
file.Write((char*)&fileHeader, sizeof(fileHeader));
file.Write((char*)&infoHeader, sizeof(infoHeader));
int bytes = (((24 * nWidth + 31) & (~31)) / 8) * nHeight;
file.Write(pMemory, bytes);
//Clean up
::DeleteObject(hBitmap);
::DeleteDC(hCompDc);
::ReleaseDC(hWnd, hDc);
::DeleteDC(hPrintDC);
This code works fine if I have the latest IE11 installed on my development machine. But if, for instance, someone has IE8 installed on their Windows 7, the IViewObject::Draw method will render only a small part of the document (equal to the size of the web browser control itself.)
The best way to describe it is to illustrate it with the examples:
Normally rendered test page with IE11 installed:
and here's what happens with IE8 installed:
Does anyone have any idea what am I doing wrong here that IE8 doesn't like?
EDIT1: Did some more digging into the IViewObject::Draw function with WinDbg and then found the source code for it. Here's CServer::Draw() that is IViewObject::Draw, and then CDoc::Draw() that is called internally from CServer::Draw().
First, thanks for the interesting question. While not so practical - not a lot of people use IE8 today - it was not so trivial to solve. I'll describe what is the problem and provide a simplistic but working solution that you can improve.
Before I go into IE8 solution, a couple of points:
The solution with window resize to fit scroll size is not stable if you can encounter large documents. If you don't know what to anticipate, you need to refactor the solution for later explorers as well, to avoid relying on resizing window to scroll size.
Why carry giant bitmap? Metafiles etc. may fit better. Any large enough page at this resolution is going to blow memory on PC with the naive DIB creation. Google page in provided sample renders to 100Mb bitmap file while emf, from which rasterization is done, takes less than 1Mb.
While I don't know exact requirements and limitations of your project, I'm 99% sure that drawing into gigantic DIB is not the best solution. Even EMF, while better, is not the best either. If you need, for example, add a signature and then print, there are better ways to handle this. This, of course, just a side note, not related to the question itself.
IE8 rendering problem
In IE8 renderer there is a bug. Draw() will be clipped at pixel dimensions of actual display area (the visible rectangle you see is the original display area in the scale of rendering context).
So, if you have a scaled target that is larger than the actual size, while scaled, it will be clipped to the size in scaled pixels anyway (so it has much less content than original rectangle).
If it doesn't clip for somebody on genuine IE8, then there are remainders of later IE in the system or there is other non-scratch setup, system update or alike.
Workaround possibilities
Good news it is possible to workaround, bad news workarounds are a bit nasty.
First, it is still possible to workaround with IViewObject. But, because there is arbitrary scaling involved and accessible source rectangle is very small, this solution has some complexities that I think are beyong an SO answer. So I would not dive into this path.
Instead, we can render through another, now outdated API: IHTMLElementRender. It allows to render the page with DrawToDC into arbitrary context. Unfortunately, it is not so simple as it may appear and goes beyond just providing device context.
First, there is similar bug of clipping. It can be handled easier because clipping occurs at large values beyond screen dimensions. Second, when using device context transformations it either will not work or will mess the rendered html, so you can't actually rely on scale or translate. Both problems require relatively non-trivial handling and complicate one another.
The solution
I'll describe and provide sample code for non-optimal but working on most simple pages solution. In general, it is possible to achieve a perfect and more efficient solution, but, again, this goes beyond the scope of an answer. Obviously, it is IE8 only, so you'll need to check browser version and execute different handlers for IE8 vs. IE9 or higher, but you can take some ideas to improve other browsers rendering too.
There are two interrelated workarounds here.
Up-scaling
First, how do we upscale the vector content to the printer quality if we can't transform? The workaround here is to render to a context compatible with printer dc. What will happen is that content will be rendered at printer DPI. Note it will not fit exactly printer width, it will scale to printerDPI/screenDPI.
Later, on rasterization, we downscale to fit the printer width. We render initially to EMF, so there is no much of a quality loss (that will occur on the printer itself anyway). If you need higher quality (I doubt it), there are two possibilities - modify the solution to render for target width (this is not trivial) or work with resulting emf instead of bitmap and let printer to make the downscale fit.
Another note is that you currently use just printer width, but there may be non-printable margins that you need to query from printer and account for them. So it may re-scaled by printer even if you provide bitmap in exact printer dimensions. But again, I doubt this resolution disparity will make any difference for your project.
