I am developing User Interface software using X11 programming.(I am not used QT, Widget, GTk).In that i want to increase font size using font property function. How can i use XFontProp function? Is there any other method to increase font size using X windows? If is it possible give me a sample?
If you want to use the old-fashioned now-deprecated server-side font rendering method, you cannot change the font size, you need to load the correctly-sized fond. Use XLoadFont and/or XLoadQueryFont for this. Use the Font you get in your GC.
To see what the string parameter looks like, type xlsfonts on your computer, or use xfontsel GUI utility.
Note that any given X server may lack fonts you want to use. There are only few mandatory fonts including fixed and I forgot what else.
If you want to use the fashionable modern client-side font rendering (what most programss written today are using) you have to use one of the toolkits, or Xft2 or Cairo libraries.
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I am working on an embedded platform (STM32F407) with a TFT LCD as a display (480x800px) and would like to make my user interface somewhat customizable to the end user. I figured the best source of fonts would be windows compatible as their the most common.
My current implementation uses my own custom drawn font in a binary format and a descriptor table giving the character width and ascii value but having to draw my own font bit by bit is tedious.
I would like to read in a True Type Font file from an SD card and be able to use the different sized glyphs inside it but I have not seen a strait forward implementation on how to actually achieve this magic. Can somebody point me to a good c/c++ example of what I am looking for?
Even better as a way to iron out the kinks I would like to make a simple gcc command line program that will print out my input with a selected font using '#' as pixels. That way I can just worry about implementation and not any other random bugs that might pop up.
Can anybody help me out?
Perhaps you can use the Freetype library.
As duskwuff says: TTF is primarily a vector format, would need to write a renderer. Better off using an image file to define the font, or using a bitmap font format like FNT (Windows) or BDF (UNIX).
Here is my answer to my own question: AngelCode's BMFont & Useage. This makes choosing selective characters from the installed char set, mix in a font and exports an image with a map file to each character. Simple to use.
I'm working on a Qt project and I've noticed a persistent problem with some GUI forms. The form looks fine on KDE (bottom picture) and Windows , but when the app runs on anything GNOME3-based (like Unity or GNOME3 itself) some parts of the form are hidden from view. (Top picture, everything below the Sort Ascending radio button is cut off)
The problem seems to be with how Qt layouts handle large font sizes. If the user is using normal-sized system font (<= 10pt) everything works fine. If they are using larger fonts, the form is not large enough to accommodate everything. Other forms affected by this bug are merely crowded, but that isn't as serious as having vital controls out of bounds. The layout doesn't want to resize itself to take advantage of new space if I enlarge the dialog. Is there an easy way to make it do this or do I need to hard-code it? Originally the code prevented dialog resizing during runtime, but restoring that functionality didn't fix the bug. Even if the dialog can expand, the problem is the layout won't expand with it.
Up until now, I've made all affected forms oversized to compensate for this bug, but it looks strange to have the dialogs much bigger than they need to be on Windows and KDE systems where the font is the proper size. Is there a way to cause an affected dialog/layout to resize itself so everything fits properly at runtime? If so, how would the program detect it when parts of the GUI are out of bounds? I would prefer not to force a certain font size (some people may prefer large fonts due to vision problems).
Thanks in advance for help.
The fix for this is using a different approach when displaying forms. A more dynamic way as I'll describe. I've successfully used this approach on Windows with 96 and very high DPI modes (over 120).
1.
Query the OS and get the user's chosen font for a particular system item; say the font used for the window caption or system dialog boxes. Also you could allow the user to choose their font later if they desired. Use True Type fonts when doing this if possible.
2.
Using that font, construct a string object that you'll use for a label or edit control (I don't know what this is for QT, for Windows it is GetTextExtentPoint32) and pass it to a system function to determine the width and height of the string for your environment.
3.
Given the above value, place the control and dynamically resize the form with the padding all around the control as you like. For buttons you might always add a certain percentage of pixels above and below the button to taste.
4.
