/*
*   Simple vertex shader to animate the position of grass / foliage
*       based on its location in the X-Z plane as well as a factor
*       of time. Passes texture coordinates and lighting information along.
*
*   Alexandri Zavodny, Fall 2010 
*       for CSE 40166/60166 Computer Graphics, University of Notre Dame
*/


uniform float time;
varying vec3 dirToLight, theNormal;

void main()
{
    theNormal = normalize(gl_NormalMatrix * gl_Normal);
    dirToLight = normalize(vec3(gl_LightSource[0].position - gl_ModelViewMatrix * gl_Vertex));

    gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;



    vec4 newVertex = gl_Vertex + vec4(sin(time+gl_Vertex.x)*gl_Vertex.y*0.5, 0, 0, 0.0);
    gl_Position = gl_ModelViewProjectionMatrix * newVertex;
}