I have a code for SSAO at: https://github.com/sjhalayka/opengl4_stlview​​

I have a different code for shadow mapping and SSAO at the same time: https://github.com/sjhalayka/opengl4_stlview_shadow_map​

Regarding the first code, included here is an image of what the 2nd colour attachment looks like. It's basically a normal + depth texture:

In the second code however, it's like the 2nd colour attachment is not being written to properly – it's like it's being overwritten with a duplicate of the values of the 1st colour attachment.

Any ideas why my 2nd colour attachment is not working?

The code for saving a colour attachment to disk is:

vector<unsigned char> output_pixels(2048*2048*4);

glReadBuffer(GL_COLOR_ATTACHMENT1);
glReadPixels(0, 0, 2048, 2048, GL_RGBA, GL_UNSIGNED_BYTE, &output_pixels[0]);


// Set up Targa TGA image data.
unsigned char  idlength = 0;
unsigned char  colourmaptype = 0;
unsigned char  datatypecode = 2;
unsigned short int colourmaporigin = 0;
unsigned short int colourmaplength = 0;
unsigned char  colourmapdepth = 0;
unsigned short int x_origin = 0;
unsigned short int y_origin = 0;

unsigned short int px = 2048;
unsigned short int py = 2048;
unsigned char  bitsperpixel = 32;
unsigned char  imagedescriptor = 0;
vector<char> idstring;



// Write Targa TGA file to disk.
ofstream out("attachment.tga", ios::binary);

if (!out.is_open())
{
	cout << "Failed to open TGA file for writing: attachment.tga" << endl;
	return;
}

out.write(reinterpret_cast<char*>(&idlength), 1);
out.write(reinterpret_cast<char*>(&colourmaptype), 1);
out.write(reinterpret_cast<char*>(&datatypecode), 1);
out.write(reinterpret_cast<char*>(&colourmaporigin), 2);
out.write(reinterpret_cast<char*>(&colourmaplength), 2);
out.write(reinterpret_cast<char*>(&colourmapdepth), 1);
out.write(reinterpret_cast<char*>(&x_origin), 2);
out.write(reinterpret_cast<char*>(&y_origin), 2);
out.write(reinterpret_cast<char*>(&px), 2);
out.write(reinterpret_cast<char*>(&py), 2);
out.write(reinterpret_cast<char*>(&bitsperpixel), 1);
out.write(reinterpret_cast<char*>(&imagedescriptor), 1);

out.write(reinterpret_cast<char*>(&output_pixels[0]), 2048*2048 * 4 * sizeof(unsigned char));

out.close();

exit(1);

After tinkering with this and that, I finally got it to work. Except… it only draws the first frame properly. Any idea why that would happen?

@taby OpenGL has global states, did you separate “create/init opengl” and “draw frame” code ?

I think you have problem in OpenGL states