Jump to content
  • Advertisement


  • Content Count

  • Joined

  • Last visited

Community Reputation

122 Neutral

About tadobie

  • Rank
  1. tadobie

    optimizing pixmap reading

    HI, I am writing an app which does pixel by pixel comparison. I chose to use Qt because it seems to have plenty of really usable functionality and more importantly documentation that I can understand. The is one line of code which on diagnosis is the casue of my problems (the rest of my code runs at an acceptable rate). I am taking a screen grap(this occurs quickly enough), then using "pixmap.save()" to load a "BMP formated Image into a buffer. ie; QPixmap pmap; QByteArray array; QBuffer buf( array ); if ( !pmap.save( &buf, "BMP" ) ) cout << "error newImage to buffer" << endl; Since this process involves convert to a QImage and then writing to the buffer it is creating a bottle neck. It takes around 300ms. Is there a faster way to acheive the same result? eg. read straight to the memory buffer from the pixmap without the conversion step.
  2. tadobie

    screen to memory buffer

    OK, thanks heaps for you advise. I'll look into it.
  3. tadobie

    screen to memory buffer

    OK, The functionality I have at this point could easily be rewritten to be openGl complient if it can do what I need it to do (it's all just array comparisons and manipulation). If I need to create a display object, surface etc that's no problem. Is it worth it or will it just add more overhead and give me a less readable data structure (as SDL did)? (BTW I'm using a Linux based system, open source all the way!)
  4. tadobie

    screen to memory buffer

    not for a specific openGL app but thought that openGL might offer a way of capturing the screen an presenting it in a format I can us. Been trying to find out how (tryed SDL, wierd compresssed/ interlaced format that it too confusing to traverse through. ".bmp" format is easy to traverse though. Can you tell me if a screen capture using openGL can be organised into a particular format ( in my case an array representing a '.bmp" file)?
  5. tadobie

    screen to memory buffer

    I have multiple desktops running Each is controlled by an external device via wifi regular screen captures are made screen capture 1 is compared with screen capture 2 the differences are dynamically built into an array this array is sent to the appropriate device and changes the screen accordingly The only real bottle neck is that I way I have been performing the screen capture requires a Pixmap to be converted to an array which I can read quickly The rest of the process is negligable. All I need is a fast way to access the screen data.
  6. tadobie

    screen to memory buffer

    need to do pixel by pixel comparison for a streaming algorithm I've write that does something like a VNC operation
  7. HI all, I'm wondering about doing a screen capture that is will returns an array that represents a ".bmp" to memory (doing bitwise comparison). Until now I have been using Qt to do this. The problem is the screen capture returns a Pixmap which is converted to a bitmap and then read into a memory buffer. This is just to slow for what I want. It takes around 300ms to perform (3 and a bit frames per second, I don't think so!). If there is a way to capture the screen in openGL without having to convert to ".bmp" data I may be able to acheive the kinds of speeds I am looking for. any clues?
  8. tadobie

    development environments

    My biggest issue with KDevelop is the issue of configuration. I find it difficult to work out how to link includes and Libraries from other directories. For example I cant seem to get the program to link up with SDL.h and other external libraries. I'm not suggesting that it can't be done' it's just hthat I can seem to find any help on how it's done. I've fumbled around and work out a few things by trial and error but it's a such a hassle. Maybe someone can help me or direct me toward some documentation that explains it clearly. Unfortunatelty I came into the work of programming only relatively recently, that is to say I wasn't brought up on DOS and I'm new to Linux so my command line skills are poor. I guess the problem is that KDevelop shields me from these unknown demons for the most part but when it comes to linking, makefiles etc I guess the assumption is that you know what you're doing (yes, I'm afraid of the big bad command line). My ignorance is my downful, what should I do? Who should I turn to?
  9. tadobie

    development environments

    Oh! I had heard eclipse was build to "eclipse" sun's java dev environment so I'd never bothered to look at it. It seems interesting. Thanks guys Any other interesting invironments out there i should know about? (not a huge fan of the vi style environments (to lazy to remember all the key generated commands, I know it's slack but click and drag works for me any time)
  10. tadobie

    development environments

    Can anyone recommend a good development environment along the lines of Visual C++ that is NOT KDevelop!? I'm curious, does anyone even use KDevelop and if so is it generally a nightmare to use or is it just me?
  11. tadobie


    I'm developing an app under Linux in the KDevelop environment using Xlib and I'm wondering how to disable the Konsole that appears under my app. Any clues?
  12. tadobie

    screen grab

    Come to think of it, if there's an existing app or a couple of apps I can use together I'll do it but I need it to be GNU and better than VNC. I tryed that (a couple of different variations) and it was way below par for my liking. I figure it's mainly an issue with being able to access the screen buffer quickly enough and using as few processes as possible. Any clues?
  13. tadobie

    screen grab

    it's for a program to do something along the lines of what VNC or RDP do only it requires bit conversion from 32 to 18 bits and I'm runnning it over wifi. Trying to take advantage of a fast wifi connection. haven't used dev/fbo, in fact don't know much about the whole thing. I'm a newbie to Linux, only touched it for the first time last week! Any advice on what to do or where to find out?
  14. tadobie

    screen grab

    Does anyone know a really fast way to grab a screenshot? I have attempted to use import but I don't want to save the image to a file straight up. The idea is to manipulated the image (compare/compress) THEN save. Does anyone know about accessing the frame buffer and manipulating (as well as compare and compress I need to know about manipulating bit depth). Someone told me that they thought there was something to do with SOCKETS that might help me out. Beyond that I'm stuck. My knowledge does not extend past xgrab and import commands. It seems I have a lot to learn on the subject. Can anyone enlighten me further.
  15. tadobie

    Screen Capture

    thanks heaps Matt. I'm on my way now!
  • Advertisement

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

We are the game development community.

Whether you are an indie, hobbyist, AAA developer, or just trying to learn, GameDev.net is the place for you to learn, share, and connect with the games industry. Learn more About Us or sign up!

Sign me up!