For graphical elements like Bitmaps and jpegs, again query the OS for the current DPI settings of the monitor and use larger, pre-made resources. Naturally, all text around theses elements will be dynamically placed on the fly.
Note that on Windows you'll need to mark your exe as high dpi aware using a manifest.
Is there any way I can read the content of the framebuffer in Qt or anyway in C? I read it is possible to write the content of /dev/fb0 to a file and then load it. But is it possible to avoid saving it to memory and simply copy to a new memory location to use in Qt?
Thanks!
The ordinary Qt distribution is not likely to have special support for reading a framebuffer on Linux. It layers on top of X11 and is trying to provide cross-platform capability (as things like /dev/fb0 won't have meaning on Windows, for instance). So you would use higher level abstractions, such as the QPixmap::grabWindow() that #BerkDemirkir points out...probably a lot of hops through layers before the framebuffer.
(Note: If you are writing an ordinary cross platform Qt app intended to run in a windowed environment, that's certainly the route you want to go for a simple screen capture task!!)
On the other hand, Qt/Embedded is designed for Linux and to work with the QWS instead of X11. The mindset is that there's no windowing system and your app owns the whole screen. It writes directly to the framebuffer through a QScreen object, which has a base() method that can actually give you a pointer to the underlying memory:
http://doc.qt.nokia.com/4.7-snapshot/qscreen.html#base
Those are probably the only "Qt" ways to do these kinds of things. If you want an API instead of going through to /dev/fb0 directly you might investigate something like EZFB. (I didn't dig deep enough to know if it's useful or not, just found it with a query something like "linux framebuffer API")
http://freshmeat.net/projects/ezfb/
You can look this example to take a screenshot from any window (even desktop). Example uses QScreen::grabWindow() function to take screenshot.
Hello I am new to c++ and am wondering where to go about looking to print directly to the screen? For example the HUD interface that appears on laptops when you change the volume. I'm not really looking for any fancy graphics, just, say, a variable or info from a file.
I've tried googling but havn't come up with anything yet. So...where should I begin looking?
Thanks!
Under windows there are a few ways to do it. You could use DirectDraw Overlays (If the system supports them). Or you could create a layered window (WS_EX_LAYERED) and make everything but the bit you want to display transparent.
Pure C++ has only one screen interface, in the library. That's text-oriented. To do graphics, you need another OS-specific interface. So, you'd be looking at the API documentation for your OS.
BTW, the overlay graphics when you change the volume on your laptop are really special, IIRC. They're generated by your laptop itself, using System Management Mode - not the OS itself, and certainly not a program.
I'm looking for some API for printing.
Basically what I want to achieve is to print set of pixels(monochromatic bitmap which I store in memory) onto the generic paper format (A4,A5..etc.).
What I think that would be minimum API is:
printer devices list
printer buffer where I could send my in-memory pixmap (ex. like winXP printer tasks folder)
some API which would translate SI dimensions onto printer resolution, or according to previous - in memory pixmap (ex. 450x250) onto paper in appropriate resolution.
What I was considering is postScript, but I've some old LPT drived laserjet which probably doesn't support *PS.
Currently I'm trying to find something interesting in Qt - QGraphicsView.
http://doc.trolltech.com/4.2/qgraphicsview.html
Well you got close, look at Printing in Qt. There is the QPrinter class that implements some of what you are looking for. It is implmenetent as a QPaintDevice. This means that any widget that can render itself on the screen can be printed. This also mean you don't need to render to a bitmap to print, you can use Qt widgets or drawing functions for printing
On a side note, check the version number of the Qt documentation, the last release of Qt is 4.5, 4.6 is in beta.
You might want to investigate wx python for printing. Learning the framework might be a bit of an overhead for you though! I've had success with that in the past, both on windows and linux.
I've also used reportlab to make PDFs which are pretty easy to print using the minimum of OS interaction.
I would use PIL to create a BMP file, and then just use the standard OS services to print that file. PIL will accept data in either raster or vector form.