I'm trying to render two triangles that will fill the whole window and I have simple pass trough vertex shader:

#version 140

in vec4 vVertex;

void main()
{
gl_Position = vVertex;
}

Then I have the triangles in normalized device coordinates and after first creating the window everything is ok but when I use glViewport in processing of WM_SIZE it doesn't have any effect...I mean the triangles stay in same size??

I'm using GLEW 1.10.0 as static library and I have opengl32.lib for WGL stuff.