Clipping
Second to overcome is the clipping. To overcome this limitation, we render content in small chunks so they are not clipped by the renderer. After rendering a chunk, we change the scroll position of the document and render next chunk to the appropriate position in the target DC. This can be optimized to use larger chunks e.g. nearest DPI multiple to 1024 (using window resize), but I didn't implement that (it is just a speed optimization). If you don't make this optimization, ensure that minimum browser window size is not too small.
Note, doing this scroll on an arbitrary fractional scale will be an approximation and is not so simple to implement in generic case. But with regular printer and screen we can make integer chunk steps in multiplies of DPI, e.g. if screen is 96 DPI and printer is 600DPI, we make steps in the same multiple of 96 and 600 on each context and everything is much simpler. However, the remainder from top or bottom after processing all whole chunks will not be in DPI multiplies so we can't scroll as easily there.
In general, we can approximate scroll position in printer space and hope there will be no misfit between final chunks. What I did instead is appending an absolutely positioned div with chunk size at the right bottom of the page.
Note, this can interfere with some pages and change the layout (probably not the case with simple reports). If that is a problem, you'll need to add remainder handling after loops instead of adding an element. Most simple solution in that case is still to pad with div but not with the full chunk size but just to make content width multiple of screen DPI.
Even simpler idea, as I've realized later, is just to resize window to the nearest multiple of DPI and take this window size as a chunk size. You can try that instead of div, this will simplify the code and fix pages that may interfere with the injected div.
The code
This is just a sample.
No error handling. You need to add checks for every COM and API call, etc.
No code style, just quick and dirty.
Not sure all acquired resources are released as needed, do your checks
You must disable page borders on browser control for this sample to work (if you need borders around browser, just render them separately, built-in are not consistent anyway). On IE8 this is not so trivial but there are many answers here or on the web. Anyway, I will include this patch in sample solution project. You can render with borders as well and exclude them, but this will be unnecessary complication for a problem that has simple solution.
The full solution project can be found at this link, I'll post only the relevant code here.
The code below renders the page and saves in c:\temp\test.emf + c:\temp\test.bmp
void convertEmfToBitmap(const RECT& fitRect, HDC hTargetDC, HENHMETAFILE hMetafile, LPCTSTR fileName);
CComPtr<IHTMLDOMNode> appendPadElement(IHTMLDocument2* pDoc, IHTMLElement* pBody, long left, long top, long width, long height);
void removeElement(IHTMLElement* pParent, IHTMLDOMNode* pChild);
void CMFCApplication1Dlg::OnBnClickedButton2()
{
COleVariant varNull;
COleVariant varUrl = L"http://www.google.com/search?q=ie+8+must+die";
m_browser.Navigate2(varUrl, varNull, varNull, varNull, varNull);
}
void CMFCApplication1Dlg::OnBnClickedButton1()
{
//get html interfaces
IDispatch* pHtmlDoc = m_browser.get_Document();
CComPtr<IHTMLDocument2> pHtmlDocument2;
pHtmlDoc->QueryInterface(IID_IHTMLDocument2, (void**)&pHtmlDocument2);
CComPtr<IHTMLElement> pBody;
pHtmlDocument2->get_body(&pBody);
CComPtr<IHTMLElement2> pBody2;
pBody->QueryInterface(IID_IHTMLElement2, (void**)&pBody2);
CComPtr<IHTMLBodyElement> pBodyElement;
pBody->QueryInterface(IID_IHTMLBodyElement, (void**)&pBodyElement);
CComPtr<IHTMLElement> pHtml;
pBody->get_parentElement(&pHtml);
CComPtr<IHTMLElement2> pHtml2;
pHtml->QueryInterface(IID_IHTMLElement2, (void**)&pHtml2);
CComPtr<IHTMLStyle> pHtmlStyle;
pHtml->get_style(&pHtmlStyle);
CComPtr<IHTMLStyle> pBodyStyle;
pBody->get_style(&pBodyStyle);
//get screen info
HDC hWndDc = ::GetDC(m_hWnd);
const int wndLogPx = GetDeviceCaps(hWndDc, LOGPIXELSX);
const int wndLogPy = GetDeviceCaps(hWndDc, LOGPIXELSY);
//keep current values
SIZE keptBrowserSize = { m_browser.get_Width(), m_browser.get_Height() };
SIZE keptScrollPos;
//set reasonable viewport size
//m_browser.put_Width(docSize.cx);
//m_browser.put_Height(docSize.cy*2);
pHtml2->get_scrollLeft(&keptScrollPos.cx);
pHtml2->get_scrollTop(&keptScrollPos.cy);
COleVariant keptOverflow;
pBodyStyle->get_overflow(&keptOverflow.bstrVal);
//setup style and hide scroll bars
pHtmlStyle->put_border(L"0px;");
pHtmlStyle->put_overflow(L"hidden");
pBodyStyle->put_border(L"0px;");
pBodyStyle->put_overflow(L"hidden");
//get document size and visible area in screen pixels
SIZE docSize;
pBody2->get_scrollWidth(&docSize.cx);
pBody2->get_scrollHeight(&docSize.cy);
RECT clientRect = { 0 };
pHtml2->get_clientWidth(&clientRect.right);
pHtml2->get_clientHeight(&clientRect.bottom);
//derive chunk size
const SIZE clientChunkSize = {
clientRect.right - clientRect.right % wndLogPx,
clientRect.bottom - clientRect.bottom % wndLogPy };
//pad with absolutely positioned element to have enough scroll area for all chunks
//alternatively, browser can be resized to chunk multiplies (simplest), to DPI multiplies (more work).
