Simulation of videosignal lost.

[Starterz]

Hi, friends! Here it is:

Code: Select all

  //! Simulation of videosignal lost. Call this fun. inside main loop.
  //! Returns true if videosignal from camera is 'lost'.
  //! NOTE: MUST NOT use if() before itself
  //! or after 'if(smth) emulCamDamage()' use: 
  //! '..else device->getSceneManager()->getRootSceneNode()->setVisible(true);'
  bool emulCamDamage(u8 damage //! Damage level [0..255] 0-is no damage.
                    ,ICameraSceneNode* camera
                    ,IrrlichtDevice* device
                    ,wchar_t* mess=L"V I D E O S I G N A L   I S   L O S T"
                    ,IGUIFont* font=0)
  {
    if(!device) return true;
    ISceneManager* smgr=device->getSceneManager();
    ISceneNode* rsn=smgr->getRootSceneNode();
    if(camera!=smgr->getActiveCamera())
    {
      rsn->setVisible(true);
      return true;
    }

    static s32 comatoz;
    if(--comatoz<0) comatoz=0;
    IVideoDriver* driver=device->getVideoDriver();
    if(!comatoz&&rand()%255<damage)
    {
      u32 coma=driver->getFPS();
      comatoz=1+rand()%++coma;	//! (0..1] in seconds.
    }
    smgr->getRootSceneNode()->setVisible(!comatoz);
    if(!comatoz) return false;

    rect<s32> view=driver->getViewPort();
    u32 x=view.getSize().Width;
    u32 y=view.getSize().Height;
    s32 sfc=x*y/100;		//! Let's get enough green snowflakes ;)
    for(s32 j=0; j<sfc; j++)
      driver->drawPixel(rand()%(x+1),rand()%(y+1)
                        ,SColor(255,0,255,0));
    if(mess) //! Tells that a signal from camera is lost.
    {
      IGUIEnvironment* env=device->getGUIEnvironment();
      if(!font) font=env->getSkin()->getFont();
      font->draw(mess
                 ,view
                 ,SColor(255,255,255,0)
                 ,true,true);
    }
    device->sleep(10);		//! Some rest when show just a noise.
    return true;
  }

Now we can have fun with "broadcast" from our 'robots'!

[Virion]

any screenshot?

[ArakisTheKitsune]

@Starterz: You forgot to call srand function.

[Starterz]

@Starterz: You forgot to call srand function.

I don't know what to say to you... Do you really think it should be called here?

What about screenshots. This code simulates electronic noise on the screen,
when videosignal is lost. You can try call my function into any Irr standart example (Hallo world etc..) And you'll see all by your self.

Do it like this:

...
emulCamDamage(30,cameraFPS,device);
driver->beginScene();
smgr->drawAll();
driver->endScene();
...

And you'll see all by your self.

[ArakisTheKitsune]

@Starterz: You forgot to call srand function.

I don't know what to say to you... Do you really think it should be called here?

IMHO yes. Because if you don't you will always get same random numbers.
Of course user can call srand outside your code but this way looks more elegant to me. But that is just my opinion.

[Anoyser]

Hi!
Is it possible to get this working over 2d objects too?
If yes, how?

Thanks in advance

[devsh]

very inefficient, do it in a shader

[freetimecoder]

What about screenshots. This code simulates electronic noise on the screen,
when videosignal is lost. You can try call my function into any Irr standart example (Hallo world etc..) And you'll see all by your self.

We are coders.
We are lazy.



greetings

[Anoyser]

very inefficient, do it in a shader

Was that directed to me or op, both maybe?
I'm pretty new to graphics programming (not programming in general), so i don't know how i can do it in a shader.
And i don't need efficiency since I'm just creating something fun for my GF.
It has a max of 15-20 2D animations at once.
I only need to "hide" the 2D animations while the noise is happening.
So, is that possible some way to do with this piece of code?

Thanks

[roelor]

I like how this code is made, but I think the result is very unsatisfying, just some random green pixels and a video signal lost text in the middle of the screen.

I think its something I can learn from though, thanks anyway.

[REDDemon]

in the GLSL i found that there is a noise function that can simulate that with a shader and it is faster. maybe you can be interested in it