I am using SDL_gfx trying to resize an image but i can't really get it done.
The case is that I have an :
SDL_Surface* screen = SDL_SetVideoMode(0,0,32,SDL_FULLSCREEN);
and I also have a:
SDL_Surface* back_img = SDL_Load("back.jpg");
As you can see, I set the videomode to full screen, so the size of the screen surface will vary from pc to pc. I want to find a way to make back_img FIT on screen but i have two major problems.
screen->w and screen->h return a false value!
I can't resize the image to the specific size I want.
Any help?
Your screen->w values return 0 because you set them to zero with SDL_SetVideoMode(0,0,...
Set them to some proper values like SDL_SetVideoMode(800,600,32,SDL_FULLSCREEN); you can change them later by calling the function again with different parametes.
Note; setting SDL fullscreen will automatically resize and stretch the image to fit the screen
you can use SDL_VideoInfo to get the current resolution. See the code below:
const SDL_VideoInfo *info = SDL_GetVideoInfo();
SDL_Surface *screen = SDL_SetVideoMode( info->current_w, info->current_h, 32, SDL_FULLSCREEN );
Now your screen's resolution will match every PC's resolution.
Related
This may be a simple question but I'm having a hard time finding a straight answer to it: is there a way to resize a loaded Texture in SFML 2.0? For instance, if I have a 3264x2448 png and I want to scale it down to fit a 900x1200 rendered window without cropping, how would I do so?
Is there a way to scale all rendered windows to fit whatever monitor
of whatever system the application is running on?
First, here's a way to scale the image to the current RenderWindow size.
// assuming the given dimension
// change this dynamically with the myRenderWindow->getView().getSize()
sf::Vector2f targetSize(900.0f, 1200.0f);
yourSprite.setScale(
targetSize.x / yourSprite.getLocalBounds().width,
targetSize.y / yourSprite.getLocalBounds().height);
Be aware that this may stretch your image if the aspect ratio is not maintained. You might want to add code to adjust the decision for your case.
Then, if you want to stretch the RenderWindow to fill all the screen, may I suggest you use fullscreen mode?
Here's a snippet of how it's done:
// add the flag to the other ones
mStyleFlag = sf::Style::Default | sf::Style::Fullscreen;
// get the video mode (which tells you the size and BPP information of the current display
std::vector<sf::VideoMode> VModes = sf::VideoMode::getFullscreenModes();
// then create (or automatically recreate) the RenderWindow
mMainWindow.create(VModes.at(0), "My window title", mStyleFlag);
is there a way to resize a loaded Texture in SFML 2.0?
Not an sf::Texture directly. But you can use an sf::Sprite: you load load your texture, you pass it to an sf::Sprite and you play with sf::Sprite::setScale or sf::Sprite::scale.
I have a splash screen image that I display with splash.showFullScreen() but it doesn't re size it to the screen resolution so it either comes out tiled or to large depending on the display. I have tried everything I can think of but nothing works. This might sound like a stupid question which it probably is but I can't find the answer so if any can just help me with this? If it makes a difference I use a QPixmap named pixmap for the splash image. By the way I want the image to be stretched to the screen resolution.
You should scale the pixmap to the size of the screen with QPixmap::scaled(). You can get the screen resolution by calling QDesktopWidget::screenGeometry(). The desktop widget can be obtained by QApplication::desktop().
You can try something like this:
QDesktopWidget* desktopWidget = qApp->desktop();
QRect screenGeometry = desktopWidget->screenGeometry();
int screenWidth = screenGeometry.width();
int screenHeight = screenGeometry.height();
QPixmap pixmapForSplash = yourPixmap.scaled(screenWidth, screenHeight);
QSplashScreen splashScreen(pixmapForSplash);
(I'm sorry, I can not check this, because I do not have a development environment on this computer... I hope it is correct.)
