Transparent background does not work on iPhone

[thichxemphim_01]

Hi everybody,

Currently, I am making a simple Irrlicht application on iPhone. My application has two windows. The first window display some objects using Irrlicht library and the second window displays an image. Since I would like to see the second windows as the background of objects (on the first windows) then I have implemented as followings:

- Place the first window in front of the second window so that we always see the first window.

- Set "backgroundColor" of first "window" and "glView" to "clearColor".

- Set the background of Irrlicht to transparent by using code:
driver->beginScene(true, true, SColor(0,0,0,0));

But when running application, I can not see the background on the second windows.
If I use OpenGL ES to draw objects directly on the first windows instead of using IrrLicht rendering, I can easily see the image on the second window.

does anybody have experience on this problem?
Any comment would be appreciated.

Thanks in advance.

PS: very sorry for my bad english

[Arcoroc]

Can you post some code?

[hybrid]

Ok, in order to collect all the previous replies in one clear comment:
Transparent backgrounds are pretty OS-specific things. I'm pretty sure that none of our current device implementations support this, although I already added the 'alpha' flag in device creation for this purpose.
If you can provide some code how to get a transparent background in an iPhone app I could add this to the current device code.

[prchakal]

Hi,

I have the same problem

My all code:

Code: Select all

 
- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
}
 
- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
 
- (IBAction)onStartClick:(id)sender
{
    ImageTargetsViewController *vc = [[ImageTargetsViewController alloc] init];
    [self presentViewController:vc animated:YES completion:nil];
}
 
-(void) viewWillAppear:(BOOL)a_animated
{
    [super viewWillAppear:a_animated];
    
    void *viewPtr = (__bridge_retained void*)(self.containerView);
    [self.containerView setBackgroundColor:[UIColor clearColor]];
    
    SIrrlichtCreationParameters params;
    params.DriverType = video::EDT_OGLES1;
    params.WindowSize = core::dimension2d<u32>(self.containerView.frame.size.width, self.containerView.frame.size.height);
    params.WindowId   = viewPtr;
    params.Bits       = 32;
    m_pDevice = createDeviceEx( (const SIrrlichtCreationParameters)params ) ;
    if( ! m_pDevice ) return ;
    
    NSString* oBunPath = [ [NSBundle mainBundle] bundlePath ] ;
    m_pDevice->getFileSystem()->changeWorkingDirectoryTo( [oBunPath cStringUsingEncoding:NSASCIIStringEncoding] ) ;
    
    IVideoDriver* driver = m_pDevice->getVideoDriver() ;
    ISceneManager* smgr = m_pDevice->getSceneManager() ;
    
    IAnimatedMesh* mesh = smgr->getMesh( "Assets/sydney.md2" ) ;
    if( ! mesh ) return ;
    
    IAnimatedMeshSceneNode* node = smgr->addAnimatedMeshSceneNode( mesh );
    if( node )
    {
        node->setMaterialFlag(EMF_LIGHTING, false);
        node->setMD2Animation(scene::EMAT_STAND);
        
        ITexture* pTex = driver->getTexture( "Assets/sydney.png" );
        node->setMaterialTexture( 0, pTex );
    }
    smgr->addCameraSceneNode( 0, vector3df(0,30,-100), vector3df(0,5,0) ) ;
    
    // iOS timer.
    m_oDispLnk = [ [UIScreen mainScreen] displayLinkWithTarget:self selector:@selector(updateDisplay) ] ;
    [ m_oDispLnk addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes ] ;
}
 
 
-(void) updateDisplay
{
    m_pDevice->run() ;
    
    m_pDevice->getVideoDriver()->beginScene( true, true, SColor(0,0,0,0) ) ;
    
    m_pDevice->getSceneManager()->drawAll() ;
    //m_pDevice->getGUIEnvironment()->drawAll() ;
    
    m_pDevice->getVideoDriver()->endScene();
}
 
 
-(void) viewDidDisappear:(BOOL)a_animated
{
    [super viewDidDisappear:a_animated];
    
    if( m_oDispLnk != nil )
        [ m_oDispLnk invalidate ] ;
    
    if( m_oDispLnk != NULL )
        m_pDevice->drop();
}
 

Obs 1: I tried use the color "255,0,0,0" and "0,0,0,0", but no success.
Obs 2: "self.containerView" is a view inside UIViewController->view. Because i will show behind a camera image and button. So i need a view for the irrlicht be in front of button and camera image.

SEE THE RESULT:

[Nadro]

You can try this:

Code: Select all

viewPtr.opaque = NO;
viewPtr.backgroundColor = [UIColor clearColor];

[prchakal]

Can anyone help us?

I have tried a new code, but no success:

Code: Select all

 
    self.containerView = [[UIView alloc] initWithFrame:self.view.frame];
    [self.view addSubview:self.containerView];
    
    self.containerView.backgroundColor = [UIColor clearColor];
    self.containerView.opaque = NO;
    self.containerView.clearsContextBeforeDrawing=YES;
    
    void *viewPtr = (__bridge_retained void*)(self.containerView);
    
    SIrrlichtCreationParameters params;
    params.DriverType = video::EDT_OGLES1;
    params.WindowSize = core::dimension2d<u32>(self.containerView.frame.size.width, self.containerView.frame.size.height);
    params.WindowId   = viewPtr;
    params.Bits       = 32;
 

[Nadro]

I can try to find a solution for this problem after sunday (+fix Irrlicht if bug related to this issue exist in an engine).