//This pad also can be made smaller, to modulus DPI, but then need more work in the loops below
CComPtr<IHTMLDOMNode> pPadNode =
appendPadElement(pHtmlDocument2, pBody, docSize.cx, docSize.cy, clientChunkSize.cx, clientChunkSize.cy);
//get printer info
CPrintDialog pd(TRUE, PD_ALLPAGES | PD_USEDEVMODECOPIES | PD_NOPAGENUMS | PD_HIDEPRINTTOFILE | PD_NOSELECTION);
pd.m_pd.Flags |= PD_RETURNDC | PD_RETURNDEFAULT;
pd.DoModal();
HDC hPrintDC = pd.CreatePrinterDC();
const int printLogPx = GetDeviceCaps(hPrintDC, LOGPIXELSX);
const int printLogPy = GetDeviceCaps(hPrintDC, LOGPIXELSY);
const int printHorRes = ::GetDeviceCaps(hPrintDC, HORZRES);
const SIZE printChunkSize = { printLogPx * clientChunkSize.cx / wndLogPx, printLogPy * clientChunkSize.cy / wndLogPy };
//browser total unscaled print area in printer pixel space
const RECT printRectPx = { 0, 0, docSize.cx* printLogPx / wndLogPx, docSize.cy*printLogPy / wndLogPy };
//unscaled target EMF size in 0.01 mm with printer resolution
const RECT outRect001Mm = { 0, 0, 2540 * docSize.cx / wndLogPx, 2540 * docSize.cy / wndLogPy };
HDC hMetaDC = CreateEnhMetaFile(hPrintDC, L"c:\\temp\\test.emf", &outRect001Mm, NULL);
::FillRect(hMetaDC, &printRectPx, (HBRUSH)::GetStockObject(BLACK_BRUSH));
//unscaled chunk EMF size in pixels with printer resolution
const RECT chunkRectPx = { 0, 0, printChunkSize.cx, printChunkSize.cy };
//unscaled chunk EMF size in 0.01 mm with printer resolution
const RECT chunkRect001Mm = { 0, 0, 2540 * clientChunkSize.cx / wndLogPx, 2540 * clientChunkSize.cy / wndLogPy };
////////
//render page content to metafile by small chunks
//get renderer interface
CComPtr<IHTMLElementRender> pRender;
pHtml->QueryInterface(IID_IHTMLElementRender, (void**)&pRender);
COleVariant printName = L"EMF";
pRender->SetDocumentPrinter(printName.bstrVal, hMetaDC);
//current positions and target area
RECT chunkDestRectPx = { 0, 0, printChunkSize.cx, printChunkSize.cy };
POINT clientPos = { 0, 0 };
POINT printPos = { 0, 0 };
//loop over chunks left to right top to bottom until scroll area is completely covered
const SIZE lastScroll = { docSize.cx, docSize.cy};
while (clientPos.y < lastScroll.cy)
{
while (clientPos.x < lastScroll.cx)
{
//update horizontal scroll position and set target area
pHtml2->put_scrollLeft(clientPos.x);
chunkDestRectPx.left = printPos.x;
chunkDestRectPx.right = printPos.x + printChunkSize.cx;
//render to new emf, can be optimized to avoid recreation
HDC hChunkDC = CreateEnhMetaFile(hPrintDC, NULL, &chunkRect001Mm, NULL);
::FillRect(hChunkDC, &chunkRectPx, (HBRUSH)::GetStockObject(WHITE_BRUSH));
pRender->DrawToDC(hChunkDC);
HENHMETAFILE hChunkMetafile = CloseEnhMetaFile(hChunkDC);
//copy chunk to the main metafile
PlayEnhMetaFile(hMetaDC, hChunkMetafile, &chunkDestRectPx);
DeleteEnhMetaFile(hChunkMetafile);
//update horizontal positions
clientPos.x += clientChunkSize.cx;
printPos.x += printChunkSize.cx;
}
//reset horizontal positions
clientPos.x = 0;
printPos.x = 0;
//update vertical positions
clientPos.y += clientChunkSize.cy;
printPos.y += printChunkSize.cy;
pHtml2->put_scrollTop(clientPos.y);
chunkDestRectPx.top = printPos.y;
chunkDestRectPx.bottom = printPos.y + printChunkSize.cy;
}
//restore changed values on browser
//if for large pages on slow PC you get content scrolling during rendering and it is a problem,
//you can either hide the browser and show "working" or place on top first chunk content
