OpenGL antialiasing isn't working

I'm using the following code in order to antialias only the edges of my polygons:

glHint(GL_POLYGON_SMOOTH_HINT, GL_NICEST);
glEnable(GL_POLYGON_SMOOTH);

But it doesn't work.

I can force enable antialiasing by the nvidia control panel, and it does antialias my application polygons. With the code above, I even enabled blending, but it has no effect. Also the rendering code 开发者_Python百科shouldn't be changed since the nvidia control panel can turn it on, and it certainly cant modify my rendering code, it must be some on/off flag. What is it?

I've heard of "multisampling", but I don't need that.

Edit: the nvidia control panel setting is "application controlled" when it doesn't work.

You need to ask for a visual/pixelformat with support for multisampling. This is an attribute in the attribute list you pass to glXChooseFBConfig when using GLX/XLib, and wglChoosePixelformatARB when using the Win32 API. See my post here: Getting smooth, big points in OpenGL

It may be that your glEnable call is after the glHint call.

Try enabling blending

glBlendFunc(GL_SRC_ALPHA_SATURATE, GL_ONE);
glEnable(GL_BLEND);
glEnable(GL_POLYGON_SMOOTH);

Also following article might help

http://www.edm2.com/0603/opengl.html

Most likely, your hardware does not support it. Not all OpenGL implementations support antialiased polygons; see the OpenGL FAQ. I've definitely run into this problem before on a first-generation MacBook -- its GPU, the Intel GMA 950, does not support antialiased polygons.