Actually sorry, I take back what I said. It's been a while since I used GL. You can either have a vertex buffer for your quad:
GLfloat vertex_buffer[] = {
-1.0, -1.0, 0.0, /* bottom right triangle */
1.0, -1.0, 0.0,
1.0, 1.0, 0.0,
-1.0, -1.0, 0.0, /* top left triangle */
1.0, 1.0, 0.0,
-1.0, 1.0, 0.0
};
Or you can use an index buffer which saves some memory by re-using duplicate vertices:
GLfloat vertex_buffer[] = {
-1.0, -1.0, 0.0,
1.0, -1.0, 0.0,
-1.0, 1.0, 0.0,
1.0, 1.0, 0.0
};
GLint index_buffer[] = {
0, 1, 3, /* bottom right triangle */
0, 3, 2 /* top right triangle */
};
[EDIT] Or what James H said.
"Windows 10 doesn't only include spyware, it is
designed as spyware" --
Gaius Publius, The Big Picture RT Interview
"[...] we will access, disclose and
preserve personal data, including your content (such as the content of your emails, other
private communications or files in
private folders), when we have a good faith belief that doing so is necessary" --
Windows 10 Privacy Statement