pBodyStyle->put_overflow(keptOverflow.bstrVal);
pHtml2->put_scrollLeft(keptScrollPos.cx);
pHtml2->put_scrollTop(keptScrollPos.cy);
m_browser.put_Width(keptBrowserSize.cx);
m_browser.put_Height(keptBrowserSize.cy);
removeElement(pBody, pPadNode);
//draw to bitmap and close metafile
HENHMETAFILE hMetafile = CloseEnhMetaFile(hMetaDC);
RECT fitRect = { 0, 0, printHorRes, docSize.cy * printHorRes / docSize.cx };
convertEmfToBitmap(fitRect, hWndDc, hMetafile, L"c:\\temp\\test.bmp");
DeleteEnhMetaFile(hMetafile);
//cleanup - probably more here
::ReleaseDC(m_hWnd, hWndDc);
::DeleteDC(hPrintDC);
//{
// std::stringstream ss;
// ss << "====" << docSize.cx << "x" << docSize.cy << " -> " << fitRect.right << "x" << fitRect.bottom << "" << "\n";
// OutputDebugStringA(ss.str().c_str());
//}
}
///////////////
////some util
void convertEmfToBitmap(const RECT& fitRect, HDC hTargetDC, HENHMETAFILE hMetafile, LPCTSTR fileName)
{
//Create memory DC to render into
HDC hCompDc = ::CreateCompatibleDC(hTargetDC);
//NOTE this
BITMAPINFOHEADER infoHeader = { 0 };
infoHeader.biSize = sizeof(infoHeader);
infoHeader.biWidth = fitRect.right;
infoHeader.biHeight = -fitRect.bottom;
infoHeader.biPlanes = 1;
infoHeader.biBitCount = 24;
infoHeader.biCompression = BI_RGB;
BITMAPINFO info;
info.bmiHeader = infoHeader;
//create bitmap
BYTE* pMemory = 0;
HBITMAP hBitmap = ::CreateDIBSection(hCompDc, &info, DIB_RGB_COLORS, (void**)&pMemory, 0, 0);
HBITMAP hOldBmp = (HBITMAP)::SelectObject(hCompDc, hBitmap);
PlayEnhMetaFile(hCompDc, hMetafile, &fitRect);
BITMAPFILEHEADER fileHeader = { 0 };
fileHeader.bfType = 0x4d42;
fileHeader.bfSize = 0;
fileHeader.bfReserved1 = 0;
fileHeader.bfReserved2 = 0;
fileHeader.bfOffBits = sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
CFile file(
fileName,
CFile::modeCreate | CFile::modeReadWrite | CFile::shareDenyNone);
file.Write((char*)&fileHeader, sizeof(fileHeader));
file.Write((char*)&infoHeader, sizeof(infoHeader));
int bytes = (((24 * infoHeader.biWidth + 31) & (~31)) / 8) * abs(infoHeader.biHeight);
file.Write(pMemory, bytes);
::SelectObject(hCompDc, hOldBmp);
//Clean up
if (hBitmap)
::DeleteObject(hBitmap);
::DeleteDC(hCompDc);
}
CComPtr<IHTMLDOMNode> appendPadElement(IHTMLDocument2* pDoc, IHTMLElement* pBody, long left, long top, long width, long height)
{
CComPtr<IHTMLElement> pPadElement;
pDoc->createElement(L"DIV", &pPadElement);
CComPtr<IHTMLStyle> pPadStyle;
pPadElement->get_style(&pPadStyle);
CComPtr<IHTMLStyle2> pPadStyle2;
pPadStyle->QueryInterface(IID_IHTMLStyle2, (void**)&pPadStyle2);
pPadStyle2->put_position(L"absolute");
CComVariant value = width;
pPadStyle->put_width(value);
value = height;
pPadStyle->put_height(value);
pPadStyle->put_posLeft((float)left);
pPadStyle->put_posTop((float)top);
CComPtr<IHTMLDOMNode> pPadNode;
pPadElement->QueryInterface(IID_IHTMLDOMNode, (void**)&pPadNode);
CComPtr<IHTMLDOMNode> pBodyNode;
pBody->QueryInterface(IID_IHTMLDOMNode, (void **)&pBodyNode);
pBodyNode->appendChild(pPadNode, NULL);
return pPadNode;
}
void removeElement(IHTMLElement* pParent, IHTMLDOMNode* pChild)
{
CComPtr<IHTMLDOMNode> pNode;
pParent->QueryInterface(IID_IHTMLDOMNode, (void **)&pNode);
pNode->removeChild(pChild, NULL);
}
Sample page output (4958x7656)
I have taken your code and run it on IE11 when the WebBrowser control is smaller then the page size. It rendered a portion of the page equal to control's size. Not sure why you say IE8 and IE11 are any different.
