[Qt-interest] Problem in creating empty QGLFrameBufferObject

[Samuel Rødal]

trinathpujari wrote:
> I want to use QGLFrameBufferObject for writing texts into
> another LCD device.
> But when i am creating by entering the below
>  
>              makeCurrent();
>              fbo = new QGLFramebufferObject(100, 100);
>  
> and when i run the program some data from previous example
> program is seen.
> Can anybody tell how to create a empty QGLFramebufferObject so i
> can use it for the second LCD device.
>  
> The example which i am trying, i am attaching here please
> confirm if it is correct way of creating the object.
>  
>           makeCurrent();
>           fbo = new QGLFramebufferObject(100, 100);
>           setWindowTitle(tr("OpenGL framebuffers 99999999999"));
>           fbo->bind();
>           fbo->drawTexture(QRectF(25,25,25,25),222,GL_TEXTURE_2D);
>           QPainter paint(fbo);
>           paint.fillRect(25,25,25,25,QColor(Qt::red));
>           fbo->release();
> 
>  Thanks in Advance.....
> 
> 
> 
> Regards
> 
> Trinath

Newly allocated OpenGL textures will typically contain random 
uninitialized data. To clear it you could do glClearColor(0, 0, 0, 0); 
glClear(GL_COLOR_BUFFER_BIT); after binding the fbo.

--
Samuel