uniform float time; /* in milliseconds */

void main()
{
    float s;
    vec4 t = gl_Vertex;
    t.y = 0.1*sin(0.001*time+5.0*gl_Vertex.x)*sin(0.001*time+5.0*gl_Vertex.z);
    gl_Position = gl_ModelViewProjectionMatrix * t;
    gl_FrontColor = gl_Color;
}