It seems that common approach to taking full page screenshots is adjusting WebBrowser size before taking screenshot, like this:
const long oldH = m_browser.get_Height();
const long oldW = m_browser.get_Width();
m_browser.put_Height(n_scrollHeight);
m_browser.put_Width(n_scrollWidth);
//Do the upscaling & render -- note that IE8 fails to render it here!!!!
pViewObject->Draw(DVASPECT_CONTENT, //DVASPECT_DOCPRINT
-1, NULL, NULL, NULL, hCompDc,
&rectPrnt,
NULL,
NULL, 0);
m_browser.put_Height(oldH);
m_browser.put_Width(oldW);
This seems to work well, even on large pages such as the one you're currently reading (I have taken screenshot 1920x8477). It works both on my IE11 and on IE8 virtual machine
It has a side effect of resetting scrollbars, but that can be solved, for example by using an invisible copy of WebBrowser for screenshots.
PS: You could have done a better job by providing example code that can be compiled, at least ;)
I have a check box that I want to accurately measure so I can position controls on a dialog correctly. I can easily measure the size of the text on the control - but I don't know the "official" way of calculating the size of the check box and the gap before (or after) the text.
I'm pretty sure the width of the checkbox is equal to
int x = GetSystemMetrics( SM_CXMENUCHECK );
int y = GetSystemMetrics( SM_CYMENUCHECK );
You can then work out the area inside by subtracting the following ...
int xInner = GetSystemMetrics( SM_CXEDGE );
int yInner = GetSystemMetrics( SM_CYEDGE );
I use that in my code and haven't had a problem thus far ...
Short answer:
Long Version
From MSDN Layout Specifications: Win32, we have the specifications of the dimensions of a checkbox.
It is 12 dialog units from the left edge of the control to the start of the text:
And a checkbox control is 10 dialog units tall:
Surfaces and Controls Height (DLUs) Width (DLUs)
===================== ============= ===========
Check box 10 As wide as possible (usually to the margins) to accommodate localization requirements.
First we calculate the size of a horizontal and a vertical dialog unit:
const dluCheckBoxInternalSpacing = 12; //12 horizontal dlus
const dluCheckboxHeight = 10; //10 vertical dlus
Size dialogUnits = GetAveCharSize(dc);
Integer checkboxSpacing = MulDiv(dluCheckboxSpacing, dialogUnits.Width, 4);
Integer checkboxHeight = MulDiv(dluCheckboxHeight, dialogUnits.Height, 8);
Using the handy helper function:
Size GetAveCharSize(HDC dc)
{
/*
How To Calculate Dialog Base Units with Non-System-Based Font
http://support.microsoft.com/kb/125681
*/
TEXTMETRIC tm;
GetTextMetrics(dc, ref tm);
String buffer = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
Size result;
GetTextExtentPoint32(dc, buffer, 52, out result);
result.Width = (result.X/26 + 1) / 2; //div uses trunc rounding; we want arithmetic rounding
result.Height = tm.tmHeight;
return result;
}
Now that we know how many pixels (checkboxSpacing) to add, we calculate the label size as normal:
textRect = Rect(0,0,0,0);
DrawText(dc, Caption, -1, textRect, DT_CALCRECT or DT_LEFT or DT_SINGLELINE);
chkVerification.Width = checkboxSpacing+textRect.Right;
chkVerification.Height = checkboxHeight;
Bonus Reading
What's a dialog unit?
A dialog is a unit of measure based on the user's preferred font size. A dialog unit is defined such that the average character is 4 dialog units wide by 8 dialog units high:
This means that dialog units:
change with selected font
changed with selected DPI setting
are not square
Note: Any code released into public domain. No attribution required.
Sorry for resurrecting this old thread. I recently found myself wondering about the exact same question. Currently, none of the answers above give a result consistent with Windows 10 for different fonts and font sizes, especially in high-DPI environments.