I think you should call resize() method for your splash screen by the size of the available desktop geometry that you can get using QDesktopWidget::availableGeometry method. The QApplication::desktop() function is used to get an instance of QDesktopWidget.
slpashScreen.resize(QApplication::desktop()->avaiableGeometry().size());
If you use a QLabel to display the image, make sure the label is in a layout that will cause it to fill the entire parent widget and set the label to scale its contents using setScaledContents(true).
I am just starting with MFC so please be tolerant ;).
I have wrote (it was mostly generated to be honest) a simple application which should do the Paint chores: drawing lines, rectangulars, ellipses, changing a color of object to be drawn etc.
I need to save what has been drawn on the screen into a bmp file. Any ideas how can I achieve this ?
I do not know if that's relevant but I am drawing objects on the screen without the use of any CBitmaps or things like that. Here is a part of code responsible for drawing :
CPaintDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
Anchor.x=point.x;
Anchor.y=point.y;
OldPoint.x=Anchor.x;
OldPoint.y=Anchor.y;
if(pDoc->shapeCount>=MAX_SHAPES) return;
pDoc->shapeCount++;
if(bFreehand)
{
pDoc->m_shape[pDoc->shapeCount-1] = new Shape;
pDoc->m_shape[pDoc->shapeCount-1]->shape = ePoint;
}
if(bLine)
{
pDoc->m_shape[pDoc->shapeCount-1] = new CLine;
pDoc->m_shape[pDoc->shapeCount-1]->shape = eLine;
}
if(bRectangle)
{
pDoc->m_shape[pDoc->shapeCount-1] = new CRectangle;
pDoc->m_shape[pDoc->shapeCount-1]->shape = eRectangle;
}
if(bEllipse)
{
pDoc->m_shape[pDoc->shapeCount-1] = new CEllipse;
pDoc->m_shape[pDoc->shapeCount-1]->shape=eEllipse;
}
pDoc->m_shape[pDoc->shapeCount-1]->x=point.x;
pDoc->m_shape[pDoc->shapeCount-1]->y=point.y;
pDoc->m_shape[pDoc->shapeCount-1]->x2=point.x;
pDoc->m_shape[pDoc->shapeCount-1]->y2=point.y;
pDoc->m_shape[pDoc->shapeCount-1]->Pen=CurrentPen;
pDoc->m_shape[pDoc->shapeCount-1]->Brush=CurrentBrush;
bButtonDown=true;
SetCapture();
I have found this way to do it but I don't know how to obtain screen width and height to fill it in the CreateBitmap parameter's list
CBitmap *bitmap;
bitmap.CreateBitmap(desktopW, desktopH, 1, 32, rgbData);
CImage image;
image.Attach(bitmap);
image.Save(_T("C:\\test.bmp"), Gdiplus::ImageFormatBMP);
The CreateBitmap call only requires the desktop width and height if the image you wish to save is actually the entire size of the screen. If that's indeed your intent, you can use CWnd::GetDesktopWindow() to get a CWnd object that you can query for its width and height:
http://msdn.microsoft.com/en-us/library/bkxb36k8(v=VS.80).aspx
That gets dodgy in general...if for no other reason than multi-monitor scenarios...so I'd recommend against it unless you really feel like writing a screen capture app.
What you probably want to do isn't to take a full screen shot, but just save the contents of your program's window. Typically you'd do this by breaking out the drawing logic of your program so that in the paint method you call a helper function that is written to take a CDC device context. Then you can either call that function on the window-based DC you get in the paint call or on a DC you create from the bitmap to do your save. Note that you can use a CBitmap in CDC::SelectObject:
http://msdn.microsoft.com/en-us/library/432f18e2(v=VS.71).aspx
(Though let me pitch you on not using MFC. Try Qt instead. Way better.)
I have a visual C++ application that uses a CView derived class to render its display, which is primarily 3d vector data and true type text. The mapping mode used is either MM_ANISOTROPIC or MM_LOMETRIC. I can't use MM_TEXT as I use the same code for printing and plotting of the data and also have to overcome non-square screen pixel issues.
