xorg

Is there any command (or API) to set X.Org/Linux color brightness? In other words, I need something as handy as the xgamma command but for changing RGB brightness real-time . Is this possibile? Use the XF86VidMode* family of functions. #include <X11/Xlib.h> #include <X11/extensions/xf86vmode.h> #include <math.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> int main() { Display *display; int screen; int major, minor; int i; XF86VidModeGamma orig; display = XOpenDisplay(NULL); if (!display) return -1; screen = DefaultScreen(display); if (!XF86VidModeQueryVersion(display, &major,

I'd like to display a popover right above where the user is typing, in any Linux app (GTK, Qt, Electron, etc.), running on X. I figured out creating the popover, now I'm trying to figure out how to get the coordinates of the input text cursor (what blinks while you type, not sure if it's called "caret"?) relative to the screen. I know I can get info on where the mouse with xdotool : xdotool getmouselocation I would need the same thing but for the text cursor, in the currently focused window. I have no idea how to achieve this. I would love if someone could point me in the right direction. So,

I am starting a QT5 application with a rather complex design based on Qt Widgets. It runs on Beagleboard with a touchscreen. I will have a rather weird local invention instead of the LCD display. It's a laser painting on acrylic plate. It has no driver yet. To actually update a screen I must create a screenshot of the window as bitmap, turn it to grayscale and feed to a proprietary library, which will handle the laser. It should look cute, when ready. Unfortunately, the laser blinks on update, so I cannot just make screenshots on timer, or it will be jerky like hell. I need to run a function

since 4 days, I try to see how XLib works, and I have finally understood that. Si I tried to make a short program wich retrieve open window's name. For that, I created 2 functions : Window *list (Display *disp, unsigned long *len) { Atom prop = XInternAtom(disp,"_NET_CLIENT_LIST",False), type; int form; unsigned long remain; unsigned char *list; if (XGetWindowProperty(disp,XDefaultRootWindow(disp),prop,0,1024,False,XA_WINDOW, &type,&form,len,&remain,&list) != Success) { return 0; } return (Window*)list; } So, this first function return a window object of all the windows. Then, I created a

My data comes from an arduino (which gets it from a sensor). I'd like to have the data processed by an user program (after reading it from /dev/ttyUSB0 ). After that I need to control the mouse cursor using the output of the program. (I'd really like to avoid writing a kernel driver at this moment.) What is the recommended way to do this(on a Linux environment)? Perhaps a library on top of X...or some tool/script I can directly pipe the data into? Taken from dzone : #include <stdio.h> #include <stdlib.h> #include <X11/Xlib.h> #include <X11/Xutil.h> void mouseMove(int x, int y) { Display

The target language is C/C++ and the program has only to work on Linux, but platform independent solutions are preferred obviously. I run Xorg, XVideo and OpenGL are available. How many FPS can I expect on 1024x768 on an Intel Core 2 Duo with Intel graphics? (ONLY drawing counts, consider the arrays to be ready in RAM; no precise prognosis needed) The fastest way to draw a 2D array of color triplets: Use float ( not byte, not double) storage. Each triplet consists of 3 floats from 0.0 to 1.0 each. This is the format implemented most optimally by GPUs (but use greyscale GL_LUMINANCE storage

I'm trying to capture images with XGetImage. Everything fine but I need to send the data to a module which expects an array of RGB quads. Calling XGetPixel for every pixel in the image is very slow (0.5 seconds on a i5 for 1440x900 resolution). I've looked up the XGetPixel source code in xlib and the reason is obvious, a lot of computations are done for each pixel. Is there any efficient (or maybe completely different) way of doing this? With the MIT Shared Memory Extension you can store an image in a shared memory area. This way you avoid going through the Xlib IPC channel when processing the