Instead, it seems that the correct result is obtained by
SIZE szCheckBox;
GetThemePartSize(hTheme, hDC, BP_CHECKBOX, CBS_UNCHECKEDNORMAL, &rcBackgroundContent, TS_TRUE, &szCheckBox);
for the size of the checkbox itself. And
SIZE szZeroCharacter;
GetTextExtentPoint32(hDC, L"0", 1, &szZeroCharacter);
int iGapWidth = szZeroCharacter.cx / 2;
for the width of the gap. After trying a lot of different methods inspired by the posts above, I found L"0" in the dissembly of comctl32.dll. And while it looks like a joke to me (not necessarily a good one), I suspect it's a holdover from the old days when this might have been a good enough approximation of 2DLU.
Disclaimer: While I tested the result with various fonts and different sizes on Windows 10, I have not attempted to verify that it also holds on any other (older) version of the operating system.
It is a shame that Microsoft did not provide a way to know this for sure. I was struggling with the same question and the answer provided above is not complete. The main problem with it is that if the font of the dialog window is set to something other than the default size, that solution will not work because checkboxes will be resized.
Here's how I solved this issue (it is just an approximation that seems to have worked for me). The code is for MFC project.
1 - Create two test controls on your form, a checkbox and a radio box:
2 - Define the following custom struct:
struct CHECKBOX_DIMS{
int nWidthPx;
int nHeightPx;
int nSpacePx; //Space between checkbox and text
CHECKBOX_DIMS()
{
nWidthPx = 0;
nHeightPx = 0;
nSpacePx = 0;
}
};
3 - Call the following code when form initializes for each of the test controls (that will measure them and remove them so that end-users don't seem them):
BOOL OnInitDialog()
{
CDialog::OnInitDialog();
//Calculate the size of a checkbox & radio box
VERIFY(GetInitialCheckBoxSize(IDC_CHECK_TEST, &dimsCheckBox, TRUE));
VERIFY(GetInitialCheckBoxSize(IDC_RADIO_TEST, &dimsRadioBox, TRUE));
//Continue with form initialization ...
}
BOOL GetInitialCheckBoxSize(UINT nCtrlID, CHECKBOX_DIMS* pOutCD, BOOL bRemoveCtrl)
{
//Must be called initially to calculate the size of a checkbox/radiobox
//'nCtrlID' = control ID to measure
//'pOutCD' = if not NULL, receives the dimensitions
//'bRemoveCtrl' = TRUE to delete control
//RETURN:
// = TRUE if success
BOOL bRes = FALSE;
//Get size of a check (not exactly what we need)
int nCheckW = GetSystemMetrics(SM_CXMENUCHECK);
int nCheckH = GetSystemMetrics(SM_CYMENUCHECK);
//3D border spacer (not exactly what we need either)
int nSpacerW = GetSystemMetrics(SM_CXEDGE);
//Get test checkbox
CButton* pChkWnd = (CButton*)GetDlgItem(nCtrlID);
ASSERT(pChkWnd);
if(pChkWnd)
{
CRect rcCheckBx;
pChkWnd->GetWindowRect(&rcCheckBx);
//We need only the height
//INFO: The reason why we can't use the width is because there's
// an arbitrary text followed by a spacer...
int h = rcCheckBx.Height();
CDC* pDc = pChkWnd->GetDC();
if(pDc)
{
//Get horizontal DPI setting
int dpiX = pDc->GetDeviceCaps(LOGPIXELSX);
//Calculate
if(pOutCD)
{
//Use height as-is
pOutCD->nHeightPx = h;
//Use height for the width
pOutCD->nWidthPx = (int)(h * ((double)nCheckW / nCheckH));
//Spacer is the hardest
//INFO: Assume twice and a half the size of 3D border &
// take into account DPI setting for the window
// (It will give some extra space, but it's better than less space.)
// (This number is purely experimental.)
// (96 is Windows DPI setting for 100% resolution setting.)
