how to bind a bitmap to texture in QT?

[saman_artorious]

As far as it is relevant to the current problem:

I want to get RGB values from a 24 bit BGR data. This data is from a raw image without a header.
I don't know how to convert the index of the buffer to its corresponding RGB values.
here is what I have done:

window_width  = 800;
 
    window_height = 600;
 
    size = window_width * window_height;
 
    pixels = new float[size*3];
 
    for(int i = 0, j = 0; i < size*3, j < size; i += 3, j++)
    {
        pixels[i+2] = bytes[i];
    }
 
    updateGL();

window_width  = 800;

    window_height = 600;

    size = window_width * window_height;

    pixels = new float[size*3];

    for(int i = 0, j = 0; i < size*3, j < size; i += 3, j++)
    {
        pixels[i+2] = bytes[i];
    }

    updateGL();

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void GlWidget:aintGL()
{

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

glDrawPixels(window_width,window_height,GL_RGB,GL_ FLOAT,pixels);
}

what am i missing?

[stampede]

I want to get RGB values from a 24 bit BGR data.

Are there alignment bytes added to BGR data ? Not relevant in case if width is a multiple of 4, but in general you can have each row size padded to multiple of 4 (in bytes). For example opencv does that (so size of 6x6 24 bit rgb image is not 108 but 120 bytes, additional 2 padding bytes for each row).
Ok sorry I'm probably confusing you, so the problem is this:

you have - [ B1,G1,R1, B2,G2,R2, ..., Bn,Gn,Rn ]
and you want - [ R1,G1,B1, R2,G2,B2, ..., Rn,Gn,Bn ]
?
You can do that conversion in-place, if you have buffered the data from the socket, you can change it without need of another buffer.
As you can see, you can leave the middle byte in each pixel alone, so you can do a simle swap (in case of in-place conversion), or three assignments (in case of copying). No need to have two loop variables btw., you can do that in single pass. This is three-four lines of code but i won't write it. Get a piece of paper and try to first perform this algorithm manually, its not that hard.

[saman_artorious]

Stampede you do not understand what the problem is. I know how to do a simple swap of these bits.
The packet size of raw data sent by server is of size 800*600 (size) only. Because the server gets the indices of RGB values. So, your equality is not correct. What I need to do logically, is to store the received packet in a packet of size size * 3 and assign values to it! but assign values to what? R? G? B? I have no idea because the received packet only contains indices of these RGB values. the below function only gave me some mixed colors:

void GlWidget::func(QByteArray btmp)
    {
        bytes.clear();
 
        bytes.resize(size*3*sizeof(unsigned char));
 
        for(int i = 0, j = 0; i < size*3, j < size; i += 3, j++)
        {
            bytes[i+2] = btmp[i];
        }
 
        updateGL();
    }
void GlWidget::paintGL()
{
 
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glDrawPixels(window_width,window_height,GL_BGR,GL_UNSIGNED_BYTE,bytes.constData());
}

void GlWidget::func(QByteArray btmp)
    {
        bytes.clear();

        bytes.resize(size*3*sizeof(unsigned char));

        for(int i = 0, j = 0; i < size*3, j < size; i += 3, j++)
        {
            bytes[i+2] = btmp[i];
        }

        updateGL();
    }
void GlWidget::paintGL()
{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glDrawPixels(window_width,window_height,GL_BGR,GL_UNSIGNED_BYTE,bytes.constData());
}

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[stampede]

received packet only contains indices of these RGB values

so you have indices but don't have a color table ? that's nice, to be honest I don't know what you should do in that case apart from asking the creators of server side to give you the color tables they use