The drawing code currently draws directly onto the screen using the CViews OnDraw method and the CDC object provided. I am trying to replace this with drawing to a bitmap and blitting the bitmap to screen, using a CreateCompatibleDC / CreateCompatibleBitmap combination, as described in the MS documentation and elsewhere.
The problem is that the DCs are not compatible for mapping modes other than MM_TEXT, such that my view is rendered upside down and at the wrong scale. Investigation shows the following;
void CMyView::OnDraw(CDC *pDC)
{
CDC MyDC = CreateCompatibleDC(pDC); // Create a new memory DC;
int a = pDC->GetMapMode(),b = MyDC.GetMapMode();
'
'
'
}
a = 2
b = 1
Calling a SetMapMode on MyDC causes the display to be drawn entirely in black. Do I have to rewrite my code to suit MM_TEXT for drawing to a bitmap, or is there another way to overcome this problem.
You probably need to also call SetWindowExt and SetViewportExt. I have definitely used MM_ISOTROPIC with bitmap DCs before and it worked OK (don't have the code to hand as it was since ported to GDI+)
When I print the CDC for a report control that I've created it appears tiny (less than 1 square inch on paper). How can I get the report to be printed to occupy the entire page ?
Or in other words, how can I make the entire report to appear in one printed page.
CPrintDialog printDialog(FALSE);
printDialog.DoModal();
CDC dcPrint;
if(dcPrint.Attach(printDialog.GetPrinterDC()))
{
int iHorzRes = dcPrint.GetDeviceCaps(HORZRES);
int iVertRes = dcPrint.GetDeviceCaps(VERTRES);
int iHorzResCDC = m_CDC.GetDeviceCaps(HORZRES);
int iVertResCDC = m_CDC.GetDeviceCaps(VERTRES);
dcPrint.m_bPrinting = TRUE;
dcPrint.BitBlt(0,0, iHorzRes, iVertRes, &m_CDC, iHorzResCDC, iVertResCDC, SRCCOPY);
CFont* pOldFont = dcPrint.SelectObject(&m_HeaderFont);
dcPrint.TextOut(0,0,"HelloWorld") ;
dcPrint.SelectObject(pOldFont);
CPrintInfo printInfo;
printInfo.m_rectDraw.SetRect(0,0, iHorzRes, iVertRes);
dcPrint.StartDoc("Report Print");
dcPrint.StartPage();
if(dcPrint.EndPage())
dcPrint.EndDoc();
else
dcPrint.AbortDoc();
}
dcPrint.DeleteDC();
m_CDC is the memory DC that I use to buffer and display the entire report on screen.
As others have said, this is because, in general, the display resolution of printers is a lot higher than displays. Displays are usually 96 to 120DPI: at 96DPI this means that an image of 96 pixels (dots) by 96 pixels occupies approximately 1 square inch on the display. However, if you just take that image and print it out on a 600DPI printer, the size of the image will be about 1/6" by 1/6" - much smaller. This is a bane of the publishing world - images that look fine on displays often look either tiny or terrible when printed.
You could, as has been suggested, use StretchBlt rather than BitBlt to scale up your image. Depending on the difference between your display and printer, this will either look a bit blocky, or utterly hideously blocky.
A much better option is to rewrite your code that does the drawing of the control so that you've got a method that takes a device context (and some co-ordinates) and draws into it. Your normal window painting code can pass the memory DC to this routine and then BitBlt the result to the window, and your painting code can call this method with the printer DC and some suitable co-ordinates.
When writing this routine you'll have to worry about scaling: for example, you'll need to create fonts for the given device context, and with a scaling-indepdendant size (that is, specify the font size in points, not pixels), rather than relying on a pre-created font.
I suppose that you're not scaling your report to the printer's resolution. Typical screen resolution is 72 DPI (sometimes 96 DPI). Printer resolution can be 300DPI, 600DPI or higher.
You should repaint the report to the printer DC with all coordinates and sizes scaled to the printer's resolution.
Your printer has a lot more dots per inch than your screen. You will need to scale things to fit the printed page a bit better.
Try using StretchBlt() instead of BitBlt().