pOutCD->nSpacePx = (int)(nSpacerW * 2.5 * dpiX / 96.0);
}
//Release DC
pChkWnd->ReleaseDC(pDc);
if(bRemoveCtrl)
{
//Delete window
bRes = pChkWnd->DestroyWindow();
}
else
{
//Keep the window
bRes = TRUE;
}
}
}
return bRes;
}
4 - Now you can easily resize any checkbox or radio box by calling this:
//Set checkbox size & new text
VERIFY(SetCheckBoxTextAndSize(this, IDC_CHECK_ID, &dimsCheckBox, L"New text") > 0);
//Just resize radio box
VERIFY(SetCheckBoxTextAndSize(this, IDC_RADIO_ID, &dimsRadioBox, NULL) > 0);
int SetCheckBoxTextAndSize(CWnd* pParWnd, UINT nCheckBoxID, CHECKBOX_DIMS* pDims, LPCTSTR pNewText)
{
//Set size of the checkbox/radio to 'pNewText' and update its size according to its text
//'pParWnd' = parent dialog window
//'nCheckBoxID' = control ID to resize (checkbox or radio box)
//'pDims' = pointer to the struct with checkbox/radiobox dimensions
//'pNewText' = text to set, or NULL not to change the text
//RETURN:
// = New width of the control in pixels, or
// = 0 if error
int nRes = 0;
ASSERT(pParWnd);
ASSERT(pDims);
CButton* pChkWnd = (CButton*)pParWnd->GetDlgItem(nCheckBoxID);
ASSERT(pChkWnd);
if(pChkWnd)
{
CDC* pDc = pChkWnd->GetDC();
CFont* pFont = pChkWnd->GetFont();
if(pDc)
{
if(pFont)
{
//Make logfont
LOGFONT lf = {0};
if(pFont->GetLogFont(&lf))
{
//Make new font
CFont font;
if(font.CreateFontIndirect(&lf))
{
//Get font from control
CFont* pOldFont = pDc->SelectObject(&font);
//Get text to set
CString strCheck;
if(pNewText)
{
//Use new text
strCheck = pNewText;
}
else
{
//Keep old text
pChkWnd->GetWindowText(strCheck);
}
//Calculate size
RECT rc = {0, 0, 0, 0};
::DrawText(pDc->GetSafeHdc(), strCheck, strCheck.GetLength(), &rc, DT_CALCRECT | DT_NOPREFIX | DT_SINGLELINE);
//Get text width
int nTextWidth = abs(rc.right - rc.left);
//See if it's valid
if(nTextWidth > 0 ||
(nTextWidth == 0 && strCheck.GetLength() == 0))
{
//Get location of checkbox
CRect rcChk;
pChkWnd->GetWindowRect(&rcChk);
pParWnd->ScreenToClient(rcChk);
//Update its size
rcChk.right = rcChk.left + pDims->nWidthPx + pDims->nSpacePx + nTextWidth;
//Use this line if you want to change the height as well
//rcChk.bottom = rcChk.top + pDims->nHeightPx;
//Move the control
pChkWnd->MoveWindow(rcChk);
//Setting new text?
if(pNewText)
{
pChkWnd->SetWindowText(pNewText);
}
//Done
nRes = abs(rcChk.right - rcChk.left);
}
//Set font back
pDc->SelectObject(pOldFont);
}
}
}
//Release DC
pChkWnd->ReleaseDC(pDc);
}
}
return nRes;
}
I'd like to give my 2 cents on the matter since iv spent an entire day working on an accurate solution for this problem that takes DPI awareness and fonts into consideration.
First define the checkbox's size in units.
#define CHECKBOX_INTERNAL_SIZE 12
Then i defined a function for converting units to pixels. NOTE: MulDiv may work just as good.
double dpi_MulDiv(double nNumber, double nNumerator, double nDenominator)
{
return (nNumber * nNumerator) / nDenominator;
}
Finally the function that does the magic. SEE the code comments for details.
//
// Get the minimum size of the Checkbox.
// NOTE: The font of the control must be set before calling this function.
//
SIZE dpi_GetCheckBoxWidth(HWND hWnd, int monitorDpi)
{
HDC dc;
HFONT hFont;
HFONT oldFont;
TEXTMETRIC tm;
double checkboxSize;
double whiteSpace;
WCHAR sourceString[128];
RECT txtRect;
SIZE size;
dc = GetDC(hWnd);
// Note that GetDC returns an uninitialized DC, which has "System" (a bitmap font) as the default font; thus the need to select a font into the DC.
hFont = (HFONT)SendMessage(hWnd, WM_GETFONT, 0, 0);
oldFont = (HFONT)SelectObject(dc, hFont);
// Get the Checkbox width.
checkboxSize = round(dpi_MulDiv(CHECKBOX_INTERNAL_SIZE, monitorDpi, 96));
// Get the space between the Checkbox and text.
GetTextMetrics(dc, &tm);
whiteSpace = round((double)tm.tmAveCharWidth / 2.0f);
// Get the Text width.
txtRect = { 0, 0, 0, 0 };
if (GetWindowTextW(hWnd, sourceString, 128) != 0)
{
DrawTextW(dc, sourceString, -1, &txtRect, DT_CALCRECT | DT_LEFT | DT_SINGLELINE);
}
// Cleanup.
