glfwOpenWindow and glReadPixels modes ?

Question

Suppose I open a glfw window with:

glfwOpenWindow(width, height, 8,8,8,8,8,8, GLFW_WINDOW);

Then, I try to read it back with:

glReadPixels(0, 0, width, height, ..1.., ..2..);

I'm not sure what I should be putting in as ..1.. and ..2.. ; I think ..1.. should be GL_RGBA, but no idea for ..2..

Thanks!

Answer 1

Don't know if it helps, but I've found this article on GPWiki about glfwOpenWindow and the openGL docs for glReadPixels.

I've played with openGL a bit, but I haven't used these functions. Could you try something basic like:

glfwOpenWindow(width, height, 8,8,8,0,0,0, GLFW_WINDOW);

and

glReadPixels(0, 0, width, height, GL_RGB, GL_FLOAT);

And see if you get the right result or anything close, then incrementally add the details you need, like testing:

glfwOpenWindow(width, height, 8,8,8,8,0,0, GLFW_WINDOW);

then

glReadPixels(0, 0, width, height, GL_RGBA, GL_FLOAT);

and so on.