SelectObject(dc, oldFont);
ReleaseDC(hWnd, dc);
// Done.
size.cx = (LONG)checkboxSize + (LONG)whiteSpace + txtRect.right + 3;
size.cy = ((LONG)checkboxSize < txtRect.bottom) ? txtRect.bottom : (LONG)checkboxSize;
return size;
}
I added + 3 on the last line that computes the width as a way to adjust for little irregularities. Feed back on this is welcomed. Iv only tested on Windows 10 thus far with different fonts and sizes.
This code doesn't work on Win7 with scaled UI (fonts 125% larger or 150% larger). The only thing that seems to work is:
int WID = 13 * dc.GetDeviceCaps(LOGPIXELSX) / 96;
int HEI = 13 * dc.GetDeviceCaps(LOGPIXELSY) / 96;
Ok dudes my way is maybe not the fastes to use in runtime, but it works for me in any case i have tested so far.
In the beginnin of my proggys i put in a function to get the size and store it in a global variable (yeah i have heard this would be bad, but i dont care about this)
here the explanation:
Create a treeview (invisible if u want)
Create an imagelist with atleast 1 image inside (size 16x16)
Set the imagelist to the treeview ("TVSIL_NORMAL")
Get the "TVSIL_STATE" imagelist from the treeview (u have to create "TVSIL_NORMAL" before, otherwise this one will fail!)
Use ImageList_GetIconSize(..) and store the size. Wow, the checkboxs and the radio-buttons have the same size as the state icons of the treeview. Now u have what u want!
Destroy the "TVSIL_NORMAL" imagelist
Destroy the treeview
this code needs only a few microseconds at the beginning of my proggies and i can use the value everytime i need it.
Preamble:
I had the same question while trying to determine the needed size of the checkbox control for a given text and found that the existing answers didn't really work for me, for several reasons:
SM_CXMENUCHECK doesn't account for the gap. In fact, I'm not convinced this is even for regular checkboxes, although it may have the same value. It may also be dependent on visual styles being enabled.
The other answers were overly complicated and felt a bit hacky (no disrespect intended, it is MS that don't make this easy).
The stated 12DLU layout was very helpful, although again feels arbitrary without a system metric to rely on.
The answers I tried still didn't yield a high enough pixel value to stop the checkbox text from wrapping.
My investigation:
I looked at how Wine reproduces the behavior and found that it also gives the same results as simply assuming 12DLU. However, the text still wrapped unless I added an extra 3 pixels to the width (even though the text should fit fine without). I also noticed that GetTextExtentPoint32 yields a value of 3 for an empty string (hmmm...)
Turning off the BS_MULTILINE style obviously stopped the text wrapping. My guess is that DrawTextW's word wrapping calculations are imperfect.
At this point I decided that the simplest solution was to just add 1 extra space to GetTextExtentPoint32, so that there would definitely be enough pixels. The over-estimate of a couple of pixels was acceptable to me.
Note that this all assumes your application is manifested as DPI aware. Otherwise I found the checkbox appeared much larger on some Windows 7 systems (not all though).
My (mostly Wine's) solution:
// This code gets the size of a piece of text and adds the size of a
// checkbox and gap. Note that this is very rough code with no error handling.
BOOL isCheckbox = TRUE;
HWND dialog = ... // Your control or dialog
HFONT font = ... // The font your control will use if it hasn't been set yet
PTCHAR text = ... // Your text
HFONT currentFont;
SIZE size;
HDC dc = GetDC(dialog);
if (!font) {
font = (HFONT)SendMessage(dialog, WM_GETFONT, 0, 0);
}
currentFont = (HFONT)SelectObject(dc, font); // NB: You should add error handling here
if (isCheckbox) {
// Or you can disable BS_MULTILINE
_tcscat(text, TEXT(" ")); // NB: This assumes text is allocated for +1 char
}
GetTextExtentPoint32(dc, text, _tcslen(text), &size); // NB: You should add error handling here
if (isCheckbox) {
int checkBoxWidth = 12 * GetDeviceCaps(dc, LOGPIXELSX ) / 96 + 1;
int checkBoxHeight = 12 * GetDeviceCaps(dc, LOGPIXELSY ) / 96 + 1;
int textOffset;
GetCharWidthW(dc, '0', '0', &textOffset);
textOffset /= 2;
size->cx += checkBoxWidth + textOffset;
if (size->cy < checkBoxHeight) {
size->cy = checkBoxHeight;
}
}
if (currentFont) {
SelectObject(dc, currentFont);
}
ReleaseDC(dialog, dc);